pentobarbital (Rx)

Hypnotic

Initial: 100 mg IV OR 150-200 mg IM

May give small increments of drug after at least 1 minute to reach full effect

Not to exceed 500 mg

Barbiturate Coma

Load: 10-15 mg/kg IV over 30 min; follow by 5 mg/kg IV q1hr for 3 doses  

Maintenance: 1 mg/kg/hr IV; may increase to 2-4 mg/kg/hr

Renal Failure

Use lower dose

Hepatic Failure

Use lower dose

Other Indications & Uses

Acute convulsive episodes

Hypnotic

2-6 mg/kg IM once; not to exceed 100 mg  

Pre-procedure Sedation

2-6 mg/kg IM, OR  

1-3 mg/kg IV

Not to exceed 100 mg IM

Not recommended; use lower dose if use becomes necessary

Contraindicated (21)

• cariprazine

  pentobarbital will decrease the level or effect of cariprazine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated. CYP3A4 is responsible for the formation and elimination of cariprazine's active metabolites. The effect of CYP3A4 inducers on cariprazine exposure has not been evaluated and the net effect is unclear.

• cobimetinib

  pentobarbital will decrease the level or effect of cobimetinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated. Avoid coadministration. Strong or moderate CYP3A inducers may decrease cobimetinib systemic exposure by >80% and reduce its efficacy.

• dienogest/estradiol valerate

  pentobarbital will decrease the level or effect of dienogest/estradiol valerate by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated. Women should not choose estradiol valerate/dienogest as their contraceptive while using strong CYP3A4 inducers due to potential decrease in contraceptive efficacy. Estradiol valerate/dienogest should not be used for at least 28 days after discontinuation of the inducer due to possibility of decreased contraceptive efficacy.

• doravirine

  pentobarbital will decrease the level or effect of doravirine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated. Coadministration of doravirine with a strong CYP3A inducer may decrease doravirine plasma concentrations and/or effects. Potential for loss of virologic response and possible resistance to doravirine.

• elbasvir/grazoprevir

  pentobarbital will decrease the level or effect of elbasvir/grazoprevir by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated. The therapeutic effect of elbasvir/grazoprevir may be reduced if coadministered with strong CYP3A inducers and is therefore contraindicated.

• elvitegravir/cobicistat/emtricitabine/tenofovir DF

  pentobarbital decreases levels of elvitegravir/cobicistat/emtricitabine/tenofovir DF by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated. May lead to loss of virologic response and possible resistance.

• fostemsavir

  pentobarbital will decrease the level or effect of fostemsavir by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated. Coadministration of fostemsavir (prodrug) with strong CYP3A4 inducers significantly decreases temsavir (active moiety) plasma concentrations, which may lead to loss of virologic response and resistance.

• isavuconazonium sulfate

  pentobarbital will decrease the level or effect of isavuconazonium sulfate by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated.

• lonafarnib

  pentobarbital will decrease the level or effect of lonafarnib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated. Lonafarnib is a sensitive CYP3A4 substrate. Coadministration with strong or moderate CYP3A4 inducers is contraindicated.

• lorlatinib

  pentobarbital will decrease the level or effect of lorlatinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated. Coadministration of lorlatinib with strong CYP3A inducers is contraindicated. Discontinue the strong CYP3A inducer for 3 plasma half-lives before initiating lorlatinib.

• lumacaftor/ivacaftor

  pentobarbital will decrease the level or effect of lumacaftor/ivacaftor by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated. Strong CYP3A inducers have minimal effect on lumacaftor exposure, but decreased ivacaftor exposure (AUC) by 57%. This may reduce the effectiveness of lumacaftor/ivacaftor. Therefore, coadministration is not recommended.

• lumefantrine

  pentobarbital will decrease the level or effect of lumefantrine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated. Coadministration with strong CYP3A4 inducers can result in decreased serum concentrations and loss of antimalarial efficacy

• lurasidone

  pentobarbital decreases levels of lurasidone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated. Contraindicated.

• mavacamten

  pentobarbital will decrease the level or effect of mavacamten by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated.

• naloxegol

  pentobarbital will decrease the level or effect of naloxegol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated. Use of naloxegol with strong CYP3A4 inducers is not recommended

• ombitasvir/paritaprevir/ritonavir & dasabuvir (DSC)

  pentobarbital will decrease the level or effect of ombitasvir/paritaprevir/ritonavir & dasabuvir (DSC) by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated. Strong CYP3A4 inducers may reduce partiaprevir and ritonavir levels, and therefore decreased efficacy of Viekira Pak

• panobinostat

  pentobarbital decreases levels of panobinostat by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated. Strong CYP3A4 inducers can reduce panobinostat levels by ~70% and lead to treatment failure.

• praziquantel

  pentobarbital decreases levels of praziquantel by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated. Strong CYP450 inducers significantly decrease praziquantel blood levels.

• regorafenib

  pentobarbital, regorafenib. affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated. Strong CYP3A4 inducers decrease regorafenib levels and increase exposure of the active metabolite M-5.

• roflumilast

  pentobarbital will decrease the level or effect of roflumilast by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated. Coadministration not recommended; strong cytochrome P450 enzyme inducers decrease systemic exposure to roflumilast and may reduce the therapeutic effectiveness

• vandetanib

  pentobarbital decreases levels of vandetanib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated. Avoid coadministration with potent CYP3A4 inducers; these drugs reduce exposure to vandetanib by up to 40%.

Serious - Use Alternative (134)

• abemaciclib

  pentobarbital will decrease the level or effect of abemaciclib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Coadministration of abemaciclib with strong CYP3A4 inducers reduces plasma concentration of abemaciclib and its metabolites.

• alosetron

  pentobarbital will decrease the level or effect of alosetron by affecting hepatic enzyme CYP1A2 metabolism. Avoid or Use Alternate Drug.

• alpelisib

  pentobarbital will decrease the level or effect of alpelisib by pharmacodynamic synergism. Avoid or Use Alternate Drug. Avoid coadministration of alpelisib (CYP3A4 substrate) with strong CYP3A4 inducers.

• antithrombin alfa

  pentobarbital decreases effects of antithrombin alfa by increasing metabolism. Avoid or Use Alternate Drug.

• antithrombin III

  pentobarbital decreases effects of antithrombin III by increasing metabolism. Avoid or Use Alternate Drug.

• apremilast

  pentobarbital will decrease the level or effect of apremilast by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Coadministration with strong CYP inducers results in a significant decrease of systemic exposure of apremilast, which may result in loss of efficacy

• argatroban

  pentobarbital decreases effects of argatroban by increasing metabolism. Avoid or Use Alternate Drug.

• artemether/lumefantrine

  pentobarbital will decrease the level or effect of artemether/lumefantrine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Coadministration with strong CYP3A4 inducers can result in decreased serum concentrations and loss of antimalarial efficacy

• avapritinib

  pentobarbital will decrease the level or effect of avapritinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• axitinib

  pentobarbital decreases levels of axitinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Selection of concomitant medication with no or minimal CYP3A4 induction potential is recommended.

• bedaquiline

  pentobarbital will decrease the level or effect of bedaquiline by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of bedaquiline with strong CYP3A4 inducers due to potential for decreased therapeutic effect

• bemiparin

  pentobarbital decreases effects of bemiparin by increasing metabolism. Avoid or Use Alternate Drug.

• benzhydrocodone/acetaminophen

  benzhydrocodone/acetaminophen, pentobarbital. Either increases toxicity of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Profound sedation, respiratory depression, coma, and death may result if coadministered. Reserve concomitant prescribing of these drugs in patients for whom other treatment options are inadequate. Limit dosages and durations to the minimum required. Monitor closely for signs of respiratory depression and sedation.
  
  benzhydrocodone/acetaminophen and pentobarbital both increase sedation. Avoid or Use Alternate Drug. Limit use to patients for whom alternative treatment options are inadequate

• bivalirudin

  pentobarbital decreases effects of bivalirudin by increasing metabolism. Avoid or Use Alternate Drug.

• bosutinib

  pentobarbital decreases levels of bosutinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Strong CYP3A4 inducers decreased bosutinib plasma concentration by ~85%.

• brigatinib

  pentobarbital will decrease the level or effect of brigatinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Coadministration with strong CYP3A4 inducers may decrease brigatinib efficacy.

• buprenorphine subdermal implant

  buprenorphine subdermal implant and pentobarbital both increase sedation. Avoid or Use Alternate Drug. Limit use to patients for whom alternative treatment options are inadequate

• buprenorphine transdermal

  buprenorphine transdermal and pentobarbital both increase sedation. Avoid or Use Alternate Drug. Limit use to patients for whom alternative treatment options are inadequate

• cabozantinib

  pentobarbital will decrease the level or effect of cabozantinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of cabozantinib with strong CYP3A4 inducers. If a strong CYP3A4 inducer is required, increase cabozantinib dose by 40 mg/day (Cometriq) or by 20 mg/day (Cabometyx). Resume previous dose 2-3 days after strong CYP3A4 inducer discontinued.

• calcium/magnesium/potassium/sodium oxybates

  pentobarbital, calcium/magnesium/potassium/sodium oxybates. Either increases effects of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Profound sedation, respiratory depression, coma, and death may result if coadministered. Reserve concomitant prescribing of these drugs in patients for whom other treatment options are inadequate. Limit dosages and durations to the minimum required. Monitor closely for signs of respiratory depression and sedation.

• ceritinib

  pentobarbital decreases levels of ceritinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• copanlisib

  pentobarbital will decrease the level or effect of copanlisib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of copanlisib with strong CYP3A4 inducers.

• dabrafenib

  pentobarbital decreases levels of dabrafenib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• dalteparin

  pentobarbital decreases effects of dalteparin by increasing metabolism. Avoid or Use Alternate Drug.

• daridorexant

  pentobarbital will decrease the level or effect of daridorexant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• deflazacort

  pentobarbital will decrease the level or effect of deflazacort by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of deflazacort with moderate or strong CYP3A4 inducers.

• dihydroergotamine

  pentobarbital will decrease the level or effect of dihydroergotamine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• dihydroergotamine intranasal

  pentobarbital will decrease the level or effect of dihydroergotamine intranasal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• dronedarone

  pentobarbital will decrease the level or effect of dronedarone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• duloxetine

  pentobarbital will decrease the level or effect of duloxetine by affecting hepatic enzyme CYP1A2 metabolism. Avoid or Use Alternate Drug.

• duvelisib

  pentobarbital will decrease the level or effect of duvelisib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Coadministration with a strong CYP3A inducer decreases duvelisib area under the curve (AUC), which may reduce duvelisib efficacy.

• elacestrant

  pentobarbital will decrease the level or effect of elacestrant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• eliglustat

  pentobarbital will decrease the level or effect of eliglustat by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Strong CYP3A inducers significantly decreases eliglustat exposure; coadministration not recommended

• elvitegravir

  pentobarbital will decrease the level or effect of elvitegravir by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid; coadministration with CYP3A inducers may result in decreased plasma concentrations of elvitegravir and/or a concomitantly administered protease inhibitor and lead to loss of therapeutic effect and to possible resistance

• enoxaparin

  pentobarbital decreases effects of enoxaparin by increasing metabolism. Avoid or Use Alternate Drug.

• erdafitinib

  pentobarbital will decrease the level or effect of erdafitinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• ergotamine

  pentobarbital will decrease the level or effect of ergotamine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• erythromycin base

  pentobarbital will decrease the level or effect of erythromycin base by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• erythromycin ethylsuccinate

  pentobarbital will decrease the level or effect of erythromycin ethylsuccinate by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• erythromycin lactobionate

  pentobarbital will decrease the level or effect of erythromycin lactobionate by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• erythromycin stearate

  pentobarbital will decrease the level or effect of erythromycin stearate by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• ethinylestradiol

  pentobarbital will decrease the level or effect of ethinylestradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. The efficacy of hormonal contraceptives may be reduced. Use of a nonhormonal contraceptive is recommended.

• everolimus

  pentobarbital will decrease the level or effect of everolimus by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• fedratinib

  pentobarbital will decrease the level or effect of fedratinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Effect of coadministering a strong CYP3A4 inducer with fedratinib has not been studied.

• fentanyl

  fentanyl, pentobarbital. Either increases effects of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Coadministration with other CNS depressants, such as skeletal muscle relaxants, may cause respiratory depression, hypotension, profound sedation, coma, and/or death. Consider dose reduction of either or both agents to avoid serious adverse effects. Monitor for hypotension, respiratory depression, and profound sedation.

• fentanyl intranasal

  fentanyl intranasal, pentobarbital. Either increases effects of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Coadministration with other CNS depressants, such as skeletal muscle relaxants, may cause respiratory depression, hypotension, profound sedation, coma, and/or death. Consider dose reduction of either or both agents to avoid serious adverse effects. Monitor for hypotension, respiratory depression, and profound sedation.

• fentanyl transdermal

  fentanyl transdermal, pentobarbital. Either increases effects of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Coadministration with other CNS depressants, such as skeletal muscle relaxants, may cause respiratory depression, hypotension, profound sedation, coma, and/or death. Consider dose reduction of either or both agents to avoid serious adverse effects. Monitor for hypotension, respiratory depression, and profound sedation.

• fentanyl transmucosal

  fentanyl transmucosal, pentobarbital. Either increases effects of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Coadministration with other CNS depressants, such as skeletal muscle relaxants, may cause respiratory depression, hypotension, profound sedation, coma, and/or death. Consider dose reduction of either or both agents to avoid serious adverse effects. Monitor for hypotension, respiratory depression, and profound sedation.

• fexinidazole

  pentobarbital will increase the level or effect of fexinidazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. CYP450 inducers may significantly increase plasma concentrations of fexinidazole?s active metabolites: fexinidazole sulfoxide (M1) and fexinidazole sulfone (M2). M2 plasma concentrations associated with increased QT prolongation risks.

• finerenone

  pentobarbital will decrease the level or effect of finerenone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• fondaparinux

  pentobarbital decreases effects of fondaparinux by increasing metabolism. Avoid or Use Alternate Drug.

• fostamatinib

  pentobarbital will decrease the level or effect of fostamatinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• ganaxolone

  pentobarbital will decrease the level or effect of ganaxolone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of ganaxolone with moderate or strong CYP3A4 inducers. If coadministration unavoidable, consider increasing ganaxolone dose; however, do not exceed maximum daily dose for weight.

• glasdegib

  pentobarbital will decrease the level or effect of glasdegib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of glasdegib with strong CYP3A inducers.

• heparin

  pentobarbital decreases effects of heparin by increasing metabolism. Avoid or Use Alternate Drug.

• hydrocodone

  hydrocodone, pentobarbital. Either increases toxicity of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Profound sedation, respiratory depression, coma, and death may result if coadministered. Reserve concomitant prescribing of these drugs in patients for whom other treatment options are inadequate. Limit dosages and durations to the minimum required. Monitor closely for signs of respiratory depression and sedation.

• ibrutinib

  pentobarbital decreases levels of ibrutinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Strong CYP3A inducers decrease ibrutinib plasma concentrations by ~10-fold.

• idelalisib

  pentobarbital will decrease the level or effect of idelalisib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration; strong CYP3A4 inducers significantly decrease idelalisib systemic exposure

• infigratinib

  pentobarbital will decrease the level or effect of infigratinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• isocarboxazid

  isocarboxazid, pentobarbital. Other (see comment). Contraindicated. Comment: CNS depressants such as barbiturates should not be used in combination with isocarboxazid.

• istradefylline

  pentobarbital will decrease the level or effect of istradefylline by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of istradefylline with strong CYP3A4 inducers.

• ivabradine

  pentobarbital will decrease the level or effect of ivabradine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of ivabradine with moderate CYP3A4 inducers.

• ivacaftor

  pentobarbital decreases levels of ivacaftor by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration with strong CYP3A4 inducers; systemic exposure of ivacaftor substantially reduced (ie, ~9-fold).

• ivosidenib

  pentobarbital will increase the level or effect of ivosidenib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Coadministration of ivosidenib with strong CYP3A4 inducers decreased ivosidenib plasma concentrations.

• ixazomib

  pentobarbital will decrease the level or effect of ixazomib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of ixazomib with strong CYP3A inducers. Strong inducers have been shown to decrease ixazomib Cmax by 54% and AUC by 74%.

• larotrectinib

  pentobarbital will decrease the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of larotrectinib with strong CYP3A4 inducers is unavoidable, double larotrectinib dose. Resume prior larotrectinib dose once CYP3A4 inducer discontinued for 3-5 half-lives

• lefamulin

  pentobarbital will decrease the level or effect of lefamulin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of lefamulin with strong or moderate CYP3A inducers unless the benefit outweighs risks. Monitor for reduced efficacy.

• lemborexant

  pentobarbital will decrease the level or effect of lemborexant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.
  
  lemborexant, pentobarbital. Either increases effects of the other by sedation. Avoid or Use Alternate Drug. Use of lemborexant with other drugs to treat insomnia is not recommended.

• lenacapavir

  pentobarbital will decrease the level or effect of lenacapavir by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of lenacapavir with moderate CYP3A4 inducers.

• leniolisib

  pentobarbital will decrease the level or effect of leniolisib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• lovastatin

  pentobarbital will decrease the level or effect of lovastatin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• lumateperone

  pentobarbital will decrease the level or effect of lumateperone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• lurbinectedin

  pentobarbital will decrease the level or effect of lurbinectedin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• macimorelin

  pentobarbital will decrease the level or effect of macimorelin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Potential for false positive test results if macimorelin and strong CYP3A4 inducers are coadministered. Discontinue strong CYP3A4 inducer, allowing for sufficient washout time, before testing.

• macitentan

  pentobarbital will decrease the level or effect of macitentan by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministering macitentan with strong CYP3A4 inducers

• mestranol

  pentobarbital decreases levels of mestranol by increasing metabolism. Avoid or Use Alternate Drug. May result in contraceptive failure.

• methoxyflurane

  pentobarbital increases toxicity of methoxyflurane by increasing metabolism. Contraindicated. Increased metabolism of methoxyflurane to nephrotoxic compounds.

• metoclopramide intranasal

  pentobarbital, metoclopramide intranasal. Either increases effects of the other by Other (see comment). Avoid or Use Alternate Drug. Comment: Avoid use of metoclopramide intranasal or interacting drug, depending on importance of drug to patient.

• midostaurin

  pentobarbital will decrease the level or effect of midostaurin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Strong CYP3A4 inducers may decrease midostaurin concentrations resulting in reduced efficacy.

• mobocertinib

  pentobarbital will decrease the level or effect of mobocertinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• naldemedine

  pentobarbital will decrease the level or effect of naldemedine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration with strong CYP3A4 inducers.

• neratinib

  pentobarbital will decrease the level or effect of neratinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of neratinib with strong/moderate CYP3A4 inducers.

• netupitant/palonosetron

  pentobarbital will decrease the level or effect of netupitant/palonosetron by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Netupitant is mainly metabolized by CYP3A4; avoid use in patients who are chronically using a strong CYP3A4 inducer

• olaparib

  pentobarbital will decrease the level or effect of olaparib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of olaparib with strong CYP3A4 inducers.

• olopatadine intranasal

  pentobarbital and olopatadine intranasal both increase sedation. Avoid or Use Alternate Drug. Coadministration increases risk of CNS depression, which can lead to additive impairment of psychomotor performance and cause daytime impairment.

• olutasidenib

  pentobarbital will decrease the level or effect of olutasidenib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Strong or moderate CYP3A inducers decrease olutasidenib (a CYP3A4 substrate) plasma concentrations and efficacy.

• omaveloxolone

  pentobarbital will decrease the level or effect of omaveloxolone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• osimertinib

  pentobarbital will decrease the level or effect of osimertinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid concomitant use of osimertinib with strong CYP3A inducers.

• pacritinib

  pentobarbital will decrease the level or effect of pacritinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• palbociclib

  pentobarbital will decrease the level or effect of palbociclib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Strong CYP3A inducers decrease palbociclib plasma exposure by ~85%.

• pemigatinib

  pentobarbital will decrease the level or effect of pemigatinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• pexidartinib

  pentobarbital will decrease the level or effect of pexidartinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• phenindione

  pentobarbital decreases effects of phenindione by increasing metabolism. Avoid or Use Alternate Drug.

• pomalidomide

  pentobarbital decreases levels of pomalidomide by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• ponatinib

  pentobarbital decreases levels of ponatinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid unless the coadministration outweighs the possible risk of ponatinib underexposure; monitor for signs of reduced efficacy.

• pralsetinib

  pentobarbital will decrease the level or effect of pralsetinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If unable to avoid, double current pralsetinib dose starting on Day 7 of coadministration with strong CYP3A inducer. After inducer has been discontinued for at least 14 days, resume previous pralsetinib dose.

• pretomanid

  pentobarbital will decrease the level or effect of pretomanid by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Pretomanid is a CYP3A4 substrate. Avoid coadministration of strong or moderate CYP3A4. inducers

• protamine

  pentobarbital decreases effects of protamine by increasing metabolism. Avoid or Use Alternate Drug.

• ranolazine

  pentobarbital will decrease the level or effect of ranolazine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• rimegepant

  pentobarbital will decrease the level or effect of rimegepant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• ripretinib

  pentobarbital will decrease the level or effect of ripretinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Coadministration with a strong CYP3A inhibitor will decrease systemic exposure to ripretinib and its active metabolite (DP-5439), which may decrease risk of adverse reactions.

• rolapitant

  pentobarbital will decrease the level or effect of rolapitant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Long-term coadministration of strong CYP3A4 inducers with rolapitant may significantly decrease rolapitant efficacy.

• romidepsin

  pentobarbital will decrease the level or effect of romidepsin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• selinexor

  selinexor, pentobarbital. unspecified interaction mechanism. Avoid or Use Alternate Drug. Patients treated with selinexor may experience neurological toxicities. Avoid taking selinexor with other medications that may cause dizziness or confusion.

• selumetinib

  pentobarbital will decrease the level or effect of selumetinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• sildenafil

  pentobarbital will decrease the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Potent CYP3A4 inducers are expected to cause substantial decreases in sildenafil plasma levels

• silodosin

  pentobarbital will decrease the level or effect of silodosin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• simvastatin

  pentobarbital will decrease the level or effect of simvastatin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• siponimod

  pentobarbital will decrease the level or effect of siponimod by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Coadministration of siponimod with a drug that causes moderate CYP2C9 plus a moderate or strong CYP3A4 inducer is not recommended. Coadministration with moderate or strong CYP3A4 inducers alone is not recommended for patients with CYP2C9*1/*3 and*2/*3 genotype.

• sirolimus

  pentobarbital will decrease the level or effect of sirolimus by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• sodium oxybate

  pentobarbital, sodium oxybate. Either increases effects of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Profound sedation, respiratory depression, coma, and death may result if coadministered. Reserve concomitant prescribing of these drugs in patients for whom other treatment options are inadequate. Limit dosages and durations to the minimum required. Monitor closely for signs of respiratory depression and sedation.

• sofosbuvir/velpatasvir

  pentobarbital will decrease the level or effect of sofosbuvir/velpatasvir by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Velpatasvir is a substrate of CYP2B6, CYP2C8, and CYP3A4. Drugs that are moderate-to-potent inducers of CYP2B6, CYP2C8, or CYP3A4 may significantly decrease velpatasvir plasma concentrations, leading to potentially reduced therapeutic effect.

• sonidegib

  pentobarbital will decrease the level or effect of sonidegib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of sonidegib with strong or moderate CYP3A4 inducers.

