fentanyl transmucosal (Rx)

Breakthrough Cancer Pain

Only for patient already receiving and tolerant to opioid analgesics (ie, >60 mg morphine equivalent/day or 50 mcg transdermal fentanyl/hr)

Abstral

Initial dose: 100 mcg SL

Individually titrate to tolerable dose that provides adequeate analgeisa for breakthrough pain

Not to exceed 2 doses/breakthrough pain episode

Wait at least 2 hr before treating another episode of breakthrough pain

Limit consumption to 4 or fewer breakthrough pain episodes/24 hr

Administer on floor of mouth directly under tongue and allow to completely dissolve

Dose titration

• If adequate analgesia was not obtained with the first 100 mcg dose, continue dose escalation in a stepwise manner over consecutive breakthrough episodes until adequate analgesia with tolerable side effects achieved
• Increase the dose by 100 mcg multiples up to 400 mcg as needed If adequate analgesia is not obtained with a 400 mcg dose, the next titration step is 600 mcg
• If adequate analgesia is not obtained with a 600 mcg dose, the next titration step is 800 mcg
• During titration, patients can be instructed to use multiples of 100 mcg tablets and/or 200 mcg tablets for any single dose
• Instruct patients not to use more than 4 tablets at one time
• If adequate analgesia is not obtained 30 minutes after the use, may repeat the same dose
• Maintenance: Once an appropriate dose for pain management has been established, instruct patients to use only 1 tablet of the appropriate strength per dose

Dose conversion from Actiq

• The initial dose of Abstral is always 100 mcg with the only exception being patients already using Actiq
• For patients being converted from Actiq, instruct patient to stop use of Actiq and dispose of any remaining units
• Initial dose for Abstral when converting from patients taking Actiq:
• -Current Actiq dose = 200 mcg, initial Abstral dose = 100 mcg
• -Current Actiq dose = 400, 600, 800, or 1200 mcg, initial Abstral dose = 200 mcg
• -Current Actiq dose = 1600 mcg, initial Abstral dose = 400 mcg
• Titrating Abstral after converting from Actiq:
• -Converting from Actiq doses ≤400 mcg, initiate titration with 100 mcg Abstral and proceed using multiples of this strength
• -Converting from Actiq doses of 600, 800, or 1200 mcg, initiate titration with 200 mcg Abstral and proceed using multiples of this strength
• -Converting from Actiq doses of 1600 mcg, initiate titration with 400 mcg Abstral and proceed using multiples of this strength

Actiq

200 mcg dissolve in mouth over 15 min period, PRN; wait 15 min before taking next dose

Titrate up to 1600 mcg; limit consumption to <4 units/day

Gradual downward titration for discontinuation

Product substitution

• Substitution of Actiq for any other fentanyl product may result in fatal overdose
• Do not convert on a mcg per mcg basis to Actiq from other fentanyl products
• Do not substitute Actiq prescription for other fentanyl products; pharmacokinetic profile differs substantially and may result in fatal overdose

Fentora

Initial 100 mcg, may redose once after 30 min (place tab between upper cheek and gum till dissolves, any remnant after 30 min may be drunk with water); must wait at least 4 hours before treating another episode of breakthrough pain

Dose titration

• From an initial dose, closely follow patients and change dosage strength until patient reaches a dose that provides adequate analgesia with tolerable side effects Patients should record their use over several episodes of breakthrough pain and discuss their experience with their healthcare provider to determine if a dosage adjustment is warranted
• Patients whose initial dose is 100 mcg and who need to titrate to a higher dose, can be instructed to use two 100 mcg tablets (one on each side of the mouth in the buccal cavity) with their next breakthrough pain episode; if this dosage is not successful, the patient may be instructed to place two 100 mcg tablets on each side of the mouth in the buccal cavity (total of four 100 mcg tablets); titrate using multiples of the 200 mcg FENTORA tablet for doses above 400 mcg (600 mcg and 800 mcg); do not use more than 4 tablets simultaneously
• In cases where the breakthrough pain episode is not relieved after 30 minutes, patients may take ONLY ONE additional dose of same strength for that episode; patients should take a maximum of two doses of this drug for any breakthrough pain episode; during titration, one dose may include administration of 1 to 4 tablets of the same dosage strength (100 mcg or 200 mcg)
• Patients MUST wait at least 4 hours before treating another episode of breakthrough pain with this medication; to reduce risk of overdose during titration, patients should have only one strength of the tablets available at any time
• Patients should be strongly encouraged to use all of their tablets of one strength prior to being prescribed the next strength; if not practical, unused tablets should be disposed of safely; dispose of any unopened tablets remaining from a prescription as soon as they are no longer needed

Dose conversion from Actiq

• Initial 100 mcg if switching from 200-400 mcg Actiq
• Initial 200 mcg if switching from 600-800 mcg Actiq
• Initial 400 mcg if switching from 1200-1600 mcg Actiq

Maintenance dosing

• Once titrated to an effective dose, patients should generally use only 1 tablet of the appropriate strength per breakthrough pain episode
• On occasion when the breakthrough pain episode is not relieved after 30 minutes, patients may take ONLY ONE additional dose using the same strength for that episode
• Must wait at least 4 hours before treating another episode of breakthrough pain
• Once an effective