• sotorasib

  pentobarbital will decrease the level or effect of sotorasib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• stiripentol

  pentobarbital will decrease the level or effect of stiripentol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If unable to avoid coadministration of stiripentol with strong CYP3A4 inducers, increase stiripentol dose.

• sufentanil SL

  sufentanil SL, pentobarbital. Either increases toxicity of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Coadministration may result in hypotension, profound sedation, respiratory depression, coma, and death. Reserve concomitant prescribing of these drugs in patients for whom other treatment options are inadequate. Limit dosages and durations to the minimum required. Monitor closely for signs of respiratory depression and sedation.

• tazemetostat

  pentobarbital will decrease the level or effect of tazemetostat by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• tezacaftor

  pentobarbital will decrease the level or effect of tezacaftor by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• tivozanib

  pentobarbital will decrease the level or effect of tivozanib by affecting hepatic enzyme CYP2E1 metabolism. Avoid or Use Alternate Drug.

• tizanidine

  pentobarbital will decrease the level or effect of tizanidine by affecting hepatic enzyme CYP1A2 metabolism. Avoid or Use Alternate Drug.

• tolvaptan

  pentobarbital will decrease the level or effect of tolvaptan by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• trabectedin

  pentobarbital will decrease the level or effect of trabectedin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• tucatinib

  pentobarbital will decrease the level or effect of tucatinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• ubrogepant

  pentobarbital will decrease the level or effect of ubrogepant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• upadacitinib

  pentobarbital will decrease the level or effect of upadacitinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid upadacitinib coadministration with strong CYP3A4 inducers.

• valbenazine

  pentobarbital will increase the level or effect of valbenazine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Concomitant use not recommended.

• valerian

  valerian increases effects of pentobarbital by pharmacodynamic synergism. Avoid or Use Alternate Drug. May enhance CNS depression.
  
  valerian and pentobarbital both increase sedation. Avoid or Use Alternate Drug.

• venetoclax

  pentobarbital will decrease the level or effect of venetoclax by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of venetoclax with strong or moderate CYP3A inducers. Consider alternative treatment with agents that have less CYP3A induction.

• voclosporin

  pentobarbital will decrease the level or effect of voclosporin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• vonoprazan

  pentobarbital will decrease the level or effect of vonoprazan by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• vorapaxar

  pentobarbital decreases levels of vorapaxar by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• voriconazole

  pentobarbital decreases levels of voriconazole by increasing metabolism. Contraindicated.

• voxelotor

  pentobarbital will decrease the level or effect of voxelotor by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Voxelotor is primarily metabolized by CYP3A4. Avoid coadministration with moderate or strong CYP3A4 inducers. If unable to avoid coadministration, increase voxelotor dose (see Dosage Modifications).

• zanubrutinib

  pentobarbital will decrease the level or effect of zanubrutinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of zanubrutinib (a CYP3A4 substrate) with moderate CYP3A4 inhibitors. If unavoidable, increase zanubrutinib dose to 320 mg PO BID. After discontinuing the CYP3A4 inhibitor, resume previous dose of zanubrutinib.

Monitor Closely (362)

• abiraterone

  pentobarbital will decrease the level or effect of abiraterone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• acalabrutinib

  pentobarbital will decrease the level or effect of acalabrutinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• acebutolol

  pentobarbital decreases levels of acebutolol by increasing metabolism. Use Caution/Monitor. Consider a higher beta-blocker dose during coadministration of pentobarbital. Atenolol, sotalol, nadolol less likely to be affected than other beta blockers.

• acrivastine

  acrivastine and pentobarbital both increase sedation. Use Caution/Monitor.

• albuterol

  pentobarbital increases and albuterol decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• alfentanil

  pentobarbital and alfentanil both increase sedation. Use Caution/Monitor.

• almotriptan

  pentobarbital will decrease the level or effect of almotriptan by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• alprazolam

  pentobarbital will decrease the level or effect of alprazolam by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
  
  pentobarbital and alprazolam both increase sedation. Use Caution/Monitor.

• amifostine

  amifostine, pentobarbital. Either increases effects of the other by anti-hypertensive channel blocking. Use Caution/Monitor. Monitor hemodynamic changes, specifically for signs of hypotension, if using barbiturates with blood pressure lowering medications. .

• amiodarone

  pentobarbital will decrease the level or effect of amiodarone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• amisulpride

  amisulpride and pentobarbital both increase sedation. Use Caution/Monitor.

• amitriptyline

  pentobarbital will decrease the level or effect of amitriptyline by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.
  
  pentobarbital will decrease the level or effect of amitriptyline by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely.
  
  pentobarbital and amitriptyline both increase sedation. Use Caution/Monitor.

• amlodipine

  pentobarbital will decrease the level or effect of amlodipine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• amobarbital

  amobarbital and pentobarbital both increase sedation. Use Caution/Monitor.

• amoxapine

  pentobarbital and amoxapine both increase sedation. Use Caution/Monitor.

• apomorphine

  pentobarbital and apomorphine both increase sedation. Use Caution/Monitor.

• aprepitant

  pentobarbital will decrease the level or effect of aprepitant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• arformoterol

  pentobarbital increases and arformoterol decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• aripiprazole

  pentobarbital will decrease the level or effect of aripiprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
  
  pentobarbital and aripiprazole both increase sedation. Use Caution/Monitor.

• armodafinil

  pentobarbital increases and armodafinil decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• asenapine

  asenapine and pentobarbital both increase sedation. Use Caution/Monitor.

• asenapine transdermal

  asenapine transdermal and pentobarbital both increase sedation. Use Caution/Monitor.

• atenolol

  pentobarbital decreases levels of atenolol by increasing metabolism. Use Caution/Monitor. Consider a higher beta-blocker dose during coadministration of pentobarbital. Atenolol, sotalol, nadolol less likely to be affected than other beta blockers.

• atogepant

  pentobarbital will decrease the level or effect of atogepant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Recommended atogepant dosage with concomitant use of strong or moderate CYP3A4 inducers is 30 mg or 60 mg qDay.

• atorvastatin

  pentobarbital will decrease the level or effect of atorvastatin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• avanafil

  pentobarbital will decrease the level or effect of avanafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. For patients with ED, monitor response carefully because of potential for decreased effectiveness.

• avapritinib

  avapritinib and pentobarbital both increase sedation. Use Caution/Monitor.

• azelastine

  azelastine and pentobarbital both increase sedation. Use Caution/Monitor.

• baclofen

  pentobarbital and baclofen both increase sedation. Use Caution/Monitor.

• bazedoxifene/conjugated estrogens

  pentobarbital will decrease the level or effect of bazedoxifene/conjugated estrogens by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• belladonna and opium

  pentobarbital and belladonna and opium both increase sedation. Use Caution/Monitor.

• belumosudil

  pentobarbital will decrease the level or effect of belumosudil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Increase belumosudil dosage to 200 mg PO BID when coadministered with strong CYP3A inducers.

• benazepril

  pentobarbital, benazepril. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Enhanced hypotensive effects.

• bendamustine

  pentobarbital decreases levels of bendamustine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor. Concentrations of active metabolites may be increased.

• benperidol

  pentobarbital and benperidol both increase sedation. Use Caution/Monitor.

• benzhydrocodone/acetaminophen

  pentobarbital will decrease the level or effect of benzhydrocodone/acetaminophen by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Caution when discontinuing CYP3A4 inducers that are coadministered with benzhydrocodone (prodrug of hydrocodone); plasma concentrations of hydrocodone may increase and can result in potentially fatal respiratory depression.

• benzphetamine

  pentobarbital increases and benzphetamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• betaxolol

  pentobarbital decreases levels of betaxolol by increasing metabolism. Use Caution/Monitor. Consider a higher beta-blocker dose during coadministration of pentobarbital. Atenolol, sotalol, nadolol less likely to be affected than other beta blockers.

• bexarotene

  pentobarbital will decrease the level or effect of bexarotene by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• bisoprolol

  pentobarbital decreases levels of bisoprolol by increasing metabolism. Use Caution/Monitor. Consider a higher beta-blocker dose during coadministration of pentobarbital. Atenolol, sotalol, nadolol less likely to be affected than other beta blockers.

• bortezomib

  pentobarbital will decrease the level or effect of bortezomib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• brexanolone

  brexanolone, pentobarbital. Either increases toxicity of the other by sedation. Use Caution/Monitor.

• brexpiprazole

  pentobarbital will decrease the level or effect of brexpiprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Double brexpiprazole dose over 1-2 weeks if administered with a strong CYP3A4 inducer.
  
  brexpiprazole and pentobarbital both increase sedation. Use Caution/Monitor.

• brimonidine

  brimonidine and pentobarbital both increase sedation. Use Caution/Monitor.

• brivaracetam

  brivaracetam and pentobarbital both increase sedation. Use Caution/Monitor.

• brompheniramine

  brompheniramine and pentobarbital both increase sedation. Use Caution/Monitor.

• budesonide

  pentobarbital will decrease the level or effect of budesonide by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• bupivacaine implant

  pentobarbital, bupivacaine implant. Either increases toxicity of the other by Other (see comment). Use Caution/Monitor. Comment: Local anesthetics may increase the risk of developing methemoglobinemia when concurrently exposed to drugs that also cause methemoglobinemia.

• buprenorphine

  pentobarbital and buprenorphine both increase sedation. Use Caution/Monitor.
  
  pentobarbital will decrease the level or effect of buprenorphine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• buprenorphine buccal

  pentobarbital and buprenorphine buccal both increase sedation. Use Caution/Monitor.
  
  pentobarbital will decrease the level or effect of buprenorphine buccal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• buprenorphine subdermal implant

  pentobarbital will decrease the level or effect of buprenorphine subdermal implant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Monitor patients already on buprenorphine subdermal implant who require newly-initiated treatment with CYP3A4 inducer for signs and symptoms of withdrawal. If the dose of the concomitant CYP3A4 inducer cannot be reduced or discontinued, implant removal may be necessary and the patient should then be treated with a buprenorphine dosage form that permits dose adjustments. If a CYP3A4 inducer is discontinued in a patient who has been stabilized on buprenorphine, monitor the patient for overmedication.

• buprenorphine, long-acting injection

  pentobarbital will decrease the level or effect of buprenorphine, long-acting injection by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Patients who transfer to buprenorphine long-acting injection from transmucosal buprenorphine coadministered with CYP3A4 inducers should be monitored to ensure buprenorphine plasma levels are adequate. If the buprenorphine dose is inadequate and the CYP3A4 inducer cannot be reduced or discontinued, transition the patient back to a buprenorphine formulation that permits dose adjustments.
  
  pentobarbital increases toxicity of buprenorphine, long-acting injection by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of buprenorphine and benzodiazepines or other CNS depressants increases risk of adverse reactions including overdose, respiratory depression, and death. Cessation of benzodiazepines or other CNS depressants is preferred in most cases. In some cases, monitoring at a higher level of care for tapering CNS depressants may be appropriate. In others, gradually tapering a patient off of a prescribed benzodiazepine or other CNS depressant or decreasing to the lowest effective dose may be appropriate.

• bupropion

  pentobarbital, bupropion. increasing metabolism. Use Caution/Monitor. Decr levels of bupropion, but incr levels of active metabolites. .

• buspirone

  pentobarbital will decrease the level or effect of buspirone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• butabarbital

  butabarbital and pentobarbital both increase sedation. Use Caution/Monitor.

• butalbital

  butalbital and pentobarbital both increase sedation. Use Caution/Monitor.

• butorphanol

  pentobarbital and butorphanol both increase sedation. Use Caution/Monitor.

• cabazitaxel

  pentobarbital will decrease the level or effect of cabazitaxel by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Coadministration of strong CYP3A4 inducers may decrease cabazitaxel concentrations. Avoid coadministration.

• caffeine

  pentobarbital increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• calcifediol

  pentobarbital, calcifediol. affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Drugs that stimulate microsomal hydroxylation reduce the half-life of calcifediol.

• cannabidiol

  pentobarbital will decrease the level or effect of cannabidiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Consider an increase in cannabidiol dosage (based on clinical response and tolerability) when coadministered with a strong CYP3A4 inducer.

• captopril

  pentobarbital, captopril. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Both drugs lower blood pressure. Monitor blood pressure.

• carbamazepine

  pentobarbital will decrease the level or effect of carbamazepine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• carbinoxamine

  carbinoxamine and pentobarbital both increase sedation. Use Caution/Monitor.

• carisoprodol

  pentobarbital and carisoprodol both increase sedation. Use Caution/Monitor.

• carvedilol

  pentobarbital will decrease the level or effect of carvedilol by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.
  
  pentobarbital decreases levels of carvedilol by increasing metabolism. Use Caution/Monitor. Consider a higher beta-blocker dose during coadministration of pentobarbital. Atenolol, sotalol, nadolol less likely to be affected than other beta blockers.

• celiprolol

  pentobarbital decreases levels of celiprolol by increasing metabolism. Use Caution/Monitor. Atenolol, sotalol, nadolol less likely to be affected than other beta blockers.

• cenobamate

  cenobamate, pentobarbital. Either increases effects of the other by sedation. Use Caution/Monitor.

• chloral hydrate

  pentobarbital and chloral hydrate both increase sedation. Use Caution/Monitor.

• chloramphenicol

  chloramphenicol increases levels of pentobarbital by decreasing metabolism. Use Caution/Monitor.

• chlordiazepoxide

  pentobarbital and chlordiazepoxide both increase sedation. Use Caution/Monitor.

• chlorpheniramine

  chlorpheniramine and pentobarbital both increase sedation. Use Caution/Monitor.

• chlorpromazine

  pentobarbital and chlorpromazine both increase sedation. Use Caution/Monitor.

• chlorzoxazone

  pentobarbital and chlorzoxazone both increase sedation. Use Caution/Monitor.

• cilostazol

  pentobarbital will decrease the level or effect of cilostazol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• cinacalcet

  pentobarbital will decrease the level or effect of cinacalcet by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• cinnarizine

  cinnarizine and pentobarbital both increase sedation. Use Caution/Monitor.

• clemastine

  clemastine and pentobarbital both increase sedation. Use Caution/Monitor.

• clobazam

  pentobarbital, clobazam. Other (see comment). Use Caution/Monitor. Comment: Concomitant administration can increase the potential for CNS effects (e.g., increased sedation or respiratory depression).

• clomipramine

  pentobarbital will decrease the level or effect of clomipramine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.
  
  pentobarbital will decrease the level or effect of clomipramine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely.
  
  pentobarbital and clomipramine both increase sedation. Use Caution/Monitor.

• clonazepam

  pentobarbital and clonazepam both increase sedation. Use Caution/Monitor.

• clopidogrel

  pentobarbital will increase the level or effect of clopidogrel by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. CYP3A4 inducers may increase the metabolism of clopidogrel to its active metabolite. Monitor patients for potential increase in antiplatelet effects when CYP3A4 inducers are used in combination with clopidogrel

• clorazepate

  pentobarbital and clorazepate both increase sedation. Use Caution/Monitor.

• clozapine

  pentobarbital will decrease the level or effect of clozapine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.
  
  pentobarbital will decrease the level or effect of clozapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
  
  pentobarbital and clozapine both increase sedation. Use Caution/Monitor.

• codeine

  pentobarbital and codeine both increase sedation. Use Caution/Monitor.

• colchicine

  pentobarbital will decrease the level or effect of colchicine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• conivaptan

  pentobarbital will decrease the level or effect of conivaptan by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• conjugated estrogens

  pentobarbital will decrease the level or effect of conjugated estrogens by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• conjugated estrogens, vaginal

  pentobarbital will decrease the level or effect of conjugated estrogens, vaginal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• cortisone

  pentobarbital will decrease the level or effect of cortisone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• cyclizine

  cyclizine and pentobarbital both increase sedation. Use Caution/Monitor.

• cyclobenzaprine

  pentobarbital and cyclobenzaprine both increase sedation. Use Caution/Monitor.

• cyclophosphamide

  pentobarbital will decrease the level or effect of cyclophosphamide by affecting hepatic enzyme CYP2B6 metabolism. Use Caution/Monitor.

• cyclosporine

  pentobarbital will decrease the level or effect of cyclosporine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• cyproheptadine

  cyproheptadine and pentobarbital both increase sedation. Use Caution/Monitor.

• dantrolene

  pentobarbital and dantrolene both increase sedation. Use Caution/Monitor.

• daridorexant

  pentobarbital and daridorexant both increase sedation. Modify Therapy/Monitor Closely. Coadministration increases risk of CNS depression, which can lead to additive impairment of psychomotor performance and cause daytime impairment.

• darifenacin

  pentobarbital will decrease the level or effect of darifenacin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• darunavir

  pentobarbital will decrease the level or effect of darunavir by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• dasatinib

  pentobarbital will decrease the level or effect of dasatinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• desipramine

  pentobarbital and desipramine both increase sedation. Use Caution/Monitor.

• deutetrabenazine

  pentobarbital and deutetrabenazine both increase sedation. Use Caution/Monitor.

• dexamethasone

  pentobarbital will decrease the level or effect of dexamethasone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• dexchlorpheniramine

  dexchlorpheniramine and pentobarbital both increase sedation. Use Caution/Monitor.

• dexfenfluramine

  pentobarbital increases and dexfenfluramine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• dexmedetomidine

  pentobarbital and dexmedetomidine both increase sedation. Use Caution/Monitor.

• dexmethylphenidate

  pentobarbital increases and dexmethylphenidate decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• dextroamphetamine

  pentobarbital increases and dextroamphetamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• dextromoramide

  pentobarbital and dextromoramide both increase sedation. Use Caution/Monitor.

• diamorphine

  pentobarbital and diamorphine both increase sedation. Use Caution/Monitor.

• diazepam

  pentobarbital will decrease the level or effect of diazepam by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
  
  pentobarbital and diazepam both increase sedation. Use Caution/Monitor.

• diazepam intranasal

  pentobarbital will decrease the level or effect of diazepam intranasal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Strong or moderate CYP3A4 inducers may increase rate of diazepam elimination; therefore, efficacy of diazepam may be decreased.
  
  diazepam intranasal, pentobarbital. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Coadministration may potentiate the CNS-depressant effects of each drug.

• diethylpropion

  pentobarbital increases and diethylpropion decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• difelikefalin

  difelikefalin and pentobarbital both increase sedation. Use Caution/Monitor.

• difenoxin hcl

  pentobarbital and difenoxin hcl both increase sedation. Use Caution/Monitor.

• diltiazem

  pentobarbital will decrease the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• dimenhydrinate

  dimenhydrinate and pentobarbital both increase sedation. Use Caution/Monitor.

• diphenhydramine

  diphenhydramine and pentobarbital both increase sedation. Use Caution/Monitor.

• diphenoxylate hcl

  pentobarbital and diphenoxylate hcl both increase sedation. Use Caution/Monitor.

• dipipanone

  pentobarbital and dipipanone both increase sedation. Use Caution/Monitor.

• dobutamine

  pentobarbital increases and dobutamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• dopamine

  pentobarbital increases and dopamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• dopexamine

  pentobarbital increases and dopexamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• dosulepin

  pentobarbital and dosulepin both increase sedation. Use Caution/Monitor.

• doxepin

  pentobarbital and doxepin both increase sedation. Use Caution/Monitor.

• doxorubicin

  pentobarbital will decrease the level or effect of doxorubicin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• doxorubicin liposomal

  pentobarbital will decrease the level or effect of doxorubicin liposomal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• doxycycline

  pentobarbital decreases levels of doxycycline by increasing metabolism. Use Caution/Monitor.

• doxylamine

  pentobarbital and doxylamine both increase sedation. Use Caution/Monitor.

• dronabinol

  pentobarbital will decrease the level or effect of dronabinol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Dronabinol is a CYP3A4 substrate.

• droperidol

  pentobarbital and droperidol both increase sedation. Use Caution/Monitor.

• elagolix

  pentobarbital will decrease the level or effect of elagolix by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• eletriptan

  pentobarbital will decrease the level or effect of eletriptan by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• eltrombopag

  pentobarbital will decrease the level or effect of eltrombopag by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.
  
  pentobarbital will decrease the level or effect of eltrombopag by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.

• ephedrine

  pentobarbital increases and ephedrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• epinephrine

  pentobarbital increases and epinephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• epinephrine racemic

  pentobarbital increases and epinephrine racemic decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• erlotinib

  pentobarbital will decrease the level or effect of erlotinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• escitalopram

  pentobarbital will decrease the level or effect of escitalopram by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.

• esketamine intranasal

  esketamine intranasal, pentobarbital. Either increases toxicity of the other by sedation. Modify Therapy/Monitor Closely.

• esmolol

  pentobarbital decreases levels of esmolol by increasing metabolism. Use Caution/Monitor. Consider a higher beta-blocker dose during coadministration of pentobarbital. Atenolol, sotalol, nadolol less likely to be affected than other beta blockers.

• esomeprazole

  pentobarbital will decrease the level or effect of esomeprazole by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.

• estazolam

  pentobarbital and estazolam both increase sedation. Use Caution/Monitor.

• estradiol

  pentobarbital will decrease the level or effect of estradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• estradiol vaginal

  pentobarbital will decrease the level or effect of estradiol vaginal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• estrogens conjugated synthetic

  pentobarbital will decrease the level or effect of estrogens conjugated synthetic by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• estrogens esterified

  pentobarbital will decrease the level or effect of estrogens esterified by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• estropipate

  pentobarbital will decrease the level or effect of estropipate by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• ethanol

  pentobarbital and ethanol both increase sedation. Use Caution/Monitor.

• ethotoin

  pentobarbital will decrease the level or effect of ethotoin by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.

• etomidate

  etomidate and pentobarbital both increase sedation. Use Caution/Monitor.

• etonogestrel

  pentobarbital will decrease the level or effect of etonogestrel by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• etoposide

  pentobarbital will decrease the level or effect of etoposide by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• etravirine

  pentobarbital will decrease the level or effect of etravirine by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.
  
  pentobarbital will decrease the level or effect of etravirine by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.
  
  pentobarbital will decrease the level or effect of etravirine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• exemestane

  pentobarbital will decrease the level or effect of exemestane by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. For patients receiving exemestane with a potent CYP3A4 inducer the recommended dose of exemestane is 50 mg daily after a meal.

• felodipine

  pentobarbital will decrease the level or effect of felodipine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• fenfluramine

  pentobarbital increases and fenfluramine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• fentanyl

  pentobarbital will decrease the level or effect of fentanyl by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Coadministration of fentanyl with CYP3A4 inducers could lead to a decrease in fentanyl plasma concentrations, lack of efficacy or, possibly, development of a withdrawal syndrome in a patient who has developed physical dependence to fentanyl. After stopping a CYP3A4 inducer, as the effects of the inducer decline, the fentanyl plasma concentration will increase which could increase or prolong both the therapeutic and adverse effects.

• fentanyl intranasal

  pentobarbital will decrease the level or effect of fentanyl intranasal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Coadministration of fentanyl with CYP3A4 inducers could lead to a decrease in fentanyl plasma concentrations, lack of efficacy or, possibly, development of a withdrawal syndrome in a patient who has developed physical dependence to fentanyl. After stopping a CYP3A4 inducer, as the effects of the inducer decline, the fentanyl plasma concentration will increase which could increase or prolong both the therapeutic and adverse effects.

• fentanyl transdermal

  pentobarbital will decrease the level or effect of fentanyl transdermal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Coadministration of fentanyl with CYP3A4 inducers could lead to a decrease in fentanyl plasma concentrations, lack of efficacy or, possibly, development of a withdrawal syndrome in a patient who has developed physical dependence to fentanyl. After stopping a CYP3A4 inducer, as the effects of the inducer decline, the fentanyl plasma concentration will increase which could increase or prolong both the therapeutic and adverse effects.

• fentanyl transmucosal

  pentobarbital will decrease the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Coadministration of fentanyl with CYP3A4 inducers could lead to a decrease in fentanyl plasma concentrations, lack of efficacy or, possibly, development of a withdrawal syndrome in a patient who has developed physical dependence to fentanyl. After stopping a CYP3A4 inducer, as the effects of the inducer decline, the fentanyl plasma concentration will increase which could increase or prolong both the therapeutic and adverse effects.

• fesoterodine

  pentobarbital will decrease the level or effect of fesoterodine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• flibanserin

  pentobarbital will decrease the level or effect of flibanserin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Strong CYP3A4 inducers substantially decrease flibanserin systemic exposure.
  
  pentobarbital and flibanserin both increase sedation. Modify Therapy/Monitor Closely. Risk for sedation increased if flibanserin is coadministration with other CNS depressants.

• fludrocortisone

  pentobarbital will decrease the level or effect of fludrocortisone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• fluphenazine

  pentobarbital and fluphenazine both increase sedation. Use Caution/Monitor.

• flurazepam

  pentobarbital and flurazepam both increase sedation. Use Caution/Monitor.

• formoterol

  pentobarbital increases and formoterol decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• fosamprenavir

  pentobarbital will decrease the level or effect of fosamprenavir by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• fosaprepitant

  pentobarbital will decrease the level or effect of fosaprepitant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• fosphenytoin

  pentobarbital will decrease the level or effect of fosphenytoin by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.

• gabapentin

  gabapentin, pentobarbital. Either increases effects of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of CNS depressants can result in serious, life-threatening, and fatal respiratory depression. Use lowest dose possible and monitor for respiratory depression and sedation.

• gabapentin enacarbil

  gabapentin enacarbil, pentobarbital. Either increases effects of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of CNS depressants can result in serious, life-threatening, and fatal respiratory depression. Use lowest dose possible and monitor for respiratory depression and sedation.

• ganaxolone

  pentobarbital and ganaxolone both increase sedation. Use Caution/Monitor.

• gefitinib

  pentobarbital will decrease the level or effect of gefitinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Increase gefitinib to 500 mg daily if coadministered with a strong CYP3A4 inducer. Resume gefitinib dose at 250 mg/day 7 days after discontinuing the strong inducer.

• glecaprevir/pibrentasvir

  pentobarbital will decrease the level or effect of glecaprevir/pibrentasvir by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Coadministration of drugs that induce CYP3A4 with glecaprevir/pibrentasvir may decrease glecaprevir/pibrentasvir plasma concentrations. Potential for loss of therapeutic effect.

• gotu kola

  gotu kola increases effects of pentobarbital by pharmacodynamic synergism. Use Caution/Monitor. May enhance CNS depression.

• guanfacine

  pentobarbital will decrease the level or effect of guanfacine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Strong or moderate CYP3A4 inducers significantly reduce guanfacine plasma concentrations and elimination half-life. If coadministered, more frequent dosing of the IR product may be required to achieve or maintain the desired hypotensive response. For patients with ADHD, FDA-approved labeling for ER guanfacine recommends that, if coadministered, doubling the recommended dose of guanfacine should be considered.

• haloperidol

  pentobarbital and haloperidol both increase sedation. Use Caution/Monitor.

• hawthorn

  hawthorn increases effects of pentobarbital by pharmacodynamic synergism. Use Caution/Monitor. May enhance CNS depression.

• hemin

  pentobarbital decreases effects of hemin by pharmacodynamic antagonism. Use Caution/Monitor. Drugs that increase delta-aminolevulinic acid synthetase may decrease hemin effect.

• hops

  hops increases effects of pentobarbital by pharmacodynamic synergism. Use Caution/Monitor. May enhance CNS depression.

• hydrocodone

  pentobarbital will decrease the level or effect of hydrocodone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Caution when discontinuing CYP3A4 inducers that are coadministered with hydrocodone; plasma concentrations of hydrocodone may increase and can result in potentially fatal respiratory depression

• hydrocortisone

  pentobarbital will decrease the level or effect of hydrocortisone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• hydromorphone

  pentobarbital and hydromorphone both increase sedation. Use Caution/Monitor.

• hydroxyprogesterone caproate (DSC)

  pentobarbital will decrease the level or effect of hydroxyprogesterone caproate (DSC) by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• hydroxyzine

  hydroxyzine and pentobarbital both increase sedation. Use Caution/Monitor.

• ifosfamide

  pentobarbital increases effects of ifosfamide by affecting hepatic enzyme CYP2B6 metabolism. Use Caution/Monitor. Coadministration of ifosfamide with CYP2B6 inducers may increase metabolism of ifosfamide to its metabolite. Monitor for increased effects/toxicities if combined with CYP2B6 inducers.
  
  pentobarbital increases toxicity of ifosfamide by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. CYP3A4 inducers may increase the metabolism of ifosfamide to its active alkylating metabolites. CYP3A4 inducers may increase the formation of the neurotoxic/nephrotoxic ifosfamide metabolite, chloroacetaldehyde. Closely monitor patients taking ifosfamide with CYP3A4 inducers for toxicities and consider dose adjustment.

• iloperidone

  pentobarbital will decrease the level or effect of iloperidone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
  
  pentobarbital and iloperidone both increase sedation. Use Caution/Monitor.

• imipramine

  pentobarbital will decrease the level or effect of imipramine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.
  
  pentobarbital will decrease the level or effect of imipramine by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.
  
  pentobarbital will decrease the level or effect of imipramine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely.
  
  pentobarbital and imipramine both increase sedation. Use Caution/Monitor.

• indinavir

  pentobarbital will decrease the level or effect of indinavir by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• irinotecan

  pentobarbital will decrease the level or effect of irinotecan by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• irinotecan liposomal

  pentobarbital will decrease the level or effect of irinotecan liposomal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• isoproterenol

  pentobarbital increases and isoproterenol decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• ixabepilone

  pentobarbital will decrease the level or effect of ixabepilone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• kava

  kava increases effects of pentobarbital by pharmacodynamic synergism. Use Caution/Monitor. May enhance CNS depression.

• ketamine

  ketamine and pentobarbital both increase sedation. Use Caution/Monitor.

• ketotifen, ophthalmic

  pentobarbital and ketotifen, ophthalmic both increase sedation. Use Caution/Monitor.

• labetalol

  pentobarbital decreases levels of labetalol by increasing metabolism. Use Caution/Monitor. Consider a higher beta-blocker dose during coadministration of pentobarbital. Atenolol, sotalol, nadolol less likely to be affected than other beta blockers.

• lapatinib

  pentobarbital will decrease the level or effect of lapatinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• lasmiditan

  lasmiditan, pentobarbital. Either increases effects of the other by sedation. Use Caution/Monitor. Coadministration of lasmiditan and other CNS depressant drugs, including alcohol have not been evaluated in clinical studies. Lasmiditan may cause sedation, as well as other cognitive and/or neuropsychiatric adverse reactions.

• levalbuterol

  pentobarbital increases and levalbuterol decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• levamlodipine

  pentobarbital will decrease the level or effect of levamlodipine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. No information is available on the quantitative effects of CYP3A4 inducers on amlodipine. Closely monitor blood pressure when amlodipine is coadministered with CYP3A4 inducers.

• levonorgestrel intrauterine

  pentobarbital decreases levels of levonorgestrel intrauterine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• levonorgestrel oral

  pentobarbital decreases levels of levonorgestrel oral by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• levonorgestrel oral/ethinylestradiol/ferrous bisglycinate

  pentobarbital will decrease the level or effect of levonorgestrel oral/ethinylestradiol/ferrous bisglycinate by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. The efficacy of hormonal contraceptives may be reduced. Use an alternative method of contraception or a backup method when enzyme inducers are used with combined hormonal contraceptives (CHCs), and continue backup contraception for 28 days after discontinuing enzyme inducer to ensure contraceptive reliability.

• levorphanol

  pentobarbital and levorphanol both increase sedation. Use Caution/Monitor.

• lidocaine

  pentobarbital will decrease the level or effect of lidocaine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.

• linagliptin

  pentobarbital will decrease the level or effect of linagliptin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Use of alternative treatments is strongly recommended when linagliptin is to be administered with a CYP3A4 inducer

• lisdexamfetamine

  pentobarbital increases and lisdexamfetamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• lofepramine

  pentobarbital and lofepramine both increase sedation. Use Caution/Monitor.

• lofexidine

  pentobarbital and lofexidine both increase sedation. Use Caution/Monitor.

• lopinavir

  pentobarbital will decrease the level or effect of lopinavir by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• loprazolam

  pentobarbital and loprazolam both increase sedation. Use Caution/Monitor.

• loratadine

  pentobarbital will decrease the level or effect of loratadine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• lorazepam

  pentobarbital and lorazepam both increase sedation. Use Caution/Monitor.

• lormetazepam

  pentobarbital and lormetazepam both increase sedation. Use Caution/Monitor.

• loxapine

  pentobarbital and loxapine both increase sedation. Use Caution/Monitor.

• loxapine inhaled

  pentobarbital and loxapine inhaled both increase sedation. Use Caution/Monitor.

• lurasidone

  lurasidone, pentobarbital. Either increases toxicity of the other by Other (see comment). Use Caution/Monitor. Comment: Potential for increased CNS depressant effects when used concurrently; monitor for increased adverse effects and toxicity.

• maprotiline

  pentobarbital and maprotiline both increase sedation. Use Caution/Monitor.

• maraviroc

  pentobarbital will decrease the level or effect of maraviroc by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• marijuana

  pentobarbital and marijuana both increase sedation. Use Caution/Monitor.

• medroxyprogesterone

  pentobarbital will decrease the level or effect of medroxyprogesterone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Contraceptirve failure possible. Use alternative if available.

• melatonin

  pentobarbital and melatonin both increase sedation. Use Caution/Monitor.

• meperidine

  pentobarbital and meperidine both increase sedation. Use Caution/Monitor.

• meprobamate

  pentobarbital and meprobamate both increase sedation. Use Caution/Monitor.

• mestranol

  pentobarbital will decrease the level or effect of mestranol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• metaproterenol

  pentobarbital increases and metaproterenol decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• metaxalone

  pentobarbital and metaxalone both increase sedation. Use Caution/Monitor.

• methadone

  pentobarbital will decrease the level or effect of methadone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
  
  pentobarbital and methadone both increase sedation. Use Caution/Monitor.

• methamphetamine

  pentobarbital increases and methamphetamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• methocarbamol

  pentobarbital and methocarbamol both increase sedation. Use Caution/Monitor.

• methylenedioxymethamphetamine

  pentobarbital increases and methylenedioxymethamphetamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• methylprednisolone

  pentobarbital will decrease the level or effect of methylprednisolone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• metoprolol

  pentobarbital decreases levels of metoprolol by increasing metabolism. Use Caution/Monitor. Consider a higher beta-blocker dose during coadministration of pentobarbital. Atenolol, sotalol, nadolol less likely to be affected than other beta blockers.

• mexiletine

  pentobarbital will decrease the level or effect of mexiletine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.

• midazolam

  pentobarbital will decrease the level or effect of midazolam by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
  
  pentobarbital and midazolam both increase sedation. Use Caution/Monitor.

• midazolam intranasal

  midazolam intranasal, pentobarbital. Either increases toxicity of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Concomitant use of barbiturates, alcohol, or other CNS depressants may increase the risk of hypoventilation, airway obstruction, desaturation, or apnea and may contribute to profound and/or prolonged drug effect.

• midodrine

  pentobarbital increases and midodrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• mifepristone

  pentobarbital will decrease the level or effect of mifepristone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. CYP3A4 inducers have not been studied, coadministration not recommended by manufacturer

• mirtazapine

  pentobarbital and mirtazapine both increase sedation. Use Caution/Monitor.

• modafinil

  pentobarbital increases and modafinil decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• morphine

  pentobarbital and morphine both increase sedation. Use Caution/Monitor.

• motherwort

  pentobarbital and motherwort both increase sedation. Use Caution/Monitor.

• moxonidine

  pentobarbital and moxonidine both increase sedation. Use Caution/Monitor.

• nabilone

  pentobarbital and nabilone both increase sedation. Use Caution/Monitor.

• nadolol

  pentobarbital decreases levels of nadolol by increasing metabolism. Use Caution/Monitor. Atenolol, sotalol, nadolol less likely to be affected than other beta blockers.

• nalbuphine

  pentobarbital and nalbuphine both increase sedation. Use Caution/Monitor.

• nateglinide

  pentobarbital will decrease the level or effect of nateglinide by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.

• nebivolol

  pentobarbital decreases levels of nebivolol by increasing metabolism. Use Caution/Monitor. Consider a higher beta-blocker dose during coadministration of pentobarbital. Atenolol, sotalol, nadolol less likely to be affected than other beta blockers.

• nelfinavir

  pentobarbital will decrease the level or effect of nelfinavir by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• nicardipine

  pentobarbital will decrease the level or effect of nicardipine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• nifedipine

  pentobarbital will decrease the level or effect of nifedipine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely.

• nilotinib

  pentobarbital will decrease the level or effect of nilotinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• nisoldipine

  pentobarbital will decrease the level or effect of nisoldipine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• norepinephrine

  pentobarbital increases and norepinephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• nortriptyline

  pentobarbital and nortriptyline both increase sedation. Use Caution/Monitor.

• olanzapine

  pentobarbital will decrease the level or effect of olanzapine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.
  
  pentobarbital and olanzapine both increase sedation. Use Caution/Monitor.

• oliceridine

  pentobarbital will decrease the level or effect of oliceridine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. If coadministration with a CYP3A4 inducer is necessary, consider increasing oliceridine dose until stable drug effects are achieved; monitor for signs of opioid withdrawal. If inducer is discontinued, consider oliceridine dosage reduction and monitor for signs of respiratory depression.
  
  oliceridine, pentobarbital. Either increases toxicity of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Profound sedation, respiratory depression, coma, and death may result if coadministered. Reserve concomitant prescribing of these drugs in patients for whom other treatment options are inadequate. Limit dosages and durations to the minimum required. Monitor closely for signs of respiratory depression and sedation.

• omeprazole

  pentobarbital will decrease the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.

• ondansetron

  pentobarbital will decrease the level or effect of ondansetron by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. No dosage adjustment for ondansetron is recommended for patients on these drugs.

• opium tincture

  pentobarbital and opium tincture both increase sedation. Use Caution/Monitor.

• orphenadrine

  pentobarbital and orphenadrine both increase sedation. Use Caution/Monitor.

• osilodrostat

  pentobarbital will decrease the level or effect of osilodrostat by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Monitor cortisol concentration and patient?s signs and symptoms during coadministration or discontinuation with strong CYP3A4 inducers. Adjust dose of osilodrostat if necessary.

• ospemifene

  pentobarbital decreases levels of ospemifene by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• oxazepam

  pentobarbital and oxazepam both increase sedation. Use Caution/Monitor.

• oxycodone

  pentobarbital and oxycodone both increase sedation. Use Caution/Monitor.
  
  pentobarbital decreases levels of oxycodone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• oxymorphone

  pentobarbital and oxymorphone both increase sedation. Use Caution/Monitor.

• paliperidone

  pentobarbital and paliperidone both increase sedation. Use Caution/Monitor.

• papaveretum

  pentobarbital and papaveretum both increase sedation. Use Caution/Monitor.

• papaverine

  pentobarbital and papaverine both increase sedation. Use Caution/Monitor.

• parecoxib

  pentobarbital will decrease the level or effect of parecoxib by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.

• passion flower

  passion flower increases effects of pentobarbital by pharmacodynamic synergism. Use Caution/Monitor. May enhance CNS depression.

• pazopanib

  pentobarbital will decrease the level or effect of pazopanib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• penbutolol

  pentobarbital decreases levels of penbutolol by increasing metabolism. Use Caution/Monitor. Consider a higher beta-blocker dose during coadministration of pentobarbital. Atenolol, sotalol, nadolol less likely to be affected than other beta blockers.

• pentazocine

  pentobarbital and pentazocine both increase sedation. Use Caution/Monitor.

• perphenazine

  pentobarbital and perphenazine both increase sedation. Use Caution/Monitor.

• phendimetrazine

  pentobarbital increases and phendimetrazine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• phenobarbital

  pentobarbital and phenobarbital both increase sedation. Use Caution/Monitor.

• phentermine

  pentobarbital increases and phentermine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• phenylephrine

  pentobarbital increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• phenylephrine PO

  pentobarbital increases and phenylephrine PO decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. .

• phenytoin

  pentobarbital will decrease the level or effect of phenytoin by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.

• pholcodine

  pentobarbital and pholcodine both increase sedation. Use Caution/Monitor.

• pimavanserin

  pentobarbital will decrease the level or effect of pimavanserin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Avoid coadministration if possible. Monitor for reduced pimavanserin efficacy. An increase in pimavanserin dosage may be needed.

• pimozide

  pentobarbital and pimozide both increase sedation. Use Caution/Monitor.

• pindolol

  pentobarbital decreases levels of pindolol by increasing metabolism. Use Caution/Monitor. Consider a higher beta-blocker dose during coadministration of pentobarbital. Atenolol, sotalol, nadolol less likely to be affected than other beta blockers.

• pirbuterol

  pentobarbital increases and pirbuterol decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• pitolisant

  pentobarbital will decrease the level or effect of pitolisant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Pitolisant exposure is decreased by 50% if coadministered with strong CYP3A4 inducers. For patients stable on pitolisant 8.9 mg/day or 17.8 mg/day, double the pitolisant dose (ie, 17.8 mg or 35.6 mg, respectively) over 7 days. If the strong CYP3A4 inducer is discontinued, reduce pitolisant dosage by half.

• polatuzumab vedotin

  pentobarbital will decrease the level or effect of polatuzumab vedotin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Polatuzumab undergoes catabolism to small peptides, amino acids, monomethyl auristatin E (MMAE), and unconjugated MMAE-related catabolites. MMAE is a CYP3A4 substrate. Coadministration of polatuzumab vedotin with a strong CYP3A4 inducer may decrease unconjugated MMAE AUC.

• prednisone

  pentobarbital will decrease the level or effect of prednisone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• pregabalin

  pregabalin, pentobarbital. Either increases effects of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of CNS depressants can result in serious, life-threatening, and fatal respiratory depression. Use lowest dose possible and monitor for respiratory depression and sedation.

• primidone

  pentobarbital and primidone both increase sedation. Use Caution/Monitor.

• prochlorperazine

  pentobarbital and prochlorperazine both increase sedation. Use Caution/Monitor.

• promethazine

  promethazine and pentobarbital both increase sedation. Use Caution/Monitor.

• propafenone

  pentobarbital decreases levels of propafenone by increasing metabolism. Use Caution/Monitor.

• propofol

  propofol and pentobarbital both increase sedation. Use Caution/Monitor.

• propranolol

  pentobarbital decreases levels of propranolol by increasing metabolism. Use Caution/Monitor. Consider a higher beta-blocker dose during coadministration of pentobarbital. Atenolol, sotalol, nadolol less likely to be affected than other beta blockers.

• propylhexedrine

  pentobarbital increases and propylhexedrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• protriptyline

  pentobarbital and protriptyline both increase sedation. Use Caution/Monitor.

• quazepam

  pentobarbital and quazepam both increase sedation. Use Caution/Monitor.

• quetiapine

  pentobarbital will decrease the level or effect of quetiapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
  
  pentobarbital and quetiapine both increase sedation. Use Caution/Monitor.

• quinidine

  pentobarbital will decrease the level or effect of quinidine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• ramelteon

  pentobarbital will decrease the level or effect of ramelteon by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.
  
  pentobarbital and ramelteon both increase sedation. Use Caution/Monitor.

• remimazolam

  remimazolam, pentobarbital. Either increases toxicity of the other by sedation. Modify Therapy/Monitor Closely. Coadministration may result in profound sedation, respiratory depression, coma, and/or death. Continuously monitor vital signs during sedation and recovery period if coadministered. Carefully titrate remimazolam dose if administered with opioid analgesics and/or sedative/hypnotics.

• repaglinide

  pentobarbital will decrease the level or effect of repaglinide by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• rifampin

  rifampin decreases levels of pentobarbital by increasing metabolism. Use Caution/Monitor.

• riociguat

  pentobarbital will decrease the level or effect of riociguat by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Data not available for dose adjustment

• risperidone

  pentobarbital and risperidone both increase sedation. Use Caution/Monitor.

• ritonavir

  pentobarbital will decrease the level or effect of ritonavir by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• salmeterol

  pentobarbital increases and salmeterol decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• saquinavir

  pentobarbital will decrease the level or effect of saquinavir by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• scullcap

  pentobarbital and scullcap both increase sedation. Use Caution/Monitor.

• secobarbital

  pentobarbital and secobarbital both increase sedation. Use Caution/Monitor.

• sevoflurane

  sevoflurane and pentobarbital both increase sedation. Use Caution/Monitor.

• shepherd's purse

  pentobarbital and shepherd's purse both increase sedation. Use Caution/Monitor.

• solifenacin

  pentobarbital will decrease the level or effect of solifenacin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• sorafenib

  pentobarbital decreases levels of sorafenib by increasing metabolism. Use Caution/Monitor.

• sotalol

  pentobarbital decreases levels of sotalol by increasing metabolism. Use Caution/Monitor. Consider a higher beta-blocker dose during coadministration of pentobarbital. Atenolol, sotalol, nadolol less likely to be affected than other beta blockers.

• stiripentol

  stiripentol, pentobarbital. Either increases effects of the other by sedation. Use Caution/Monitor. Concomitant use stiripentol with other CNS depressants, including alcohol, may increase the risk of sedation and somnolence.

• sufentanil

  pentobarbital and sufentanil both increase sedation. Use Caution/Monitor.

• sufentanil SL

  pentobarbital decreases effects of sufentanil SL by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Coadministration of CYP3A4 inducers may decrease sufentanil levels and efficacy, possibly precipitating withdrawal syndrome in patients who have developed physical dependence to sufentanil. Discontinuation of concomitantly used CYP3A4 inducers may increase sufentanil plasma concentration.

• sunitinib

  pentobarbital will decrease the level or effect of sunitinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• suvorexant

  suvorexant and pentobarbital both increase sedation. Modify Therapy/Monitor Closely. Dosage adjustments of suvorexant and concomitant CNS depressants may be necessary
  
  pentobarbital will decrease the level or effect of suvorexant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Strong CYP3A4 inducers may decrease suvorexant efficacy; if increased suvorexant dose required, do not exceed 20 mg/day

• tacrolimus

  pentobarbital will decrease the level or effect of tacrolimus by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• tadalafil

  pentobarbital will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Avoid combination in pulmonary HTN patients. For patients with ED, monitor response to tadalafil carefully because of potential for decreased effectiveness.

• tamoxifen

  pentobarbital will decrease the level or effect of tamoxifen by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.
  
  pentobarbital will decrease the level or effect of tamoxifen by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• tapentadol

  pentobarbital and tapentadol both increase sedation. Use Caution/Monitor.

• tasimelteon

  pentobarbital will decrease the level or effect of tasimelteon by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Avoid coadministration of tasimelteon with strong CYP3A4 inducers

• temazepam

  pentobarbital and temazepam both increase sedation. Use Caution/Monitor.

• temsirolimus

  pentobarbital will decrease the level or effect of temsirolimus by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• terbinafine

  pentobarbital will decrease the level or effect of terbinafine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• terbutaline

  pentobarbital increases and terbutaline decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• thalidomide

  thalidomide increases effects of pentobarbital by unspecified interaction mechanism. Use Caution/Monitor. Increased sedative effects.

• theophylline

  pentobarbital will decrease the level or effect of theophylline by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.
  
  pentobarbital will decrease the level or effect of theophylline by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• thioridazine

  pentobarbital and thioridazine both increase sedation. Use Caution/Monitor.

• thiothixene

  pentobarbital and thiothixene both increase sedation. Use Caution/Monitor.

• timolol

  pentobarbital decreases levels of timolol by increasing metabolism. Use Caution/Monitor. Consider a higher beta-blocker dose during coadministration of pentobarbital. Atenolol, sotalol, nadolol less likely to be affected than other beta blockers.

• tinidazole

  pentobarbital will decrease the level or effect of tinidazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• tipranavir

  pentobarbital will decrease the level or effect of tipranavir by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• tofacitinib

  pentobarbital will decrease the level or effect of tofacitinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Loss of, or decreased response to tofacitinib may occur when coadministered with potent CYP3A4 inducers

• tolterodine

  pentobarbital will decrease the level or effect of tolterodine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• topiramate

  pentobarbital and topiramate both increase sedation. Modify Therapy/Monitor Closely.

• toremifene

  pentobarbital decreases levels of toremifene by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. CYP3A4 inducers increase rate of toremifene metabolism, lowering the steady-state concentration in serum.

• tramadol

  pentobarbital and tramadol both increase sedation. Use Caution/Monitor.
  
  pentobarbital will decrease the level or effect of tramadol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Decreased AUC of tramadol and the active metabolite (O-desmethyltramadol) when coadministered with strong CYP3A4 and CYP2B6 inducers

• trazodone

  pentobarbital will decrease the level or effect of trazodone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
  
  pentobarbital and trazodone both increase sedation. Use Caution/Monitor.

• triamcinolone acetonide injectable suspension

  pentobarbital will decrease the level or effect of triamcinolone acetonide injectable suspension by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• triazolam

  pentobarbital will decrease the level or effect of triazolam by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
  
  pentobarbital and triazolam both increase sedation. Use Caution/Monitor.

• triclofos

  pentobarbital and triclofos both increase sedation. Use Caution/Monitor.

• trifluoperazine

  pentobarbital and trifluoperazine both increase sedation. Use Caution/Monitor.

• trimipramine

  pentobarbital and trimipramine both increase sedation. Use Caution/Monitor.

• triprolidine

  triprolidine and pentobarbital both increase sedation. Use Caution/Monitor.

• vardenafil

  pentobarbital will decrease the level or effect of vardenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• verapamil

  pentobarbital will decrease the level or effect of verapamil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• vilazodone

  pentobarbital decreases levels of vilazodone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Consider increasing vilazodone dose up to 2-fold (not to exceed 80 mg/day) when coadministered with strong CYP3A4 inducers for >14 days.

• vortioxetine

  pentobarbital increases levels of vortioxetine by increasing metabolism. Modify Therapy/Monitor Closely. Consider increasing the vortioxetine dose when coadministered with strong CYP inducers for >14 days; not to exceed 3 times original vortioxetine dose.

• warfarin

  pentobarbital will decrease the level or effect of warfarin by Other (see comment). Use Caution/Monitor. Warfarin's less potent R-enantiomer is metabolized in part by CYP3A4 (and also CYP1A2 and CYP2C19). Monitor INR more frequently if coadministered with inducers of these isoenzymes and adjust warfarin dose if needed.

• xylometazoline

  pentobarbital increases and xylometazoline decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• yohimbine

  pentobarbital increases and yohimbine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• ziconotide

  pentobarbital and ziconotide both increase sedation. Use Caution/Monitor.

• ziprasidone

  pentobarbital and ziprasidone both increase sedation. Use Caution/Monitor.

• zotepine

  pentobarbital and zotepine both increase sedation. Use Caution/Monitor.

Minor (116)

• acetazolamide

  acetazolamide, pentobarbital. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Increased risk of anticonvulsant induced osteomalacia.

• alfentanil

  pentobarbital will decrease the level or effect of alfentanil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• alfuzosin

  pentobarbital will decrease the level or effect of alfuzosin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• alosetron

  pentobarbital will decrease the level or effect of alosetron by affecting hepatic enzyme CYP2C9/10 metabolism. Minor/Significance Unknown.
  
  pentobarbital will decrease the level or effect of alosetron by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• ambrisentan

  pentobarbital will decrease the level or effect of ambrisentan by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• amitriptyline

  pentobarbital, amitriptyline. Other (see comment). Minor/Significance Unknown. Comment: Barbiturates may increase adverse effects, including respiratory depression, produced by toxic doses of TCAs. With therapeutic doses of TCAs, barbiturates increase metabolism and decrease blood concentrations of TCAs.

• amoxapine

  pentobarbital, amoxapine. Other (see comment). Minor/Significance Unknown. Comment: Barbiturates may increase adverse effects, including respiratory depression, produced by toxic doses of TCAs. With therapeutic doses of TCAs, barbiturates increase metabolism and decrease blood concentrations of TCAs.

• amphotericin B deoxycholate

  pentobarbital decreases levels of amphotericin B deoxycholate by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.

• antipyrine

  pentobarbital will decrease the level or effect of antipyrine by affecting hepatic enzyme CYP1A2 metabolism. Minor/Significance Unknown.

• armodafinil

  pentobarbital will decrease the level or effect of armodafinil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• asenapine

  pentobarbital will decrease the level or effect of asenapine by affecting hepatic enzyme CYP1A2 metabolism. Minor/Significance Unknown.

• ashwagandha

  ashwagandha increases effects of pentobarbital by pharmacodynamic synergism. Minor/Significance Unknown. May enhance CNS depression.

• atazanavir

  pentobarbital will decrease the level or effect of atazanavir by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• bosentan

  pentobarbital will decrease the level or effect of bosentan by affecting hepatic enzyme CYP2C9/10 metabolism. Minor/Significance Unknown.
  
  pentobarbital will decrease the level or effect of bosentan by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• brimonidine

  brimonidine increases effects of pentobarbital by pharmacodynamic synergism. Minor/Significance Unknown. Increased CNS depression.

• brinzolamide

  brinzolamide, pentobarbital. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Increased risk of anticonvulsant induced osteomalacia.

• caffeine

  pentobarbital will decrease the level or effect of caffeine by affecting hepatic enzyme CYP1A2 metabolism. Minor/Significance Unknown.

• celecoxib

  pentobarbital will decrease the level or effect of celecoxib by affecting hepatic enzyme CYP2C9/10 metabolism. Minor/Significance Unknown.

• cevimeline

  pentobarbital will decrease the level or effect of cevimeline by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• chloramphenicol

  pentobarbital decreases levels of chloramphenicol by increasing metabolism. Minor/Significance Unknown.

• chlorpromazine

  pentobarbital decreases levels of chlorpromazine by increasing metabolism. Minor/Significance Unknown.

• cimetidine

  pentobarbital will decrease the level or effect of cimetidine by affecting hepatic enzyme CYP2C19 metabolism. Minor/Significance Unknown.

• clarithromycin

  pentobarbital will decrease the level or effect of clarithromycin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.
  
  pentobarbital decreases levels of clarithromycin by increasing elimination. Minor/Significance Unknown.

• clomipramine

  pentobarbital, clomipramine. Other (see comment). Minor/Significance Unknown. Comment: Barbiturates may increase adverse effects, including respiratory depression, produced by toxic doses of TCAs. With therapeutic doses of TCAs, barbiturates increase metabolism and decrease blood concentrations of TCAs.

• clotrimazole

  pentobarbital decreases levels of clotrimazole by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.

• cocaine topical

  pentobarbital will decrease the level or effect of cocaine topical by affecting hepatic enzyme CYP2B6 metabolism. Minor/Significance Unknown.

• dapsone

  pentobarbital will decrease the level or effect of dapsone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• desipramine

  pentobarbital, desipramine. Other (see comment). Minor/Significance Unknown. Comment: Barbiturates may increase adverse effects, including respiratory depression, produced by toxic doses of TCAs. With therapeutic doses of TCAs, barbiturates increase metabolism and decrease blood concentrations of TCAs.

• diclofenac

  pentobarbital will decrease the level or effect of diclofenac by affecting hepatic enzyme CYP2C9/10 metabolism. Minor/Significance Unknown.

• disopyramide

  pentobarbital will decrease the level or effect of disopyramide by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• docetaxel

  pentobarbital will decrease the level or effect of docetaxel by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• donepezil

  pentobarbital will decrease the level or effect of donepezil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• dosulepin

  pentobarbital, dosulepin. Other (see comment). Minor/Significance Unknown. Comment: Barbiturates may increase adverse effects, including respiratory depression, produced by toxic doses of TCAs. With therapeutic doses of TCAs, barbiturates increase metabolism and decrease blood concentrations of TCAs.

• doxepin

  pentobarbital, doxepin. Other (see comment). Minor/Significance Unknown. Comment: Barbiturates may increase adverse effects, including respiratory depression, produced by toxic doses of TCAs. With therapeutic doses of TCAs, barbiturates increase metabolism and decrease blood concentrations of TCAs.

• dutasteride

  pentobarbital will decrease the level or effect of dutasteride by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• efavirenz

  pentobarbital will decrease the level or effect of efavirenz by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• eplerenone

  pentobarbital will decrease the level or effect of eplerenone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• erythromycin base

  pentobarbital decreases levels of erythromycin base by increasing elimination. Minor/Significance Unknown.

• erythromycin ethylsuccinate

  pentobarbital decreases levels of erythromycin ethylsuccinate by increasing elimination. Minor/Significance Unknown.

• erythromycin lactobionate

  pentobarbital decreases levels of erythromycin lactobionate by increasing elimination. Minor/Significance Unknown.

• erythromycin stearate

  pentobarbital decreases levels of erythromycin stearate by increasing elimination. Minor/Significance Unknown.

• ethosuximide

  ethosuximide decreases effects of pentobarbital by pharmacodynamic antagonism. Minor/Significance Unknown.

• eucalyptus

  pentobarbital will decrease the level or effect of eucalyptus by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.
  
  pentobarbital and eucalyptus both increase sedation. Minor/Significance Unknown.

• finasteride

  pentobarbital will decrease the level or effect of finasteride by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• fluconazole

  pentobarbital decreases levels of fluconazole by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.

• flurbiprofen

  pentobarbital will decrease the level or effect of flurbiprofen by affecting hepatic enzyme CYP2C9/10 metabolism. Minor/Significance Unknown.

• frovatriptan

  pentobarbital will decrease the level or effect of frovatriptan by affecting hepatic enzyme CYP1A2 metabolism. Minor/Significance Unknown.

• galantamine

  pentobarbital will decrease the level or effect of galantamine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• griseofulvin

  pentobarbital decreases levels of griseofulvin by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.

• haloperidol

  haloperidol, pentobarbital. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Risk of hyperthermia if haloperidol admin. during barbiturate withdrawal.

• ibuprofen

  pentobarbital will decrease the level or effect of ibuprofen by affecting hepatic enzyme CYP2C9/10 metabolism. Minor/Significance Unknown.

• ibuprofen IV

  pentobarbital will decrease the level or effect of ibuprofen IV by affecting hepatic enzyme CYP2C9/10 metabolism. Minor/Significance Unknown.

• imatinib

  pentobarbital will decrease the level or effect of imatinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• imipramine

  pentobarbital, imipramine. Other (see comment). Minor/Significance Unknown. Comment: Barbiturates may increase adverse effects, including respiratory depression, produced by toxic doses of TCAs. With therapeutic doses of TCAs, barbiturates increase metabolism and decrease blood concentrations of TCAs.

• isocarboxazid

  isocarboxazid increases levels of pentobarbital by decreasing metabolism. Minor/Significance Unknown. Theoretical interaction.

• isradipine

  pentobarbital will decrease the level or effect of isradipine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• itraconazole

  pentobarbital will decrease the level or effect of itraconazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.
  
  pentobarbital decreases levels of itraconazole by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.

• ketoconazole

  pentobarbital will decrease the level or effect of ketoconazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.
  
  pentobarbital decreases levels of ketoconazole by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.

• lansoprazole

  pentobarbital will decrease the level or effect of lansoprazole by affecting hepatic enzyme CYP2C19 metabolism. Minor/Significance Unknown.

• levoketoconazole

  pentobarbital will decrease the level or effect of levoketoconazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.
  
  pentobarbital decreases levels of levoketoconazole by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.

• levothyroxine

  pentobarbital decreases levels of levothyroxine by increasing metabolism. Minor/Significance Unknown.

• linezolid

  linezolid increases levels of pentobarbital by decreasing metabolism. Minor/Significance Unknown. Theoretical interaction.

• liothyronine

  pentobarbital decreases levels of liothyronine by increasing metabolism. Minor/Significance Unknown.

• lofepramine

  pentobarbital, lofepramine. Other (see comment). Minor/Significance Unknown. Comment: Barbiturates may increase adverse effects, including respiratory depression, produced by toxic doses of TCAs. With therapeutic doses of TCAs, barbiturates increase metabolism and decrease blood concentrations of TCAs.

• losartan

  pentobarbital will decrease the level or effect of losartan by affecting hepatic enzyme CYP2C9/10 metabolism. Minor/Significance Unknown.

• maprotiline

  pentobarbital, maprotiline. Other (see comment). Minor/Significance Unknown. Comment: Barbiturates may increase adverse effects, including respiratory depression, produced by toxic doses of TCAs. With therapeutic doses of TCAs, barbiturates increase metabolism and decrease blood concentrations of TCAs.

• meloxicam

  pentobarbital will decrease the level or effect of meloxicam by affecting hepatic enzyme CYP2C9/10 metabolism. Minor/Significance Unknown.

• methazolamide

  methazolamide, pentobarbital. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Increased risk of anticonvulsant induced osteomalacia.

• methsuximide

  methsuximide decreases effects of pentobarbital by pharmacodynamic antagonism. Minor/Significance Unknown.

• miconazole vaginal

  pentobarbital decreases levels of miconazole vaginal by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.

• montelukast

  pentobarbital will decrease the level or effect of montelukast by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• nettle

  nettle increases effects of pentobarbital by pharmacodynamic synergism. Minor/Significance Unknown. (High dose nettle; theoretical interaction) May enhance CNS depression.

• nimodipine

  pentobarbital will decrease the level or effect of nimodipine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• nitrendipine

  pentobarbital will decrease the level or effect of nitrendipine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• nortriptyline

  pentobarbital, nortriptyline. Other (see comment). Minor/Significance Unknown. Comment: Barbiturates may increase adverse effects, including respiratory depression, produced by toxic doses of TCAs. With therapeutic doses of TCAs, barbiturates increase metabolism and decrease blood concentrations of TCAs.

• ondansetron

  pentobarbital will decrease the level or effect of ondansetron by affecting hepatic enzyme CYP1A2 metabolism. Minor/Significance Unknown.

• oxybutynin

  pentobarbital will decrease the level or effect of oxybutynin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• paclitaxel

  pentobarbital will decrease the level or effect of paclitaxel by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• paclitaxel protein bound

  pentobarbital will decrease the level or effect of paclitaxel protein bound by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• pantoprazole

  pentobarbital will decrease the level or effect of pantoprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• parecoxib

  pentobarbital will decrease the level or effect of parecoxib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• phenelzine

  phenelzine increases levels of pentobarbital by decreasing metabolism. Minor/Significance Unknown. Theoretical interaction.

• pimozide

  pentobarbital will decrease the level or effect of pimozide by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• pioglitazone

  pentobarbital will decrease the level or effect of pioglitazone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• piroxicam

  pentobarbital will decrease the level or effect of piroxicam by affecting hepatic enzyme CYP2C9/10 metabolism. Minor/Significance Unknown.

• posaconazole

  pentobarbital decreases levels of posaconazole by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.

• propafenone

  pentobarbital will decrease the level or effect of propafenone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• protriptyline

  pentobarbital, protriptyline. Other (see comment). Minor/Significance Unknown. Comment: Barbiturates may increase adverse effects, including respiratory depression, produced by toxic doses of TCAs. With therapeutic doses of TCAs, barbiturates increase metabolism and decrease blood concentrations of TCAs.

• quinine

  pentobarbital will decrease the level or effect of quinine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• rabeprazole

  pentobarbital will decrease the level or effect of rabeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• ramelteon

  pentobarbital will decrease the level or effect of ramelteon by affecting hepatic enzyme CYP2C9/10 metabolism. Minor/Significance Unknown.
  
  pentobarbital will decrease the level or effect of ramelteon by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• riluzole

  pentobarbital will decrease the level or effect of riluzole by affecting hepatic enzyme CYP1A2 metabolism. Minor/Significance Unknown.

• rose hips

  pentobarbital decreases levels of rose hips by increasing elimination. Minor/Significance Unknown.

• sage

  pentobarbital and sage both increase sedation. Minor/Significance Unknown.

• saxagliptin

  pentobarbital will decrease the level or effect of saxagliptin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• selegiline transdermal

  selegiline transdermal increases levels of pentobarbital by decreasing metabolism. Minor/Significance Unknown. Theoretical interaction.

• Siberian ginseng

  Siberian ginseng increases effects of pentobarbital by pharmacodynamic synergism. Minor/Significance Unknown. May enhance CNS depression.

• sufentanil

  pentobarbital will decrease the level or effect of sufentanil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• sulfamethoxazole

  pentobarbital will decrease the level or effect of sulfamethoxazole by affecting hepatic enzyme CYP2C9/10 metabolism. Minor/Significance Unknown.

• thioridazine

  thioridazine decreases levels of pentobarbital by unspecified interaction mechanism. Minor/Significance Unknown.

• thyroid desiccated

  pentobarbital decreases levels of thyroid desiccated by increasing metabolism. Minor/Significance Unknown.

• tibolone

  pentobarbital decreases levels of tibolone by increasing metabolism. Minor/Significance Unknown. Theoretical interaction.

• tolbutamide

  pentobarbital will decrease the level or effect of tolbutamide by affecting hepatic enzyme CYP2C9/10 metabolism. Minor/Significance Unknown.

• topiramate

  pentobarbital decreases levels of topiramate by increasing metabolism. Minor/Significance Unknown.

• tranylcypromine

  tranylcypromine increases levels of pentobarbital by decreasing metabolism. Minor/Significance Unknown. Theoretical interaction.

• trazodone

  pentobarbital, trazodone. Other (see comment). Minor/Significance Unknown. Comment: Barbiturates may increase adverse effects, including respiratory depression, produced by toxic doses of TCAs. With therapeutic doses of TCAs, barbiturates increase metabolism and decrease blood concentrations of TCAs.

• trimipramine

  pentobarbital, trimipramine. Other (see comment). Minor/Significance Unknown. Comment: Barbiturates may increase adverse effects, including respiratory depression, produced by toxic doses of TCAs. With therapeutic doses of TCAs, barbiturates increase metabolism and decrease blood concentrations of TCAs.

• vinblastine

  pentobarbital will decrease the level or effect of vinblastine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• vincristine

  pentobarbital will decrease the level or effect of vincristine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• vincristine liposomal

  pentobarbital will decrease the level or effect of vincristine liposomal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• vinorelbine

  pentobarbital will decrease the level or effect of vinorelbine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• voriconazole

  pentobarbital will decrease the level or effect of voriconazole by affecting hepatic enzyme CYP2C19 metabolism. Minor/Significance Unknown.
  
  pentobarbital will decrease the level or effect of voriconazole by affecting hepatic enzyme CYP2C9/10 metabolism. Minor/Significance Unknown.

• zaleplon

  pentobarbital will decrease the level or effect of zaleplon by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• ziprasidone

  pentobarbital will decrease the level or effect of ziprasidone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• zolpidem

  pentobarbital will decrease the level or effect of zolpidem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• zonisamide

  pentobarbital will decrease the level or effect of zonisamide by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• abemaciclib

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of abemaciclib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Coadministration of abemaciclib with strong CYP3A4 inducers reduces plasma concentration of abemaciclib and its metabolites.

• abiraterone

  Monitor Closely (1)pentobarbital will decrease the level or effect of abiraterone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• acalabrutinib

  Monitor Closely (1)pentobarbital will decrease the level or effect of acalabrutinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• acebutolol

  Monitor Closely (1)pentobarbital decreases levels of acebutolol by increasing metabolism. Use Caution/Monitor. Consider a higher beta-blocker dose during coadministration of pentobarbital. Atenolol, sotalol, nadolol less likely to be affected than other beta blockers.

• acetazolamide

  Minor (1)acetazolamide, pentobarbital. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Increased risk of anticonvulsant induced osteomalacia.

• acrivastine

  Monitor Closely (1)acrivastine and pentobarbital both increase sedation. Use Caution/Monitor.

• albuterol

  Monitor Closely (1)pentobarbital increases and albuterol decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• alfentanil

  Monitor Closely (1)pentobarbital and alfentanil both increase sedation. Use Caution/Monitor.Minor (1)pentobarbital will decrease the level or effect of alfentanil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• alfuzosin

  Minor (1)pentobarbital will decrease the level or effect of alfuzosin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• almotriptan

  Monitor Closely (1)pentobarbital will decrease the level or effect of almotriptan by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• alosetron

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of alosetron by affecting hepatic enzyme CYP1A2 metabolism. Avoid or Use Alternate Drug.Minor (2)pentobarbital will decrease the level or effect of alosetron by affecting hepatic enzyme CYP2C9/10 metabolism. Minor/Significance Unknown.
  
  pentobarbital will decrease the level or effect of alosetron by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• alpelisib

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of alpelisib by pharmacodynamic synergism. Avoid or Use Alternate Drug. Avoid coadministration of alpelisib (CYP3A4 substrate) with strong CYP3A4 inducers.

• alprazolam

  Monitor Closely (2)pentobarbital will decrease the level or effect of alprazolam by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
  
  pentobarbital and alprazolam both increase sedation. Use Caution/Monitor.

• ambrisentan

  Minor (1)pentobarbital will decrease the level or effect of ambrisentan by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• amifostine

  Monitor Closely (1)amifostine, pentobarbital. Either increases effects of the other by anti-hypertensive channel blocking. Use Caution/Monitor. Monitor hemodynamic changes, specifically for signs of hypotension, if using barbiturates with blood pressure lowering medications. .

• amiodarone

  Monitor Closely (1)pentobarbital will decrease the level or effect of amiodarone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• amisulpride

  Monitor Closely (1)amisulpride and pentobarbital both increase sedation. Use Caution/Monitor.

• amitriptyline

  Monitor Closely (3)pentobarbital will decrease the level or effect of amitriptyline by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.
  
  pentobarbital will decrease the level or effect of amitriptyline by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely.
  
  pentobarbital and amitriptyline both increase sedation. Use Caution/Monitor.Minor (1)pentobarbital, amitriptyline. Other (see comment). Minor/Significance Unknown. Comment: Barbiturates may increase adverse effects, including respiratory depression, produced by toxic doses of TCAs. With therapeutic doses of TCAs, barbiturates increase metabolism and decrease blood concentrations of TCAs.

• amlodipine

  Monitor Closely (1)pentobarbital will decrease the level or effect of amlodipine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• amobarbital

  Monitor Closely (1)amobarbital and pentobarbital both increase sedation. Use Caution/Monitor.

• amoxapine

  Monitor Closely (1)pentobarbital and amoxapine both increase sedation. Use Caution/Monitor.Minor (1)pentobarbital, amoxapine. Other (see comment). Minor/Significance Unknown. Comment: Barbiturates may increase adverse effects, including respiratory depression, produced by toxic doses of TCAs. With therapeutic doses of TCAs, barbiturates increase metabolism and decrease blood concentrations of TCAs.

• amphotericin B deoxycholate

  Minor (1)pentobarbital decreases levels of amphotericin B deoxycholate by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.

• antipyrine

  Minor (1)pentobarbital will decrease the level or effect of antipyrine by affecting hepatic enzyme CYP1A2 metabolism. Minor/Significance Unknown.

• antithrombin alfa

  Serious - Use Alternative (1)pentobarbital decreases effects of antithrombin alfa by increasing metabolism. Avoid or Use Alternate Drug.

• antithrombin III

  Serious - Use Alternative (1)pentobarbital decreases effects of antithrombin III by increasing metabolism. Avoid or Use Alternate Drug.

• apomorphine

  Monitor Closely (1)pentobarbital and apomorphine both increase sedation. Use Caution/Monitor.

• apremilast

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of apremilast by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Coadministration with strong CYP inducers results in a significant decrease of systemic exposure of apremilast, which may result in loss of efficacy

• aprepitant

  Monitor Closely (1)pentobarbital will decrease the level or effect of aprepitant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• arformoterol

  Monitor Closely (1)pentobarbital increases and arformoterol decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• argatroban

  Serious - Use Alternative (1)pentobarbital decreases effects of argatroban by increasing metabolism. Avoid or Use Alternate Drug.

• aripiprazole

  Monitor Closely (2)pentobarbital will decrease the level or effect of aripiprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
  
  pentobarbital and aripiprazole both increase sedation. Use Caution/Monitor.

• armodafinil

  Monitor Closely (1)pentobarbital increases and armodafinil decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.Minor (1)pentobarbital will decrease the level or effect of armodafinil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• artemether/lumefantrine

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of artemether/lumefantrine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Coadministration with strong CYP3A4 inducers can result in decreased serum concentrations and loss of antimalarial efficacy

• asenapine

  Monitor Closely (1)asenapine and pentobarbital both increase sedation. Use Caution/Monitor.Minor (1)pentobarbital will decrease the level or effect of asenapine by affecting hepatic enzyme CYP1A2 metabolism. Minor/Significance Unknown.

• asenapine transdermal

  Monitor Closely (1)asenapine transdermal and pentobarbital both increase sedation. Use Caution/Monitor.

• ashwagandha

  Minor (1)ashwagandha increases effects of pentobarbital by pharmacodynamic synergism. Minor/Significance Unknown. May enhance CNS depression.

• atazanavir

  Minor (1)pentobarbital will decrease the level or effect of atazanavir by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• atenolol

  Monitor Closely (1)pentobarbital decreases levels of atenolol by increasing metabolism. Use Caution/Monitor. Consider a higher beta-blocker dose during coadministration of pentobarbital. Atenolol, sotalol, nadolol less likely to be affected than other beta blockers.

• atogepant

  Monitor Closely (1)pentobarbital will decrease the level or effect of atogepant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Recommended atogepant dosage with concomitant use of strong or moderate CYP3A4 inducers is 30 mg or 60 mg qDay.

• atorvastatin

  Monitor Closely (1)pentobarbital will decrease the level or effect of atorvastatin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• avanafil

  Monitor Closely (1)pentobarbital will decrease the level or effect of avanafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. For patients with ED, monitor response carefully because of potential for decreased effectiveness.

• avapritinib

  Monitor Closely (1)avapritinib and pentobarbital both increase sedation. Use Caution/Monitor.Serious - Use Alternative (1)pentobarbital will decrease the level or effect of avapritinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• axitinib

  Serious - Use Alternative (1)pentobarbital decreases levels of axitinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Selection of concomitant medication with no or minimal CYP3A4 induction potential is recommended.

• azelastine

  Monitor Closely (1)azelastine and pentobarbital both increase sedation. Use Caution/Monitor.

• baclofen

  Monitor Closely (1)pentobarbital and baclofen both increase sedation. Use Caution/Monitor.

• bazedoxifene/conjugated estrogens

  Monitor Closely (1)pentobarbital will decrease the level or effect of bazedoxifene/conjugated estrogens by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• bedaquiline

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of bedaquiline by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of bedaquiline with strong CYP3A4 inducers due to potential for decreased therapeutic effect

• belladonna and opium

  Monitor Closely (1)pentobarbital and belladonna and opium both increase sedation. Use Caution/Monitor.

• belumosudil

  Monitor Closely (1)pentobarbital will decrease the level or effect of belumosudil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Increase belumosudil dosage to 200 mg PO BID when coadministered with strong CYP3A inducers.

• bemiparin

  Serious - Use Alternative (1)pentobarbital decreases effects of bemiparin by increasing metabolism. Avoid or Use Alternate Drug.

• benazepril

  Monitor Closely (1)pentobarbital, benazepril. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Enhanced hypotensive effects.

• bendamustine

  Monitor Closely (1)pentobarbital decreases levels of bendamustine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor. Concentrations of active metabolites may be increased.

• benperidol

  Monitor Closely (1)pentobarbital and benperidol both increase sedation. Use Caution/Monitor.

• benzhydrocodone/acetaminophen

  Monitor Closely (1)pentobarbital will decrease the level or effect of benzhydrocodone/acetaminophen by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Caution when discontinuing CYP3A4 inducers that are coadministered with benzhydrocodone (prodrug of hydrocodone); plasma concentrations of hydrocodone may increase and can result in potentially fatal respiratory depression.Serious - Use Alternative (2)benzhydrocodone/acetaminophen, pentobarbital. Either increases toxicity of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Profound sedation, respiratory depression, coma, and death may result if coadministered. Reserve concomitant prescribing of these drugs in patients for whom other treatment options are inadequate. Limit dosages and durations to the minimum required. Monitor closely for signs of respiratory depression and sedation.
  
  benzhydrocodone/acetaminophen and pentobarbital both increase sedation. Avoid or Use Alternate Drug. Limit use to patients for whom alternative treatment options are inadequate

• benzphetamine

  Monitor Closely (1)pentobarbital increases and benzphetamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• betaxolol

  Monitor Closely (1)pentobarbital decreases levels of betaxolol by increasing metabolism. Use Caution/Monitor. Consider a higher beta-blocker dose during coadministration of pentobarbital. Atenolol, sotalol, nadolol less likely to be affected than other beta blockers.

• bexarotene

  Monitor Closely (1)pentobarbital will decrease the level or effect of bexarotene by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• bisoprolol

  Monitor Closely (1)pentobarbital decreases levels of bisoprolol by increasing metabolism. Use Caution/Monitor. Consider a higher beta-blocker dose during coadministration of pentobarbital. Atenolol, sotalol, nadolol less likely to be affected than other beta blockers.

• bivalirudin

  Serious - Use Alternative (1)pentobarbital decreases effects of bivalirudin by increasing metabolism. Avoid or Use Alternate Drug.

• bortezomib

  Monitor Closely (1)pentobarbital will decrease the level or effect of bortezomib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• bosentan

  Minor (2)pentobarbital will decrease the level or effect of bosentan by affecting hepatic enzyme CYP2C9/10 metabolism. Minor/Significance Unknown.
  
  pentobarbital will decrease the level or effect of bosentan by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• bosutinib

  Serious - Use Alternative (1)pentobarbital decreases levels of bosutinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Strong CYP3A4 inducers decreased bosutinib plasma concentration by ~85%.

• brexanolone

  Monitor Closely (1)brexanolone, pentobarbital. Either increases toxicity of the other by sedation. Use Caution/Monitor.

• brexpiprazole

  Monitor Closely (2)pentobarbital will decrease the level or effect of brexpiprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Double brexpiprazole dose over 1-2 weeks if administered with a strong CYP3A4 inducer.
  
  brexpiprazole and pentobarbital both increase sedation. Use Caution/Monitor.

• brigatinib

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of brigatinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Coadministration with strong CYP3A4 inducers may decrease brigatinib efficacy.

• brimonidine

  Monitor Closely (1)brimonidine and pentobarbital both increase sedation. Use Caution/Monitor.Minor (1)brimonidine increases effects of pentobarbital by pharmacodynamic synergism. Minor/Significance Unknown. Increased CNS depression.

• brinzolamide

  Minor (1)brinzolamide, pentobarbital. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Increased risk of anticonvulsant induced osteomalacia.

• brivaracetam

  Monitor Closely (1)brivaracetam and pentobarbital both increase sedation. Use Caution/Monitor.

• brompheniramine

  Monitor Closely (1)brompheniramine and pentobarbital both increase sedation. Use Caution/Monitor.

• budesonide

  Monitor Closely (1)pentobarbital will decrease the level or effect of budesonide by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• bupivacaine implant

  Monitor Closely (1)pentobarbital, bupivacaine implant. Either increases toxicity of the other by Other (see comment). Use Caution/Monitor. Comment: Local anesthetics may increase the risk of developing methemoglobinemia when concurrently exposed to drugs that also cause methemoglobinemia.

• buprenorphine

  Monitor Closely (2)pentobarbital will decrease the level or effect of buprenorphine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
  
  pentobarbital and buprenorphine both increase sedation. Use Caution/Monitor.

• buprenorphine buccal

  Monitor Closely (2)pentobarbital will decrease the level or effect of buprenorphine buccal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
  
  pentobarbital and buprenorphine buccal both increase sedation. Use Caution/Monitor.

• buprenorphine subdermal implant

  Monitor Closely (1)pentobarbital will decrease the level or effect of buprenorphine subdermal implant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Monitor patients already on buprenorphine subdermal implant who require newly-initiated treatment with CYP3A4 inducer for signs and symptoms of withdrawal. If the dose of the concomitant CYP3A4 inducer cannot be reduced or discontinued, implant removal may be necessary and the patient should then be treated with a buprenorphine dosage form that permits dose adjustments. If a CYP3A4 inducer is discontinued in a patient who has been stabilized on buprenorphine, monitor the patient for overmedication.Serious - Use Alternative (1)buprenorphine subdermal implant and pentobarbital both increase sedation. Avoid or Use Alternate Drug. Limit use to patients for whom alternative treatment options are inadequate

• buprenorphine transdermal

  Serious - Use Alternative (1)buprenorphine transdermal and pentobarbital both increase sedation. Avoid or Use Alternate Drug. Limit use to patients for whom alternative treatment options are inadequate

• buprenorphine, long-acting injection

  Monitor Closely (2)pentobarbital will decrease the level or effect of buprenorphine, long-acting injection by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Patients who transfer to buprenorphine long-acting injection from transmucosal buprenorphine coadministered with CYP3A4 inducers should be monitored to ensure buprenorphine plasma levels are adequate. If the buprenorphine dose is inadequate and the CYP3A4 inducer cannot be reduced or discontinued, transition the patient back to a buprenorphine formulation that permits dose adjustments.
  
  pentobarbital increases toxicity of buprenorphine, long-acting injection by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of buprenorphine and benzodiazepines or other CNS depressants increases risk of adverse reactions including overdose, respiratory depression, and death. Cessation of benzodiazepines or other CNS depressants is preferred in most cases. In some cases, monitoring at a higher level of care for tapering CNS depressants may be appropriate. In others, gradually tapering a patient off of a prescribed benzodiazepine or other CNS depressant or decreasing to the lowest effective dose may be appropriate.

• bupropion

  Monitor Closely (1)pentobarbital, bupropion. increasing metabolism. Use Caution/Monitor. Decr levels of bupropion, but incr levels of active metabolites. .

• buspirone

  Monitor Closely (1)pentobarbital will decrease the level or effect of buspirone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• butabarbital

  Monitor Closely (1)butabarbital and pentobarbital both increase sedation. Use Caution/Monitor.

• butalbital

  Monitor Closely (1)butalbital and pentobarbital both increase sedation. Use Caution/Monitor.

• butorphanol

  Monitor Closely (1)pentobarbital and butorphanol both increase sedation. Use Caution/Monitor.

• cabazitaxel

  Monitor Closely (1)pentobarbital will decrease the level or effect of cabazitaxel by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Coadministration of strong CYP3A4 inducers may decrease cabazitaxel concentrations. Avoid coadministration.

• cabozantinib

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of cabozantinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of cabozantinib with strong CYP3A4 inducers. If a strong CYP3A4 inducer is required, increase cabozantinib dose by 40 mg/day (Cometriq) or by 20 mg/day (Cabometyx). Resume previous dose 2-3 days after strong CYP3A4 inducer discontinued.

• caffeine

  Monitor Closely (1)pentobarbital increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.Minor (1)pentobarbital will decrease the level or effect of caffeine by affecting hepatic enzyme CYP1A2 metabolism. Minor/Significance Unknown.

• calcifediol

  Monitor Closely (1)pentobarbital, calcifediol. affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Drugs that stimulate microsomal hydroxylation reduce the half-life of calcifediol.

• calcium/magnesium/potassium/sodium oxybates

  Serious - Use Alternative (1)pentobarbital, calcium/magnesium/potassium/sodium oxybates. Either increases effects of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Profound sedation, respiratory depression, coma, and death may result if coadministered. Reserve concomitant prescribing of these drugs in patients for whom other treatment options are inadequate. Limit dosages and durations to the minimum required. Monitor closely for signs of respiratory depression and sedation.

• cannabidiol

  Monitor Closely (1)pentobarbital will decrease the level or effect of cannabidiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Consider an increase in cannabidiol dosage (based on clinical response and tolerability) when coadministered with a strong CYP3A4 inducer.

• captopril

  Monitor Closely (1)pentobarbital, captopril. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Both drugs lower blood pressure. Monitor blood pressure.

• carbamazepine

  Monitor Closely (1)pentobarbital will decrease the level or effect of carbamazepine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• carbinoxamine

  Monitor Closely (1)carbinoxamine and pentobarbital both increase sedation. Use Caution/Monitor.

• cariprazine

  Contraindicated (1)pentobarbital will decrease the level or effect of cariprazine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated. CYP3A4 is responsible for the formation and elimination of cariprazine's active metabolites. The effect of CYP3A4 inducers on cariprazine exposure has not been evaluated and the net effect is unclear.

• carisoprodol

  Monitor Closely (1)pentobarbital and carisoprodol both increase sedation. Use Caution/Monitor.

• carvedilol

  Monitor Closely (2)pentobarbital will decrease the level or effect of carvedilol by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.
  
  pentobarbital decreases levels of carvedilol by increasing metabolism. Use Caution/Monitor. Consider a higher beta-blocker dose during coadministration of pentobarbital. Atenolol, sotalol, nadolol less likely to be affected than other beta blockers.

• celecoxib

  Minor (1)pentobarbital will decrease the level or effect of celecoxib by affecting hepatic enzyme CYP2C9/10 metabolism. Minor/Significance Unknown.

• celiprolol

  Monitor Closely (1)pentobarbital decreases levels of celiprolol by increasing metabolism. Use Caution/Monitor. Atenolol, sotalol, nadolol less likely to be affected than other beta blockers.

• cenobamate

  Monitor Closely (1)cenobamate, pentobarbital. Either increases effects of the other by sedation. Use Caution/Monitor.

• ceritinib

  Serious - Use Alternative (1)pentobarbital decreases levels of ceritinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• cevimeline

  Minor (1)pentobarbital will decrease the level or effect of cevimeline by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• chloral hydrate

  Monitor Closely (1)pentobarbital and chloral hydrate both increase sedation. Use Caution/Monitor.

• chloramphenicol

  Monitor Closely (1)chloramphenicol increases levels of pentobarbital by decreasing metabolism. Use Caution/Monitor.Minor (1)pentobarbital decreases levels of chloramphenicol by increasing metabolism. Minor/Significance Unknown.

• chlordiazepoxide

  Monitor Closely (1)pentobarbital and chlordiazepoxide both increase sedation. Use Caution/Monitor.

• chlorpheniramine

  Monitor Closely (1)chlorpheniramine and pentobarbital both increase sedation. Use Caution/Monitor.

• chlorpromazine

  Monitor Closely (1)pentobarbital and chlorpromazine both increase sedation. Use Caution/Monitor.Minor (1)pentobarbital decreases levels of chlorpromazine by increasing metabolism. Minor/Significance Unknown.

• chlorzoxazone

  Monitor Closely (1)pentobarbital and chlorzoxazone both increase sedation. Use Caution/Monitor.

• cilostazol

  Monitor Closely (1)pentobarbital will decrease the level or effect of cilostazol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• cimetidine

  Minor (1)pentobarbital will decrease the level or effect of cimetidine by affecting hepatic enzyme CYP2C19 metabolism. Minor/Significance Unknown.

• cinacalcet

  Monitor Closely (1)pentobarbital will decrease the level or effect of cinacalcet by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• cinnarizine

  Monitor Closely (1)cinnarizine and pentobarbital both increase sedation. Use Caution/Monitor.

• clarithromycin

  Minor (2)pentobarbital will decrease the level or effect of clarithromycin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.
  
  pentobarbital decreases levels of clarithromycin by increasing elimination. Minor/Significance Unknown.

• clemastine

  Monitor Closely (1)clemastine and pentobarbital both increase sedation. Use Caution/Monitor.

• clobazam

  Monitor Closely (1)pentobarbital, clobazam. Other (see comment). Use Caution/Monitor. Comment: Concomitant administration can increase the potential for CNS effects (e.g., increased sedation or respiratory depression).

• clomipramine

  Monitor Closely (3)pentobarbital will decrease the level or effect of clomipramine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.
  
  pentobarbital will decrease the level or effect of clomipramine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely.
  
  pentobarbital and clomipramine both increase sedation. Use Caution/Monitor.Minor (1)pentobarbital, clomipramine. Other (see comment). Minor/Significance Unknown. Comment: Barbiturates may increase adverse effects, including respiratory depression, produced by toxic doses of TCAs. With therapeutic doses of TCAs, barbiturates increase metabolism and decrease blood concentrations of TCAs.

• clonazepam

  Monitor Closely (1)pentobarbital and clonazepam both increase sedation. Use Caution/Monitor.

• clopidogrel

  Monitor Closely (1)pentobarbital will increase the level or effect of clopidogrel by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. CYP3A4 inducers may increase the metabolism of clopidogrel to its active metabolite. Monitor patients for potential increase in antiplatelet effects when CYP3A4 inducers are used in combination with clopidogrel

• clorazepate

  Monitor Closely (1)pentobarbital and clorazepate both increase sedation. Use Caution/Monitor.

• clotrimazole

  Minor (1)pentobarbital decreases levels of clotrimazole by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.

• clozapine

  Monitor Closely (3)pentobarbital will decrease the level or effect of clozapine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.
  
  pentobarbital will decrease the level or effect of clozapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
  
  pentobarbital and clozapine both increase sedation. Use Caution/Monitor.

• cobimetinib

  Contraindicated (1)pentobarbital will decrease the level or effect of cobimetinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated. Avoid coadministration. Strong or moderate CYP3A inducers may decrease cobimetinib systemic exposure by >80% and reduce its efficacy.

• cocaine topical

  Minor (1)pentobarbital will decrease the level or effect of cocaine topical by affecting hepatic enzyme CYP2B6 metabolism. Minor/Significance Unknown.

• codeine

  Monitor Closely (1)pentobarbital and codeine both increase sedation. Use Caution/Monitor.

• colchicine

  Monitor Closely (1)pentobarbital will decrease the level or effect of colchicine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• conivaptan

  Monitor Closely (1)pentobarbital will decrease the level or effect of conivaptan by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• conjugated estrogens

  Monitor Closely (1)pentobarbital will decrease the level or effect of conjugated estrogens by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• conjugated estrogens, vaginal

  Monitor Closely (1)pentobarbital will decrease the level or effect of conjugated estrogens, vaginal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• copanlisib

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of copanlisib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of copanlisib with strong CYP3A4 inducers.

• cortisone

  Monitor Closely (1)pentobarbital will decrease the level or effect of cortisone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• cyclizine

  Monitor Closely (1)cyclizine and pentobarbital both increase sedation. Use Caution/Monitor.

• cyclobenzaprine

  Monitor Closely (1)pentobarbital and cyclobenzaprine both increase sedation. Use Caution/Monitor.

• cyclophosphamide

  Monitor Closely (1)pentobarbital will decrease the level or effect of cyclophosphamide by affecting hepatic enzyme CYP2B6 metabolism. Use Caution/Monitor.

• cyclosporine

  Monitor Closely (1)pentobarbital will decrease the level or effect of cyclosporine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• cyproheptadine

  Monitor Closely (1)cyproheptadine and pentobarbital both increase sedation. Use Caution/Monitor.

• dabrafenib

  Serious - Use Alternative (1)pentobarbital decreases levels of dabrafenib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• dalteparin

  Serious - Use Alternative (1)pentobarbital decreases effects of dalteparin by increasing metabolism. Avoid or Use Alternate Drug.

• dantrolene

  Monitor Closely (1)pentobarbital and dantrolene both increase sedation. Use Caution/Monitor.

• dapsone

  Minor (1)pentobarbital will decrease the level or effect of dapsone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• daridorexant

  Monitor Closely (1)pentobarbital and daridorexant both increase sedation. Modify Therapy/Monitor Closely. Coadministration increases risk of CNS depression, which can lead to additive impairment of psychomotor performance and cause daytime impairment. Serious - Use Alternative (1)pentobarbital will decrease the level or effect of daridorexant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• darifenacin

  Monitor Closely (1)pentobarbital will decrease the level or effect of darifenacin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• darunavir

  Monitor Closely (1)pentobarbital will decrease the level or effect of darunavir by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• dasatinib

  Monitor Closely (1)pentobarbital will decrease the level or effect of dasatinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• deflazacort

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of deflazacort by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of deflazacort with moderate or strong CYP3A4 inducers.

• desipramine

  Monitor Closely (1)pentobarbital and desipramine both increase sedation. Use Caution/Monitor.Minor (1)pentobarbital, desipramine. Other (see comment). Minor/Significance Unknown. Comment: Barbiturates may increase adverse effects, including respiratory depression, produced by toxic doses of TCAs. With therapeutic doses of TCAs, barbiturates increase metabolism and decrease blood concentrations of TCAs.

• deutetrabenazine

  Monitor Closely (1)pentobarbital and deutetrabenazine both increase sedation. Use Caution/Monitor.

• dexamethasone

  Monitor Closely (1)pentobarbital will decrease the level or effect of dexamethasone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• dexchlorpheniramine

  Monitor Closely (1)dexchlorpheniramine and pentobarbital both increase sedation. Use Caution/Monitor.

• dexfenfluramine

  Monitor Closely (1)pentobarbital increases and dexfenfluramine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• dexmedetomidine

  Monitor Closely (1)pentobarbital and dexmedetomidine both increase sedation. Use Caution/Monitor.

• dexmethylphenidate

  Monitor Closely (1)pentobarbital increases and dexmethylphenidate decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• dextroamphetamine

  Monitor Closely (1)pentobarbital increases and dextroamphetamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• dextromoramide

  Monitor Closely (1)pentobarbital and dextromoramide both increase sedation. Use Caution/Monitor.

• diamorphine

  Monitor Closely (1)pentobarbital and diamorphine both increase sedation. Use Caution/Monitor.

• diazepam

  Monitor Closely (2)pentobarbital will decrease the level or effect of diazepam by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
  
  pentobarbital and diazepam both increase sedation. Use Caution/Monitor.

• diazepam intranasal

  Monitor Closely (2)pentobarbital will decrease the level or effect of diazepam intranasal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Strong or moderate CYP3A4 inducers may increase rate of diazepam elimination; therefore, efficacy of diazepam may be decreased.
  
  diazepam intranasal, pentobarbital. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Coadministration may potentiate the CNS-depressant effects of each drug.

• diclofenac

  Minor (1)pentobarbital will decrease the level or effect of diclofenac by affecting hepatic enzyme CYP2C9/10 metabolism. Minor/Significance Unknown.

• dienogest/estradiol valerate

  Contraindicated (1)pentobarbital will decrease the level or effect of dienogest/estradiol valerate by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated. Women should not choose estradiol valerate/dienogest as their contraceptive while using strong CYP3A4 inducers due to potential decrease in contraceptive efficacy. Estradiol valerate/dienogest should not be used for at least 28 days after discontinuation of the inducer due to possibility of decreased contraceptive efficacy.

• diethylpropion

  Monitor Closely (1)pentobarbital increases and diethylpropion decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• difelikefalin

  Monitor Closely (1)difelikefalin and pentobarbital both increase sedation. Use Caution/Monitor.

• difenoxin hcl

  Monitor Closely (1)pentobarbital and difenoxin hcl both increase sedation. Use Caution/Monitor.

• dihydroergotamine

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of dihydroergotamine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• dihydroergotamine intranasal

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of dihydroergotamine intranasal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• diltiazem

  Monitor Closely (1)pentobarbital will decrease the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• dimenhydrinate

  Monitor Closely (1)dimenhydrinate and pentobarbital both increase sedation. Use Caution/Monitor.

• diphenhydramine

  Monitor Closely (1)diphenhydramine and pentobarbital both increase sedation. Use Caution/Monitor.

• diphenoxylate hcl

  Monitor Closely (1)pentobarbital and diphenoxylate hcl both increase sedation. Use Caution/Monitor.

• dipipanone

  Monitor Closely (1)pentobarbital and dipipanone both increase sedation. Use Caution/Monitor.

• disopyramide

  Minor (1)pentobarbital will decrease the level or effect of disopyramide by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• dobutamine

  Monitor Closely (1)pentobarbital increases and dobutamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• docetaxel

  Minor (1)pentobarbital will decrease the level or effect of docetaxel by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• donepezil

  Minor (1)pentobarbital will decrease the level or effect of donepezil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• dopamine

  Monitor Closely (1)pentobarbital increases and dopamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• dopexamine

  Monitor Closely (1)pentobarbital increases and dopexamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• doravirine

  Contraindicated (1)pentobarbital will decrease the level or effect of doravirine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated. Coadministration of doravirine with a strong CYP3A inducer may decrease doravirine plasma concentrations and/or effects. Potential for loss of virologic response and possible resistance to doravirine.

• dosulepin

  Monitor Closely (1)pentobarbital and dosulepin both increase sedation. Use Caution/Monitor.Minor (1)pentobarbital, dosulepin. Other (see comment). Minor/Significance Unknown. Comment: Barbiturates may increase adverse effects, including respiratory depression, produced by toxic doses of TCAs. With therapeutic doses of TCAs, barbiturates increase metabolism and decrease blood concentrations of TCAs.

• doxepin

  Monitor Closely (1)pentobarbital and doxepin both increase sedation. Use Caution/Monitor.Minor (1)pentobarbital, doxepin. Other (see comment). Minor/Significance Unknown. Comment: Barbiturates may increase adverse effects, including respiratory depression, produced by toxic doses of TCAs. With therapeutic doses of TCAs, barbiturates increase metabolism and decrease blood concentrations of TCAs.

• doxorubicin

  Monitor Closely (1)pentobarbital will decrease the level or effect of doxorubicin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• doxorubicin liposomal

  Monitor Closely (1)pentobarbital will decrease the level or effect of doxorubicin liposomal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• doxycycline

  Monitor Closely (1)pentobarbital decreases levels of doxycycline by increasing metabolism. Use Caution/Monitor.

• doxylamine

  Monitor Closely (1)pentobarbital and doxylamine both increase sedation. Use Caution/Monitor.

• dronabinol

  Monitor Closely (1)pentobarbital will decrease the level or effect of dronabinol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Dronabinol is a CYP3A4 substrate.

• dronedarone

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of dronedarone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• droperidol

  Monitor Closely (1)pentobarbital and droperidol both increase sedation. Use Caution/Monitor.

• duloxetine

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of duloxetine by affecting hepatic enzyme CYP1A2 metabolism. Avoid or Use Alternate Drug.

• dutasteride

  Minor (1)pentobarbital will decrease the level or effect of dutasteride by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• duvelisib

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of duvelisib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Coadministration with a strong CYP3A inducer decreases duvelisib area under the curve (AUC), which may reduce duvelisib efficacy.

• efavirenz

  Minor (1)pentobarbital will decrease the level or effect of efavirenz by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• elacestrant

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of elacestrant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• elagolix

  Monitor Closely (1)pentobarbital will decrease the level or effect of elagolix by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• elbasvir/grazoprevir

  Contraindicated (1)pentobarbital will decrease the level or effect of elbasvir/grazoprevir by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated. The therapeutic effect of elbasvir/grazoprevir may be reduced if coadministered with strong CYP3A inducers and is therefore contraindicated.

• eletriptan

  Monitor Closely (1)pentobarbital will decrease the level or effect of eletriptan by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• eliglustat

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of eliglustat by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Strong CYP3A inducers significantly decreases eliglustat exposure; coadministration not recommended

• eltrombopag

  Monitor Closely (2)pentobarbital will decrease the level or effect of eltrombopag by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.
  
  pentobarbital will decrease the level or effect of eltrombopag by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.

• elvitegravir

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of elvitegravir by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid; coadministration with CYP3A inducers may result in decreased plasma concentrations of elvitegravir and/or a concomitantly administered protease inhibitor and lead to loss of therapeutic effect and to possible resistance

• elvitegravir/cobicistat/emtricitabine/tenofovir DF

  Contraindicated (1)pentobarbital decreases levels of elvitegravir/cobicistat/emtricitabine/tenofovir DF by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated. May lead to loss of virologic response and possible resistance.

• enoxaparin

  Serious - Use Alternative (1)pentobarbital decreases effects of enoxaparin by increasing metabolism. Avoid or Use Alternate Drug.

• ephedrine

  Monitor Closely (1)pentobarbital increases and ephedrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• epinephrine

  Monitor Closely (1)pentobarbital increases and epinephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• epinephrine racemic

  Monitor Closely (1)pentobarbital increases and epinephrine racemic decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• eplerenone

  Minor (1)pentobarbital will decrease the level or effect of eplerenone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• erdafitinib

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of erdafitinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• ergotamine

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of ergotamine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• erlotinib

  Monitor Closely (1)pentobarbital will decrease the level or effect of erlotinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• erythromycin base

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of erythromycin base by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.Minor (1)pentobarbital decreases levels of erythromycin base by increasing elimination. Minor/Significance Unknown.

• erythromycin ethylsuccinate

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of erythromycin ethylsuccinate by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.Minor (1)pentobarbital decreases levels of erythromycin ethylsuccinate by increasing elimination. Minor/Significance Unknown.

• erythromycin lactobionate

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of erythromycin lactobionate by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.Minor (1)pentobarbital decreases levels of erythromycin lactobionate by increasing elimination. Minor/Significance Unknown.

• erythromycin stearate

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of erythromycin stearate by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.Minor (1)pentobarbital decreases levels of erythromycin stearate by increasing elimination. Minor/Significance Unknown.

• escitalopram

  Monitor Closely (1)pentobarbital will decrease the level or effect of escitalopram by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.

• esketamine intranasal

  Monitor Closely (1)esketamine intranasal, pentobarbital. Either increases toxicity of the other by sedation. Modify Therapy/Monitor Closely.

• esmolol

  Monitor Closely (1)pentobarbital decreases levels of esmolol by increasing metabolism. Use Caution/Monitor. Consider a higher beta-blocker dose during coadministration of pentobarbital. Atenolol, sotalol, nadolol less likely to be affected than other beta blockers.

• esomeprazole

  Monitor Closely (1)pentobarbital will decrease the level or effect of esomeprazole by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.

• estazolam

  Monitor Closely (1)pentobarbital and estazolam both increase sedation. Use Caution/Monitor.

• estradiol

  Monitor Closely (1)pentobarbital will decrease the level or effect of estradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• estradiol vaginal

  Monitor Closely (1)pentobarbital will decrease the level or effect of estradiol vaginal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• estrogens conjugated synthetic

  Monitor Closely (1)pentobarbital will decrease the level or effect of estrogens conjugated synthetic by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• estrogens esterified

  Monitor Closely (1)pentobarbital will decrease the level or effect of estrogens esterified by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• estropipate

  Monitor Closely (1)pentobarbital will decrease the level or effect of estropipate by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• ethanol

  Monitor Closely (1)pentobarbital and ethanol both increase sedation. Use Caution/Monitor.

• ethinylestradiol

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of ethinylestradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. The efficacy of hormonal contraceptives may be reduced. Use of a nonhormonal contraceptive is recommended.

• ethosuximide

  Minor (1)ethosuximide decreases effects of pentobarbital by pharmacodynamic antagonism. Minor/Significance Unknown.

• ethotoin

  Monitor Closely (1)pentobarbital will decrease the level or effect of ethotoin by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.

• etomidate

  Monitor Closely (1)etomidate and pentobarbital both increase sedation. Use Caution/Monitor.

• etonogestrel

  Monitor Closely (1)pentobarbital will decrease the level or effect of etonogestrel by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• etoposide

  Monitor Closely (1)pentobarbital will decrease the level or effect of etoposide by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• etravirine

  Monitor Closely (3)pentobarbital will decrease the level or effect of etravirine by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.
  
  pentobarbital will decrease the level or effect of etravirine by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.
  
  pentobarbital will decrease the level or effect of etravirine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• eucalyptus

  Minor (2)pentobarbital will decrease the level or effect of eucalyptus by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.
  
  pentobarbital and eucalyptus both increase sedation. Minor/Significance Unknown.

• everolimus

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of everolimus by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• exemestane

  Monitor Closely (1)pentobarbital will decrease the level or effect of exemestane by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. For patients receiving exemestane with a potent CYP3A4 inducer the recommended dose of exemestane is 50 mg daily after a meal.

• fedratinib

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of fedratinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Effect of coadministering a strong CYP3A4 inducer with fedratinib has not been studied.

• felodipine

  Monitor Closely (1)pentobarbital will decrease the level or effect of felodipine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• fenfluramine

  Monitor Closely (1)pentobarbital increases and fenfluramine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• fentanyl

  Monitor Closely (1)pentobarbital will decrease the level or effect of fentanyl by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Coadministration of fentanyl with CYP3A4 inducers could lead to a decrease in fentanyl plasma concentrations, lack of efficacy or, possibly, development of a withdrawal syndrome in a patient who has developed physical dependence to fentanyl. After stopping a CYP3A4 inducer, as the effects of the inducer decline, the fentanyl plasma concentration will increase which could increase or prolong both the therapeutic and adverse effects.Serious - Use Alternative (1)fentanyl, pentobarbital. Either increases effects of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Coadministration with other CNS depressants, such as skeletal muscle relaxants, may cause respiratory depression, hypotension, profound sedation, coma, and/or death. Consider dose reduction of either or both agents to avoid serious adverse effects. Monitor for hypotension, respiratory depression, and profound sedation.

• fentanyl intranasal

  Monitor Closely (1)pentobarbital will decrease the level or effect of fentanyl intranasal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Coadministration of fentanyl with CYP3A4 inducers could lead to a decrease in fentanyl plasma concentrations, lack of efficacy or, possibly, development of a withdrawal syndrome in a patient who has developed physical dependence to fentanyl. After stopping a CYP3A4 inducer, as the effects of the inducer decline, the fentanyl plasma concentration will increase which could increase or prolong both the therapeutic and adverse effects.Serious - Use Alternative (1)fentanyl intranasal, pentobarbital. Either increases effects of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Coadministration with other CNS depressants, such as skeletal muscle relaxants, may cause respiratory depression, hypotension, profound sedation, coma, and/or death. Consider dose reduction of either or both agents to avoid serious adverse effects. Monitor for hypotension, respiratory depression, and profound sedation.

• fentanyl transdermal

  Monitor Closely (1)pentobarbital will decrease the level or effect of fentanyl transdermal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Coadministration of fentanyl with CYP3A4 inducers could lead to a decrease in fentanyl plasma concentrations, lack of efficacy or, possibly, development of a withdrawal syndrome in a patient who has developed physical dependence to fentanyl. After stopping a CYP3A4 inducer, as the effects of the inducer decline, the fentanyl plasma concentration will increase which could increase or prolong both the therapeutic and adverse effects.Serious - Use Alternative (1)fentanyl transdermal, pentobarbital. Either increases effects of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Coadministration with other CNS depressants, such as skeletal muscle relaxants, may cause respiratory depression, hypotension, profound sedation, coma, and/or death. Consider dose reduction of either or both agents to avoid serious adverse effects. Monitor for hypotension, respiratory depression, and profound sedation.

• fentanyl transmucosal

  Monitor Closely (1)pentobarbital will decrease the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Coadministration of fentanyl with CYP3A4 inducers could lead to a decrease in fentanyl plasma concentrations, lack of efficacy or, possibly, development of a withdrawal syndrome in a patient who has developed physical dependence to fentanyl. After stopping a CYP3A4 inducer, as the effects of the inducer decline, the fentanyl plasma concentration will increase which could increase or prolong both the therapeutic and adverse effects.Serious - Use Alternative (1)fentanyl transmucosal, pentobarbital. Either increases effects of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Coadministration with other CNS depressants, such as skeletal muscle relaxants, may cause respiratory depression, hypotension, profound sedation, coma, and/or death. Consider dose reduction of either or both agents to avoid serious adverse effects. Monitor for hypotension, respiratory depression, and profound sedation.

• fesoterodine

  Monitor Closely (1)pentobarbital will decrease the level or effect of fesoterodine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• fexinidazole

  Serious - Use Alternative (1)pentobarbital will increase the level or effect of fexinidazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. CYP450 inducers may significantly increase plasma concentrations of fexinidazole?s active metabolites: fexinidazole sulfoxide (M1) and fexinidazole sulfone (M2). M2 plasma concentrations associated with increased QT prolongation risks.

• finasteride

  Minor (1)pentobarbital will decrease the level or effect of finasteride by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• finerenone

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of finerenone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• flibanserin

  Monitor Closely (2)pentobarbital will decrease the level or effect of flibanserin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Strong CYP3A4 inducers substantially decrease flibanserin systemic exposure.
  
  pentobarbital and flibanserin both increase sedation. Modify Therapy/Monitor Closely. Risk for sedation increased if flibanserin is coadministration with other CNS depressants.

• fluconazole

  Minor (1)pentobarbital decreases levels of fluconazole by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.

• fludrocortisone

  Monitor Closely (1)pentobarbital will decrease the level or effect of fludrocortisone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• fluphenazine

  Monitor Closely (1)pentobarbital and fluphenazine both increase sedation. Use Caution/Monitor.

• flurazepam

  Monitor Closely (1)pentobarbital and flurazepam both increase sedation. Use Caution/Monitor.

• flurbiprofen

  Minor (1)pentobarbital will decrease the level or effect of flurbiprofen by affecting hepatic enzyme CYP2C9/10 metabolism. Minor/Significance Unknown.

• fondaparinux

  Serious - Use Alternative (1)pentobarbital decreases effects of fondaparinux by increasing metabolism. Avoid or Use Alternate Drug.

• formoterol

  Monitor Closely (1)pentobarbital increases and formoterol decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• fosamprenavir

  Monitor Closely (1)pentobarbital will decrease the level or effect of fosamprenavir by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• fosaprepitant

  Monitor Closely (1)pentobarbital will decrease the level or effect of fosaprepitant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• fosphenytoin

  Monitor Closely (1)pentobarbital will decrease the level or effect of fosphenytoin by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.

• fostamatinib

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of fostamatinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• fostemsavir

  Contraindicated (1)pentobarbital will decrease the level or effect of fostemsavir by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated. Coadministration of fostemsavir (prodrug) with strong CYP3A4 inducers significantly decreases temsavir (active moiety) plasma concentrations, which may lead to loss of virologic response and resistance.

• frovatriptan

  Minor (1)pentobarbital will decrease the level or effect of frovatriptan by affecting hepatic enzyme CYP1A2 metabolism. Minor/Significance Unknown.

• gabapentin

  Monitor Closely (1)gabapentin, pentobarbital. Either increases effects of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of CNS depressants can result in serious, life-threatening, and fatal respiratory depression. Use lowest dose possible and monitor for respiratory depression and sedation.

• gabapentin enacarbil

  Monitor Closely (1)gabapentin enacarbil, pentobarbital. Either increases effects of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of CNS depressants can result in serious, life-threatening, and fatal respiratory depression. Use lowest dose possible and monitor for respiratory depression and sedation.

• galantamine

  Minor (1)pentobarbital will decrease the level or effect of galantamine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• ganaxolone

  Monitor Closely (1)pentobarbital and ganaxolone both increase sedation. Use Caution/Monitor.Serious - Use Alternative (1)pentobarbital will decrease the level or effect of ganaxolone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of ganaxolone with moderate or strong CYP3A4 inducers. If coadministration unavoidable, consider increasing ganaxolone dose; however, do not exceed maximum daily dose for weight.

• gefitinib

  Monitor Closely (1)pentobarbital will decrease the level or effect of gefitinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Increase gefitinib to 500 mg daily if coadministered with a strong CYP3A4 inducer. Resume gefitinib dose at 250 mg/day 7 days after discontinuing the strong inducer.

• glasdegib

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of glasdegib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of glasdegib with strong CYP3A inducers.

• glecaprevir/pibrentasvir

  Monitor Closely (1)pentobarbital will decrease the level or effect of glecaprevir/pibrentasvir by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Coadministration of drugs that induce CYP3A4 with glecaprevir/pibrentasvir may decrease glecaprevir/pibrentasvir plasma concentrations. Potential for loss of therapeutic effect.

• gotu kola

  Monitor Closely (1)gotu kola increases effects of pentobarbital by pharmacodynamic synergism. Use Caution/Monitor. May enhance CNS depression.

• griseofulvin

  Minor (1)pentobarbital decreases levels of griseofulvin by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.

• guanfacine

  Monitor Closely (1)pentobarbital will decrease the level or effect of guanfacine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Strong or moderate CYP3A4 inducers significantly reduce guanfacine plasma concentrations and elimination half-life. If coadministered, more frequent dosing of the IR product may be required to achieve or maintain the desired hypotensive response. For patients with ADHD, FDA-approved labeling for ER guanfacine recommends that, if coadministered, doubling the recommended dose of guanfacine should be considered.

• haloperidol

  Monitor Closely (1)pentobarbital and haloperidol both increase sedation. Use Caution/Monitor.Minor (1)haloperidol, pentobarbital. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Risk of hyperthermia if haloperidol admin. during barbiturate withdrawal.

• hawthorn

  Monitor Closely (1)hawthorn increases effects of pentobarbital by pharmacodynamic synergism. Use Caution/Monitor. May enhance CNS depression.

• hemin

  Monitor Closely (1)pentobarbital decreases effects of hemin by pharmacodynamic antagonism. Use Caution/Monitor. Drugs that increase delta-aminolevulinic acid synthetase may decrease hemin effect.

• heparin

  Serious - Use Alternative (1)pentobarbital decreases effects of heparin by increasing metabolism. Avoid or Use Alternate Drug.

• hops

  Monitor Closely (1)hops increases effects of pentobarbital by pharmacodynamic synergism. Use Caution/Monitor. May enhance CNS depression.

• hydrocodone

  Monitor Closely (1)pentobarbital will decrease the level or effect of hydrocodone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Caution when discontinuing CYP3A4 inducers that are coadministered with hydrocodone; plasma concentrations of hydrocodone may increase and can result in potentially fatal respiratory depressionSerious - Use Alternative (1)hydrocodone, pentobarbital. Either increases toxicity of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Profound sedation, respiratory depression, coma, and death may result if coadministered. Reserve concomitant prescribing of these drugs in patients for whom other treatment options are inadequate. Limit dosages and durations to the minimum required. Monitor closely for signs of respiratory depression and sedation.

• hydrocortisone

  Monitor Closely (1)pentobarbital will decrease the level or effect of hydrocortisone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• hydromorphone

  Monitor Closely (1)pentobarbital and hydromorphone both increase sedation. Use Caution/Monitor.

• hydroxyprogesterone caproate (DSC)

  Monitor Closely (1)pentobarbital will decrease the level or effect of hydroxyprogesterone caproate (DSC) by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• hydroxyzine

  Monitor Closely (1)hydroxyzine and pentobarbital both increase sedation. Use Caution/Monitor.

• ibrutinib

  Serious - Use Alternative (1)pentobarbital decreases levels of ibrutinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Strong CYP3A inducers decrease ibrutinib plasma concentrations by ~10-fold.

• ibuprofen

  Minor (1)pentobarbital will decrease the level or effect of ibuprofen by affecting hepatic enzyme CYP2C9/10 metabolism. Minor/Significance Unknown.

• ibuprofen IV

  Minor (1)pentobarbital will decrease the level or effect of ibuprofen IV by affecting hepatic enzyme CYP2C9/10 metabolism. Minor/Significance Unknown.

• idelalisib

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of idelalisib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration; strong CYP3A4 inducers significantly decrease idelalisib systemic exposure

• ifosfamide

  Monitor Closely (2)pentobarbital increases effects of ifosfamide by affecting hepatic enzyme CYP2B6 metabolism. Use Caution/Monitor. Coadministration of ifosfamide with CYP2B6 inducers may increase metabolism of ifosfamide to its metabolite. Monitor for increased effects/toxicities if combined with CYP2B6 inducers.
  
  pentobarbital increases toxicity of ifosfamide by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. CYP3A4 inducers may increase the metabolism of ifosfamide to its active alkylating metabolites. CYP3A4 inducers may increase the formation of the neurotoxic/nephrotoxic ifosfamide metabolite, chloroacetaldehyde. Closely monitor patients taking ifosfamide with CYP3A4 inducers for toxicities and consider dose adjustment.

• iloperidone

  Monitor Closely (2)pentobarbital will decrease the level or effect of iloperidone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
  
  pentobarbital and iloperidone both increase sedation. Use Caution/Monitor.

• imatinib

  Minor (1)pentobarbital will decrease the level or effect of imatinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• imipramine

  Monitor Closely (4)pentobarbital will decrease the level or effect of imipramine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.
  
  pentobarbital will decrease the level or effect of imipramine by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.
  
  pentobarbital will decrease the level or effect of imipramine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely.
  
  pentobarbital and imipramine both increase sedation. Use Caution/Monitor.Minor (1)pentobarbital, imipramine. Other (see comment). Minor/Significance Unknown. Comment: Barbiturates may increase adverse effects, including respiratory depression, produced by toxic doses of TCAs. With therapeutic doses of TCAs, barbiturates increase metabolism and decrease blood concentrations of TCAs.

• indinavir

  Monitor Closely (1)pentobarbital will decrease the level or effect of indinavir by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• infigratinib

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of infigratinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• irinotecan

  Monitor Closely (1)pentobarbital will decrease the level or effect of irinotecan by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• irinotecan liposomal

  Monitor Closely (1)pentobarbital will decrease the level or effect of irinotecan liposomal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• isavuconazonium sulfate

  Contraindicated (1)pentobarbital will decrease the level or effect of isavuconazonium sulfate by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated.

• isocarboxazid

  Serious - Use Alternative (1)isocarboxazid, pentobarbital. Other (see comment). Contraindicated. Comment: CNS depressants such as barbiturates should not be used in combination with isocarboxazid.Minor (1)isocarboxazid increases levels of pentobarbital by decreasing metabolism. Minor/Significance Unknown. Theoretical interaction.

• isoproterenol

  Monitor Closely (1)pentobarbital increases and isoproterenol decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• isradipine

  Minor (1)pentobarbital will decrease the level or effect of isradipine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• istradefylline

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of istradefylline by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of istradefylline with strong CYP3A4 inducers.

• itraconazole

  Minor (2)pentobarbital will decrease the level or effect of itraconazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.
  
  pentobarbital decreases levels of itraconazole by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.

• ivabradine

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of ivabradine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of ivabradine with moderate CYP3A4 inducers.

• ivacaftor

  Serious - Use Alternative (1)pentobarbital decreases levels of ivacaftor by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration with strong CYP3A4 inducers; systemic exposure of ivacaftor substantially reduced (ie, ~9-fold).

• ivosidenib

  Serious - Use Alternative (1)pentobarbital will increase the level or effect of ivosidenib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Coadministration of ivosidenib with strong CYP3A4 inducers decreased ivosidenib plasma concentrations.

• ixabepilone

  Monitor Closely (1)pentobarbital will decrease the level or effect of ixabepilone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• ixazomib

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of ixazomib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of ixazomib with strong CYP3A inducers. Strong inducers have been shown to decrease ixazomib Cmax by 54% and AUC by 74%.

• kava

  Monitor Closely (1)kava increases effects of pentobarbital by pharmacodynamic synergism. Use Caution/Monitor. May enhance CNS depression.

• ketamine

  Monitor Closely (1)ketamine and pentobarbital both increase sedation. Use Caution/Monitor.

• ketoconazole

  Minor (2)pentobarbital will decrease the level or effect of ketoconazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.
  
  pentobarbital decreases levels of ketoconazole by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.

• ketotifen, ophthalmic

  Monitor Closely (1)pentobarbital and ketotifen, ophthalmic both increase sedation. Use Caution/Monitor.

• labetalol

  Monitor Closely (1)pentobarbital decreases levels of labetalol by increasing metabolism. Use Caution/Monitor. Consider a higher beta-blocker dose during coadministration of pentobarbital. Atenolol, sotalol, nadolol less likely to be affected than other beta blockers.

• lansoprazole

  Minor (1)pentobarbital will decrease the level or effect of lansoprazole by affecting hepatic enzyme CYP2C19 metabolism. Minor/Significance Unknown.

• lapatinib

  Monitor Closely (1)pentobarbital will decrease the level or effect of lapatinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• larotrectinib

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of larotrectinib with strong CYP3A4 inducers is unavoidable, double larotrectinib dose. Resume prior larotrectinib dose once CYP3A4 inducer discontinued for 3-5 half-lives

• lasmiditan

  Monitor Closely (1)lasmiditan, pentobarbital. Either increases effects of the other by sedation. Use Caution/Monitor. Coadministration of lasmiditan and other CNS depressant drugs, including alcohol have not been evaluated in clinical studies. Lasmiditan may cause sedation, as well as other cognitive and/or neuropsychiatric adverse reactions.

• lefamulin

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of lefamulin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of lefamulin with strong or moderate CYP3A inducers unless the benefit outweighs risks. Monitor for reduced efficacy.

• lemborexant

  Serious - Use Alternative (2)pentobarbital will decrease the level or effect of lemborexant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.
  
  lemborexant, pentobarbital. Either increases effects of the other by sedation. Avoid or Use Alternate Drug. Use of lemborexant with other drugs to treat insomnia is not recommended.

• lenacapavir

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of lenacapavir by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of lenacapavir with moderate CYP3A4 inducers.

• leniolisib

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of leniolisib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• levalbuterol

  Monitor Closely (1)pentobarbital increases and levalbuterol decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• levamlodipine

  Monitor Closely (1)pentobarbital will decrease the level or effect of levamlodipine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. No information is available on the quantitative effects of CYP3A4 inducers on amlodipine. Closely monitor blood pressure when amlodipine is coadministered with CYP3A4 inducers.

• levoketoconazole

  Minor (2)pentobarbital will decrease the level or effect of levoketoconazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.
  
  pentobarbital decreases levels of levoketoconazole by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.

• levonorgestrel intrauterine

  Monitor Closely (1)pentobarbital decreases levels of levonorgestrel intrauterine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• levonorgestrel oral

  Monitor Closely (1)pentobarbital decreases levels of levonorgestrel oral by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• levonorgestrel oral/ethinylestradiol/ferrous bisglycinate

  Monitor Closely (1)pentobarbital will decrease the level or effect of levonorgestrel oral/ethinylestradiol/ferrous bisglycinate by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. The efficacy of hormonal contraceptives may be reduced. Use an alternative method of contraception or a backup method when enzyme inducers are used with combined hormonal contraceptives (CHCs), and continue backup contraception for 28 days after discontinuing enzyme inducer to ensure contraceptive reliability.

• levorphanol

  Monitor Closely (1)pentobarbital and levorphanol both increase sedation. Use Caution/Monitor.

• levothyroxine

  Minor (1)pentobarbital decreases levels of levothyroxine by increasing metabolism. Minor/Significance Unknown.

• lidocaine

  Monitor Closely (1)pentobarbital will decrease the level or effect of lidocaine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.

• linagliptin

  Monitor Closely (1)pentobarbital will decrease the level or effect of linagliptin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Use of alternative treatments is strongly recommended when linagliptin is to be administered with a CYP3A4 inducer

• linezolid

  Minor (1)linezolid increases levels of pentobarbital by decreasing metabolism. Minor/Significance Unknown. Theoretical interaction.

• liothyronine

  Minor (1)pentobarbital decreases levels of liothyronine by increasing metabolism. Minor/Significance Unknown.

• lisdexamfetamine

  Monitor Closely (1)pentobarbital increases and lisdexamfetamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• lofepramine

  Monitor Closely (1)pentobarbital and lofepramine both increase sedation. Use Caution/Monitor.Minor (1)pentobarbital, lofepramine. Other (see comment). Minor/Significance Unknown. Comment: Barbiturates may increase adverse effects, including respiratory depression, produced by toxic doses of TCAs. With therapeutic doses of TCAs, barbiturates increase metabolism and decrease blood concentrations of TCAs.

• lofexidine

  Monitor Closely (1)pentobarbital and lofexidine both increase sedation. Use Caution/Monitor.

• lonafarnib

  Contraindicated (1)pentobarbital will decrease the level or effect of lonafarnib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated. Lonafarnib is a sensitive CYP3A4 substrate. Coadministration with strong or moderate CYP3A4 inducers is contraindicated.

• lopinavir

  Monitor Closely (1)pentobarbital will decrease the level or effect of lopinavir by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• loprazolam

  Monitor Closely (1)pentobarbital and loprazolam both increase sedation. Use Caution/Monitor.

• loratadine

  Monitor Closely (1)pentobarbital will decrease the level or effect of loratadine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• lorazepam

  Monitor Closely (1)pentobarbital and lorazepam both increase sedation. Use Caution/Monitor.

• lorlatinib

  Contraindicated (1)pentobarbital will decrease the level or effect of lorlatinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated. Coadministration of lorlatinib with strong CYP3A inducers is contraindicated. Discontinue the strong CYP3A inducer for 3 plasma half-lives before initiating lorlatinib.

• lormetazepam

  Monitor Closely (1)pentobarbital and lormetazepam both increase sedation. Use Caution/Monitor.

• losartan

  Minor (1)pentobarbital will decrease the level or effect of losartan by affecting hepatic enzyme CYP2C9/10 metabolism. Minor/Significance Unknown.

• lovastatin

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of lovastatin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• loxapine

  Monitor Closely (1)pentobarbital and loxapine both increase sedation. Use Caution/Monitor.

• loxapine inhaled

  Monitor Closely (1)pentobarbital and loxapine inhaled both increase sedation. Use Caution/Monitor.

• lumacaftor/ivacaftor

  Contraindicated (1)pentobarbital will decrease the level or effect of lumacaftor/ivacaftor by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated. Strong CYP3A inducers have minimal effect on lumacaftor exposure, but decreased ivacaftor exposure (AUC) by 57%. This may reduce the effectiveness of lumacaftor/ivacaftor. Therefore, coadministration is not recommended.

• lumateperone

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of lumateperone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• lumefantrine

  Contraindicated (1)pentobarbital will decrease the level or effect of lumefantrine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated. Coadministration with strong CYP3A4 inducers can result in decreased serum concentrations and loss of antimalarial efficacy

• lurasidone

  Contraindicated (1)pentobarbital decreases levels of lurasidone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated. Contraindicated.Monitor Closely (1)lurasidone, pentobarbital. Either increases toxicity of the other by Other (see comment). Use Caution/Monitor. Comment: Potential for increased CNS depressant effects when used concurrently; monitor for increased adverse effects and toxicity.

• lurbinectedin

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of lurbinectedin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• macimorelin

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of macimorelin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Potential for false positive test results if macimorelin and strong CYP3A4 inducers are coadministered. Discontinue strong CYP3A4 inducer, allowing for sufficient washout time, before testing.

• macitentan

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of macitentan by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministering macitentan with strong CYP3A4 inducers

• maprotiline

  Monitor Closely (1)pentobarbital and maprotiline both increase sedation. Use Caution/Monitor.Minor (1)pentobarbital, maprotiline. Other (see comment). Minor/Significance Unknown. Comment: Barbiturates may increase adverse effects, including respiratory depression, produced by toxic doses of TCAs. With therapeutic doses of TCAs, barbiturates increase metabolism and decrease blood concentrations of TCAs.

• maraviroc

  Monitor Closely (1)pentobarbital will decrease the level or effect of maraviroc by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• marijuana

  Monitor Closely (1)pentobarbital and marijuana both increase sedation. Use Caution/Monitor.

• mavacamten

  Contraindicated (1)pentobarbital will decrease the level or effect of mavacamten by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated.

• medroxyprogesterone

  Monitor Closely (1)pentobarbital will decrease the level or effect of medroxyprogesterone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Contraceptirve failure possible. Use alternative if available.

• melatonin

  Monitor Closely (1)pentobarbital and melatonin both increase sedation. Use Caution/Monitor.

• meloxicam

  Minor (1)pentobarbital will decrease the level or effect of meloxicam by affecting hepatic enzyme CYP2C9/10 metabolism. Minor/Significance Unknown.

• meperidine

  Monitor Closely (1)pentobarbital and meperidine both increase sedation. Use Caution/Monitor.

• meprobamate

  Monitor Closely (1)pentobarbital and meprobamate both increase sedation. Use Caution/Monitor.

• mestranol

  Monitor Closely (1)pentobarbital will decrease the level or effect of mestranol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.Serious - Use Alternative (1)pentobarbital decreases levels of mestranol by increasing metabolism. Avoid or Use Alternate Drug. May result in contraceptive failure.

• metaproterenol

  Monitor Closely (1)pentobarbital increases and metaproterenol decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• metaxalone

  Monitor Closely (1)pentobarbital and metaxalone both increase sedation. Use Caution/Monitor.

• methadone

  Monitor Closely (2)pentobarbital will decrease the level or effect of methadone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
  
  pentobarbital and methadone both increase sedation. Use Caution/Monitor.

• methamphetamine

  Monitor Closely (1)pentobarbital increases and methamphetamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• methazolamide

  Minor (1)methazolamide, pentobarbital. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Increased risk of anticonvulsant induced osteomalacia.

• methocarbamol

  Monitor Closely (1)pentobarbital and methocarbamol both increase sedation. Use Caution/Monitor.

• methoxyflurane

  Serious - Use Alternative (1)pentobarbital increases toxicity of methoxyflurane by increasing metabolism. Contraindicated. Increased metabolism of methoxyflurane to nephrotoxic compounds.

• methsuximide

  Minor (1)methsuximide decreases effects of pentobarbital by pharmacodynamic antagonism. Minor/Significance Unknown.

• methylenedioxymethamphetamine

  Monitor Closely (1)pentobarbital increases and methylenedioxymethamphetamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• methylprednisolone

  Monitor Closely (1)pentobarbital will decrease the level or effect of methylprednisolone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• metoclopramide intranasal

  Serious - Use Alternative (1)pentobarbital, metoclopramide intranasal. Either increases effects of the other by Other (see comment). Avoid or Use Alternate Drug. Comment: Avoid use of metoclopramide intranasal or interacting drug, depending on importance of drug to patient.

• metoprolol

  Monitor Closely (1)pentobarbital decreases levels of metoprolol by increasing metabolism. Use Caution/Monitor. Consider a higher beta-blocker dose during coadministration of pentobarbital. Atenolol, sotalol, nadolol less likely to be affected than other beta blockers.

• mexiletine

  Monitor Closely (1)pentobarbital will decrease the level or effect of mexiletine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.

• miconazole vaginal

  Minor (1)pentobarbital decreases levels of miconazole vaginal by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.

• midazolam

  Monitor Closely (2)pentobarbital will decrease the level or effect of midazolam by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
  
  pentobarbital and midazolam both increase sedation. Use Caution/Monitor.

• midazolam intranasal

  Monitor Closely (1)midazolam intranasal, pentobarbital. Either increases toxicity of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Concomitant use of barbiturates, alcohol, or other CNS depressants may increase the risk of hypoventilation, airway obstruction, desaturation, or apnea and may contribute to profound and/or prolonged drug effect.

• midodrine

  Monitor Closely (1)pentobarbital increases and midodrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• midostaurin

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of midostaurin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Strong CYP3A4 inducers may decrease midostaurin concentrations resulting in reduced efficacy.

• mifepristone

  Monitor Closely (1)pentobarbital will decrease the level or effect of mifepristone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. CYP3A4 inducers have not been studied, coadministration not recommended by manufacturer

• mirtazapine

  Monitor Closely (1)pentobarbital and mirtazapine both increase sedation. Use Caution/Monitor.

• mobocertinib

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of mobocertinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• modafinil

  Monitor Closely (1)pentobarbital increases and modafinil decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• montelukast

  Minor (1)pentobarbital will decrease the level or effect of montelukast by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• morphine

  Monitor Closely (1)pentobarbital and morphine both increase sedation. Use Caution/Monitor.

• motherwort

  Monitor Closely (1)pentobarbital and motherwort both increase sedation. Use Caution/Monitor.

• moxonidine

  Monitor Closely (1)pentobarbital and moxonidine both increase sedation. Use Caution/Monitor.

• nabilone

  Monitor Closely (1)pentobarbital and nabilone both increase sedation. Use Caution/Monitor.

• nadolol

  Monitor Closely (1)pentobarbital decreases levels of nadolol by increasing metabolism. Use Caution/Monitor. Atenolol, sotalol, nadolol less likely to be affected than other beta blockers.

• nalbuphine

  Monitor Closely (1)pentobarbital and nalbuphine both increase sedation. Use Caution/Monitor.

• naldemedine

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of naldemedine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration with strong CYP3A4 inducers.

• naloxegol

  Contraindicated (1)pentobarbital will decrease the level or effect of naloxegol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated. Use of naloxegol with strong CYP3A4 inducers is not recommended

• nateglinide

  Monitor Closely (1)pentobarbital will decrease the level or effect of nateglinide by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.

• nebivolol

  Monitor Closely (1)pentobarbital decreases levels of nebivolol by increasing metabolism. Use Caution/Monitor. Consider a higher beta-blocker dose during coadministration of pentobarbital. Atenolol, sotalol, nadolol less likely to be affected than other beta blockers.

• nelfinavir

  Monitor Closely (1)pentobarbital will decrease the level or effect of nelfinavir by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• neratinib

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of neratinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of neratinib with strong/moderate CYP3A4 inducers.

• nettle

  Minor (1)nettle increases effects of pentobarbital by pharmacodynamic synergism. Minor/Significance Unknown. (High dose nettle; theoretical interaction) May enhance CNS depression.

• netupitant/palonosetron

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of netupitant/palonosetron by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Netupitant is mainly metabolized by CYP3A4; avoid use in patients who are chronically using a strong CYP3A4 inducer

• nicardipine

  Monitor Closely (1)pentobarbital will decrease the level or effect of nicardipine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• nifedipine

  Monitor Closely (1)pentobarbital will decrease the level or effect of nifedipine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely.

• nilotinib

  Monitor Closely (1)pentobarbital will decrease the level or effect of nilotinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• nimodipine

  Minor (1)pentobarbital will decrease the level or effect of nimodipine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• nisoldipine

  Monitor Closely (1)pentobarbital will decrease the level or effect of nisoldipine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• nitrendipine

  Minor (1)pentobarbital will decrease the level or effect of nitrendipine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• norepinephrine

  Monitor Closely (1)pentobarbital increases and norepinephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• nortriptyline

  Monitor Closely (1)pentobarbital and nortriptyline both increase sedation. Use Caution/Monitor.Minor (1)pentobarbital, nortriptyline. Other (see comment). Minor/Significance Unknown. Comment: Barbiturates may increase adverse effects, including respiratory depression, produced by toxic doses of TCAs. With therapeutic doses of TCAs, barbiturates increase metabolism and decrease blood concentrations of TCAs.

• olanzapine

  Monitor Closely (2)pentobarbital will decrease the level or effect of olanzapine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.
  
  pentobarbital and olanzapine both increase sedation. Use Caution/Monitor.

• olaparib

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of olaparib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of olaparib with strong CYP3A4 inducers.

• oliceridine

  Monitor Closely (2)pentobarbital will decrease the level or effect of oliceridine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. If coadministration with a CYP3A4 inducer is necessary, consider increasing oliceridine dose until stable drug effects are achieved; monitor for signs of opioid withdrawal. If inducer is discontinued, consider oliceridine dosage reduction and monitor for signs of respiratory depression.
  
  oliceridine, pentobarbital. Either increases toxicity of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Profound sedation, respiratory depression, coma, and death may result if coadministered. Reserve concomitant prescribing of these drugs in patients for whom other treatment options are inadequate. Limit dosages and durations to the minimum required. Monitor closely for signs of respiratory depression and sedation.

• olopatadine intranasal

  Serious - Use Alternative (1)pentobarbital and olopatadine intranasal both increase sedation. Avoid or Use Alternate Drug. Coadministration increases risk of CNS depression, which can lead to additive impairment of psychomotor performance and cause daytime impairment.

• olutasidenib

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of olutasidenib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Strong or moderate CYP3A inducers decrease olutasidenib (a CYP3A4 substrate) plasma concentrations and efficacy.

• omaveloxolone

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of omaveloxolone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• ombitasvir/paritaprevir/ritonavir & dasabuvir (DSC)

  Contraindicated (1)pentobarbital will decrease the level or effect of ombitasvir/paritaprevir/ritonavir & dasabuvir (DSC) by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated. Strong CYP3A4 inducers may reduce partiaprevir and ritonavir levels, and therefore decreased efficacy of Viekira Pak

• omeprazole

  Monitor Closely (1)pentobarbital will decrease the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.

• ondansetron

  Monitor Closely (1)pentobarbital will decrease the level or effect of ondansetron by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. No dosage adjustment for ondansetron is recommended for patients on these drugs.Minor (1)pentobarbital will decrease the level or effect of ondansetron by affecting hepatic enzyme CYP1A2 metabolism. Minor/Significance Unknown.

• opium tincture

  Monitor Closely (1)pentobarbital and opium tincture both increase sedation. Use Caution/Monitor.

• orphenadrine

  Monitor Closely (1)pentobarbital and orphenadrine both increase sedation. Use Caution/Monitor.

• osilodrostat

  Monitor Closely (1)pentobarbital will decrease the level or effect of osilodrostat by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Monitor cortisol concentration and patient?s signs and symptoms during coadministration or discontinuation with strong CYP3A4 inducers. Adjust dose of osilodrostat if necessary.

• osimertinib

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of osimertinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid concomitant use of osimertinib with strong CYP3A inducers.

• ospemifene

  Monitor Closely (1)pentobarbital decreases levels of ospemifene by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• oxazepam

  Monitor Closely (1)pentobarbital and oxazepam both increase sedation. Use Caution/Monitor.

• oxybutynin

  Minor (1)pentobarbital will decrease the level or effect of oxybutynin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• oxycodone

  Monitor Closely (2)pentobarbital decreases levels of oxycodone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
  
  pentobarbital and oxycodone both increase sedation. Use Caution/Monitor.

• oxymorphone

  Monitor Closely (1)pentobarbital and oxymorphone both increase sedation. Use Caution/Monitor.

• paclitaxel

  Minor (1)pentobarbital will decrease the level or effect of paclitaxel by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• paclitaxel protein bound

  Minor (1)pentobarbital will decrease the level or effect of paclitaxel protein bound by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• pacritinib

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of pacritinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• palbociclib

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of palbociclib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Strong CYP3A inducers decrease palbociclib plasma exposure by ~85%.

• paliperidone

  Monitor Closely (1)pentobarbital and paliperidone both increase sedation. Use Caution/Monitor.

• panobinostat

  Contraindicated (1)pentobarbital decreases levels of panobinostat by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated. Strong CYP3A4 inducers can reduce panobinostat levels by ~70% and lead to treatment failure.

• pantoprazole

  Minor (1)pentobarbital will decrease the level or effect of pantoprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• papaveretum

  Monitor Closely (1)pentobarbital and papaveretum both increase sedation. Use Caution/Monitor.

• papaverine

  Monitor Closely (1)pentobarbital and papaverine both increase sedation. Use Caution/Monitor.

• parecoxib

  Monitor Closely (1)pentobarbital will decrease the level or effect of parecoxib by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.Minor (1)pentobarbital will decrease the level or effect of parecoxib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• passion flower

  Monitor Closely (1)passion flower increases effects of pentobarbital by pharmacodynamic synergism. Use Caution/Monitor. May enhance CNS depression.

• pazopanib

  Monitor Closely (1)pentobarbital will decrease the level or effect of pazopanib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• pemigatinib

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of pemigatinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• penbutolol

  Monitor Closely (1)pentobarbital decreases levels of penbutolol by increasing metabolism. Use Caution/Monitor. Consider a higher beta-blocker dose during coadministration of pentobarbital. Atenolol, sotalol, nadolol less likely to be affected than other beta blockers.

• pentazocine

  Monitor Closely (1)pentobarbital and pentazocine both increase sedation. Use Caution/Monitor.

• perphenazine

  Monitor Closely (1)pentobarbital and perphenazine both increase sedation. Use Caution/Monitor.

• pexidartinib

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of pexidartinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• phendimetrazine

  Monitor Closely (1)pentobarbital increases and phendimetrazine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• phenelzine

  Minor (1)phenelzine increases levels of pentobarbital by decreasing metabolism. Minor/Significance Unknown. Theoretical interaction.

• phenindione

  Serious - Use Alternative (1)pentobarbital decreases effects of phenindione by increasing metabolism. Avoid or Use Alternate Drug.

• phenobarbital

  Monitor Closely (1)pentobarbital and phenobarbital both increase sedation. Use Caution/Monitor.

• phentermine

  Monitor Closely (1)pentobarbital increases and phentermine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• phenylephrine

  Monitor Closely (1)pentobarbital increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• phenylephrine PO

  Monitor Closely (1)pentobarbital increases and phenylephrine PO decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. .

• phenytoin

  Monitor Closely (1)pentobarbital will decrease the level or effect of phenytoin by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.

• pholcodine

  Monitor Closely (1)pentobarbital and pholcodine both increase sedation. Use Caution/Monitor.

• pimavanserin

  Monitor Closely (1)pentobarbital will decrease the level or effect of pimavanserin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Avoid coadministration if possible. Monitor for reduced pimavanserin efficacy. An increase in pimavanserin dosage may be needed.

• pimozide

  Monitor Closely (1)pentobarbital and pimozide both increase sedation. Use Caution/Monitor.Minor (1)pentobarbital will decrease the level or effect of pimozide by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• pindolol

  Monitor Closely (1)pentobarbital decreases levels of pindolol by increasing metabolism. Use Caution/Monitor. Consider a higher beta-blocker dose during coadministration of pentobarbital. Atenolol, sotalol, nadolol less likely to be affected than other beta blockers.

• pioglitazone

  Minor (1)pentobarbital will decrease the level or effect of pioglitazone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• pirbuterol

  Monitor Closely (1)pentobarbital increases and pirbuterol decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• piroxicam

  Minor (1)pentobarbital will decrease the level or effect of piroxicam by affecting hepatic enzyme CYP2C9/10 metabolism. Minor/Significance Unknown.

• pitolisant

  Monitor Closely (1)pentobarbital will decrease the level or effect of pitolisant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Pitolisant exposure is decreased by 50% if coadministered with strong CYP3A4 inducers. For patients stable on pitolisant 8.9 mg/day or 17.8 mg/day, double the pitolisant dose (ie, 17.8 mg or 35.6 mg, respectively) over 7 days. If the strong CYP3A4 inducer is discontinued, reduce pitolisant dosage by half.

• polatuzumab vedotin

  Monitor Closely (1)pentobarbital will decrease the level or effect of polatuzumab vedotin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Polatuzumab undergoes catabolism to small peptides, amino acids, monomethyl auristatin E (MMAE), and unconjugated MMAE-related catabolites. MMAE is a CYP3A4 substrate. Coadministration of polatuzumab vedotin with a strong CYP3A4 inducer may decrease unconjugated MMAE AUC.

• pomalidomide

  Serious - Use Alternative (1)pentobarbital decreases levels of pomalidomide by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• ponatinib

  Serious - Use Alternative (1)pentobarbital decreases levels of ponatinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid unless the coadministration outweighs the possible risk of ponatinib underexposure; monitor for signs of reduced efficacy.

• posaconazole

  Minor (1)pentobarbital decreases levels of posaconazole by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.

• pralsetinib

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of pralsetinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If unable to avoid, double current pralsetinib dose starting on Day 7 of coadministration with strong CYP3A inducer. After inducer has been discontinued for at least 14 days, resume previous pralsetinib dose.

• praziquantel

  Contraindicated (1)pentobarbital decreases levels of praziquantel by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated. Strong CYP450 inducers significantly decrease praziquantel blood levels.

• prednisone

  Monitor Closely (1)pentobarbital will decrease the level or effect of prednisone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• pregabalin

  Monitor Closely (1)pregabalin, pentobarbital. Either increases effects of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of CNS depressants can result in serious, life-threatening, and fatal respiratory depression. Use lowest dose possible and monitor for respiratory depression and sedation.

• pretomanid

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of pretomanid by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Pretomanid is a CYP3A4 substrate. Avoid coadministration of strong or moderate CYP3A4. inducers

• primidone

  Monitor Closely (1)pentobarbital and primidone both increase sedation. Use Caution/Monitor.

• prochlorperazine

  Monitor Closely (1)pentobarbital and prochlorperazine both increase sedation. Use Caution/Monitor.

• promethazine

  Monitor Closely (1)promethazine and pentobarbital both increase sedation. Use Caution/Monitor.

• propafenone

  Monitor Closely (1)pentobarbital decreases levels of propafenone by increasing metabolism. Use Caution/Monitor.Minor (1)pentobarbital will decrease the level or effect of propafenone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• propofol

  Monitor Closely (1)propofol and pentobarbital both increase sedation. Use Caution/Monitor.

• propranolol

  Monitor Closely (1)pentobarbital decreases levels of propranolol by increasing metabolism. Use Caution/Monitor. Consider a higher beta-blocker dose during coadministration of pentobarbital. Atenolol, sotalol, nadolol less likely to be affected than other beta blockers.

• propylhexedrine

  Monitor Closely (1)pentobarbital increases and propylhexedrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• protamine

  Serious - Use Alternative (1)pentobarbital decreases effects of protamine by increasing metabolism. Avoid or Use Alternate Drug.

• protriptyline

  Monitor Closely (1)pentobarbital and protriptyline both increase sedation. Use Caution/Monitor.Minor (1)pentobarbital, protriptyline. Other (see comment). Minor/Significance Unknown. Comment: Barbiturates may increase adverse effects, including respiratory depression, produced by toxic doses of TCAs. With therapeutic doses of TCAs, barbiturates increase metabolism and decrease blood concentrations of TCAs.

• quazepam

  Monitor Closely (1)pentobarbital and quazepam both increase sedation. Use Caution/Monitor.

• quetiapine

  Monitor Closely (2)pentobarbital will decrease the level or effect of quetiapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
  
  pentobarbital and quetiapine both increase sedation. Use Caution/Monitor.

• quinidine

  Monitor Closely (1)pentobarbital will decrease the level or effect of quinidine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• quinine

  Minor (1)pentobarbital will decrease the level or effect of quinine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• rabeprazole

  Minor (1)pentobarbital will decrease the level or effect of rabeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• ramelteon

  Monitor Closely (2)pentobarbital will decrease the level or effect of ramelteon by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.
  
  pentobarbital and ramelteon both increase sedation. Use Caution/Monitor.Minor (2)pentobarbital will decrease the level or effect of ramelteon by affecting hepatic enzyme CYP2C9/10 metabolism. Minor/Significance Unknown.
  
  pentobarbital will decrease the level or effect of ramelteon by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• ranolazine

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of ranolazine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• regorafenib

  Contraindicated (1)pentobarbital, regorafenib. affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated. Strong CYP3A4 inducers decrease regorafenib levels and increase exposure of the active metabolite M-5.

• remimazolam

  Monitor Closely (1)remimazolam, pentobarbital. Either increases toxicity of the other by sedation. Modify Therapy/Monitor Closely. Coadministration may result in profound sedation, respiratory depression, coma, and/or death. Continuously monitor vital signs during sedation and recovery period if coadministered. Carefully titrate remimazolam dose if administered with opioid analgesics and/or sedative/hypnotics.

• repaglinide

  Monitor Closely (1)pentobarbital will decrease the level or effect of repaglinide by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• rifampin

  Monitor Closely (1)rifampin decreases levels of pentobarbital by increasing metabolism. Use Caution/Monitor.

• riluzole

  Minor (1)pentobarbital will decrease the level or effect of riluzole by affecting hepatic enzyme CYP1A2 metabolism. Minor/Significance Unknown.

• rimegepant

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of rimegepant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• riociguat

  Monitor Closely (1)pentobarbital will decrease the level or effect of riociguat by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Data not available for dose adjustment

• ripretinib

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of ripretinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Coadministration with a strong CYP3A inhibitor will decrease systemic exposure to ripretinib and its active metabolite (DP-5439), which may decrease risk of adverse reactions.

• risperidone

  Monitor Closely (1)pentobarbital and risperidone both increase sedation. Use Caution/Monitor.

• ritonavir

  Monitor Closely (1)pentobarbital will decrease the level or effect of ritonavir by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• roflumilast

  Contraindicated (1)pentobarbital will decrease the level or effect of roflumilast by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated. Coadministration not recommended; strong cytochrome P450 enzyme inducers decrease systemic exposure to roflumilast and may reduce the therapeutic effectiveness

• rolapitant

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of rolapitant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Long-term coadministration of strong CYP3A4 inducers with rolapitant may significantly decrease rolapitant efficacy.

• romidepsin

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of romidepsin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• rose hips

  Minor (1)pentobarbital decreases levels of rose hips by increasing elimination. Minor/Significance Unknown.

• sage

  Minor (1)pentobarbital and sage both increase sedation. Minor/Significance Unknown.

• salmeterol

  Monitor Closely (1)pentobarbital increases and salmeterol decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• saquinavir

  Monitor Closely (1)pentobarbital will decrease the level or effect of saquinavir by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• saxagliptin

  Minor (1)pentobarbital will decrease the level or effect of saxagliptin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• scullcap

  Monitor Closely (1)pentobarbital and scullcap both increase sedation. Use Caution/Monitor.

• secobarbital

  Monitor Closely (1)pentobarbital and secobarbital both increase sedation. Use Caution/Monitor.

• selegiline transdermal

  Minor (1)selegiline transdermal increases levels of pentobarbital by decreasing metabolism. Minor/Significance Unknown. Theoretical interaction.

• selinexor

  Serious - Use Alternative (1)selinexor, pentobarbital. unspecified interaction mechanism. Avoid or Use Alternate Drug. Patients treated with selinexor may experience neurological toxicities. Avoid taking selinexor with other medications that may cause dizziness or confusion.

• selumetinib

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of selumetinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• sevoflurane

  Monitor Closely (1)sevoflurane and pentobarbital both increase sedation. Use Caution/Monitor.

• shepherd's purse

  Monitor Closely (1)pentobarbital and shepherd's purse both increase sedation. Use Caution/Monitor.

• Siberian ginseng

  Minor (1)Siberian ginseng increases effects of pentobarbital by pharmacodynamic synergism. Minor/Significance Unknown. May enhance CNS depression.

• sildenafil

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Potent CYP3A4 inducers are expected to cause substantial decreases in sildenafil plasma levels

• silodosin

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of silodosin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• simvastatin

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of simvastatin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• siponimod

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of siponimod by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Coadministration of siponimod with a drug that causes moderate CYP2C9 plus a moderate or strong CYP3A4 inducer is not recommended. Coadministration with moderate or strong CYP3A4 inducers alone is not recommended for patients with CYP2C9*1/*3 and*2/*3 genotype.

• sirolimus

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of sirolimus by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• sodium oxybate

  Serious - Use Alternative (1)pentobarbital, sodium oxybate. Either increases effects of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Profound sedation, respiratory depression, coma, and death may result if coadministered. Reserve concomitant prescribing of these drugs in patients for whom other treatment options are inadequate. Limit dosages and durations to the minimum required. Monitor closely for signs of respiratory depression and sedation.

• sofosbuvir/velpatasvir

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of sofosbuvir/velpatasvir by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Velpatasvir is a substrate of CYP2B6, CYP2C8, and CYP3A4. Drugs that are moderate-to-potent inducers of CYP2B6, CYP2C8, or CYP3A4 may significantly decrease velpatasvir plasma concentrations, leading to potentially reduced therapeutic effect.

• solifenacin

  Monitor Closely (1)pentobarbital will decrease the level or effect of solifenacin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• sonidegib

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of sonidegib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of sonidegib with strong or moderate CYP3A4 inducers.

• sorafenib

  Monitor Closely (1)pentobarbital decreases levels of sorafenib by increasing metabolism. Use Caution/Monitor.

• sotalol

  Monitor Closely (1)pentobarbital decreases levels of sotalol by increasing metabolism. Use Caution/Monitor. Consider a higher beta-blocker dose during coadministration of pentobarbital. Atenolol, sotalol, nadolol less likely to be affected than other beta blockers.

• sotorasib

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of sotorasib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• stiripentol

  Monitor Closely (1)stiripentol, pentobarbital. Either increases effects of the other by sedation. Use Caution/Monitor. Concomitant use stiripentol with other CNS depressants, including alcohol, may increase the risk of sedation and somnolence.Serious - Use Alternative (1)pentobarbital will decrease the level or effect of stiripentol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If unable to avoid coadministration of stiripentol with strong CYP3A4 inducers, increase stiripentol dose.

• sufentanil

  Monitor Closely (1)pentobarbital and sufentanil both increase sedation. Use Caution/Monitor.Minor (1)pentobarbital will decrease the level or effect of sufentanil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• sufentanil SL

  Monitor Closely (1)pentobarbital decreases effects of sufentanil SL by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Coadministration of CYP3A4 inducers may decrease sufentanil levels and efficacy, possibly precipitating withdrawal syndrome in patients who have developed physical dependence to sufentanil. Discontinuation of concomitantly used CYP3A4 inducers may increase sufentanil plasma concentration.Serious - Use Alternative (1)sufentanil SL, pentobarbital. Either increases toxicity of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Coadministration may result in hypotension, profound sedation, respiratory depression, coma, and death. Reserve concomitant prescribing of these drugs in patients for whom other treatment options are inadequate. Limit dosages and durations to the minimum required. Monitor closely for signs of respiratory depression and sedation.

• sulfamethoxazole

  Minor (1)pentobarbital will decrease the level or effect of sulfamethoxazole by affecting hepatic enzyme CYP2C9/10 metabolism. Minor/Significance Unknown.

• sunitinib

  Monitor Closely (1)pentobarbital will decrease the level or effect of sunitinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• suvorexant

  Monitor Closely (2)pentobarbital will decrease the level or effect of suvorexant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Strong CYP3A4 inducers may decrease suvorexant efficacy; if increased suvorexant dose required, do not exceed 20 mg/day
  
  suvorexant and pentobarbital both increase sedation. Modify Therapy/Monitor Closely. Dosage adjustments of suvorexant and concomitant CNS depressants may be necessary

• tacrolimus

  Monitor Closely (1)pentobarbital will decrease the level or effect of tacrolimus by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• tadalafil

  Monitor Closely (1)pentobarbital will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Avoid combination in pulmonary HTN patients. For patients with ED, monitor response to tadalafil carefully because of potential for decreased effectiveness.

• tamoxifen

  Monitor Closely (2)pentobarbital will decrease the level or effect of tamoxifen by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.
  
  pentobarbital will decrease the level or effect of tamoxifen by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• tapentadol

  Monitor Closely (1)pentobarbital and tapentadol both increase sedation. Use Caution/Monitor.

• tasimelteon

  Monitor Closely (1)pentobarbital will decrease the level or effect of tasimelteon by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Avoid coadministration of tasimelteon with strong CYP3A4 inducers

• tazemetostat

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of tazemetostat by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• temazepam

  Monitor Closely (1)pentobarbital and temazepam both increase sedation. Use Caution/Monitor.

• temsirolimus

  Monitor Closely (1)pentobarbital will decrease the level or effect of temsirolimus by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• terbinafine

  Monitor Closely (1)pentobarbital will decrease the level or effect of terbinafine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• terbutaline

  Monitor Closely (1)pentobarbital increases and terbutaline decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• tezacaftor

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of tezacaftor by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• thalidomide

  Monitor Closely (1)thalidomide increases effects of pentobarbital by unspecified interaction mechanism. Use Caution/Monitor. Increased sedative effects.

• theophylline

  Monitor Closely (2)pentobarbital will decrease the level or effect of theophylline by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.
  
  pentobarbital will decrease the level or effect of theophylline by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• thioridazine

  Monitor Closely (1)pentobarbital and thioridazine both increase sedation. Use Caution/Monitor.Minor (1)thioridazine decreases levels of pentobarbital by unspecified interaction mechanism. Minor/Significance Unknown.

• thiothixene

  Monitor Closely (1)pentobarbital and thiothixene both increase sedation. Use Caution/Monitor.

• thyroid desiccated

  Minor (1)pentobarbital decreases levels of thyroid desiccated by increasing metabolism. Minor/Significance Unknown.

• tibolone

  Minor (1)pentobarbital decreases levels of tibolone by increasing metabolism. Minor/Significance Unknown. Theoretical interaction.

• timolol

  Monitor Closely (1)pentobarbital decreases levels of timolol by increasing metabolism. Use Caution/Monitor. Consider a higher beta-blocker dose during coadministration of pentobarbital. Atenolol, sotalol, nadolol less likely to be affected than other beta blockers.

• tinidazole

  Monitor Closely (1)pentobarbital will decrease the level or effect of tinidazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• tipranavir

  Monitor Closely (1)pentobarbital will decrease the level or effect of tipranavir by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• tivozanib

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of tivozanib by affecting hepatic enzyme CYP2E1 metabolism. Avoid or Use Alternate Drug.

• tizanidine

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of tizanidine by affecting hepatic enzyme CYP1A2 metabolism. Avoid or Use Alternate Drug.

• tofacitinib

  Monitor Closely (1)pentobarbital will decrease the level or effect of tofacitinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Loss of, or decreased response to tofacitinib may occur when coadministered with potent CYP3A4 inducers

• tolbutamide

  Minor (1)pentobarbital will decrease the level or effect of tolbutamide by affecting hepatic enzyme CYP2C9/10 metabolism. Minor/Significance Unknown.

• tolterodine

  Monitor Closely (1)pentobarbital will decrease the level or effect of tolterodine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• tolvaptan

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of tolvaptan by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• topiramate

  Monitor Closely (1)pentobarbital and topiramate both increase sedation. Modify Therapy/Monitor Closely.Minor (1)pentobarbital decreases levels of topiramate by increasing metabolism. Minor/Significance Unknown.

• toremifene

  Monitor Closely (1)pentobarbital decreases levels of toremifene by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. CYP3A4 inducers increase rate of toremifene metabolism, lowering the steady-state concentration in serum.

• trabectedin

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of trabectedin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• tramadol

  Monitor Closely (2)pentobarbital will decrease the level or effect of tramadol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Decreased AUC of tramadol and the active metabolite (O-desmethyltramadol) when coadministered with strong CYP3A4 and CYP2B6 inducers
  
  pentobarbital and tramadol both increase sedation. Use Caution/Monitor.

• tranylcypromine

  Minor (1)tranylcypromine increases levels of pentobarbital by decreasing metabolism. Minor/Significance Unknown. Theoretical interaction.

• trazodone

  Monitor Closely (2)pentobarbital will decrease the level or effect of trazodone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
  
  pentobarbital and trazodone both increase sedation. Use Caution/Monitor.Minor (1)pentobarbital, trazodone. Other (see comment). Minor/Significance Unknown. Comment: Barbiturates may increase adverse effects, including respiratory depression, produced by toxic doses of TCAs. With therapeutic doses of TCAs, barbiturates increase metabolism and decrease blood concentrations of TCAs.

• triamcinolone acetonide injectable suspension

  Monitor Closely (1)pentobarbital will decrease the level or effect of triamcinolone acetonide injectable suspension by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• triazolam

  Monitor Closely (2)pentobarbital will decrease the level or effect of triazolam by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
  
  pentobarbital and triazolam both increase sedation. Use Caution/Monitor.

• triclofos

  Monitor Closely (1)pentobarbital and triclofos both increase sedation. Use Caution/Monitor.

• trifluoperazine

  Monitor Closely (1)pentobarbital and trifluoperazine both increase sedation. Use Caution/Monitor.

• trimipramine

  Monitor Closely (1)pentobarbital and trimipramine both increase sedation. Use Caution/Monitor.Minor (1)pentobarbital, trimipramine. Other (see comment). Minor/Significance Unknown. Comment: Barbiturates may increase adverse effects, including respiratory depression, produced by toxic doses of TCAs. With therapeutic doses of TCAs, barbiturates increase metabolism and decrease blood concentrations of TCAs.

• triprolidine

  Monitor Closely (1)triprolidine and pentobarbital both increase sedation. Use Caution/Monitor.

• tucatinib

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of tucatinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• ubrogepant

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of ubrogepant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• upadacitinib

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of upadacitinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid upadacitinib coadministration with strong CYP3A4 inducers.

• valbenazine

  Serious - Use Alternative (1)pentobarbital will increase the level or effect of valbenazine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Concomitant use not recommended.

• valerian

  Serious - Use Alternative (2)valerian increases effects of pentobarbital by pharmacodynamic synergism. Avoid or Use Alternate Drug. May enhance CNS depression.
  
  valerian and pentobarbital both increase sedation. Avoid or Use Alternate Drug.

• vandetanib

  Contraindicated (1)pentobarbital decreases levels of vandetanib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated. Avoid coadministration with potent CYP3A4 inducers; these drugs reduce exposure to vandetanib by up to 40%.

• vardenafil

  Monitor Closely (1)pentobarbital will decrease the level or effect of vardenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• venetoclax

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of venetoclax by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of venetoclax with strong or moderate CYP3A inducers. Consider alternative treatment with agents that have less CYP3A induction.

• verapamil

  Monitor Closely (1)pentobarbital will decrease the level or effect of verapamil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• vilazodone

  Monitor Closely (1)pentobarbital decreases levels of vilazodone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Consider increasing vilazodone dose up to 2-fold (not to exceed 80 mg/day) when coadministered with strong CYP3A4 inducers for >14 days.

• vinblastine

  Minor (1)pentobarbital will decrease the level or effect of vinblastine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• vincristine

  Minor (1)pentobarbital will decrease the level or effect of vincristine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• vincristine liposomal

  Minor (1)pentobarbital will decrease the level or effect of vincristine liposomal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• vinorelbine

  Minor (1)pentobarbital will decrease the level or effect of vinorelbine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• voclosporin

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of voclosporin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• vonoprazan

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of vonoprazan by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• vorapaxar

  Serious - Use Alternative (1)pentobarbital decreases levels of vorapaxar by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• voriconazole

  Serious - Use Alternative (1)pentobarbital decreases levels of voriconazole by increasing metabolism. Contraindicated.Minor (2)pentobarbital will decrease the level or effect of voriconazole by affecting hepatic enzyme CYP2C19 metabolism. Minor/Significance Unknown.
  
  pentobarbital will decrease the level or effect of voriconazole by affecting hepatic enzyme CYP2C9/10 metabolism. Minor/Significance Unknown.

• vortioxetine

  Monitor Closely (1)pentobarbital increases levels of vortioxetine by increasing metabolism. Modify Therapy/Monitor Closely. Consider increasing the vortioxetine dose when coadministered with strong CYP inducers for >14 days; not to exceed 3 times original vortioxetine dose.

• voxelotor

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of voxelotor by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Voxelotor is primarily metabolized by CYP3A4. Avoid coadministration with moderate or strong CYP3A4 inducers. If unable to avoid coadministration, increase voxelotor dose (see Dosage Modifications).

• warfarin

  Monitor Closely (1)pentobarbital will decrease the level or effect of warfarin by Other (see comment). Use Caution/Monitor. Warfarin's less potent R-enantiomer is metabolized in part by CYP3A4 (and also CYP1A2 and CYP2C19). Monitor INR more frequently if coadministered with inducers of these isoenzymes and adjust warfarin dose if needed.

• xylometazoline

  Monitor Closely (1)pentobarbital increases and xylometazoline decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• yohimbine

  Monitor Closely (1)pentobarbital increases and yohimbine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• zaleplon

  Minor (1)pentobarbital will decrease the level or effect of zaleplon by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• zanubrutinib

  Serious - Use Alternative (1)pentobarbital will decrease the level or effect of zanubrutinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of zanubrutinib (a CYP3A4 substrate) with moderate CYP3A4 inhibitors. If unavoidable, increase zanubrutinib dose to 320 mg PO BID. After discontinuing the CYP3A4 inhibitor, resume previous dose of zanubrutinib.

• ziconotide

  Monitor Closely (1)pentobarbital and ziconotide both increase sedation. Use Caution/Monitor.

• ziprasidone

  Monitor Closely (1)pentobarbital and ziprasidone both increase sedation. Use Caution/Monitor.Minor (1)pentobarbital will decrease the level or effect of ziprasidone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• zolpidem

  Minor (1)pentobarbital will decrease the level or effect of zolpidem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• zonisamide

  Minor (1)pentobarbital will decrease the level or effect of zonisamide by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• zotepine

  Monitor Closely (1)pentobarbital and zotepine both increase sedation. Use Caution/Monitor.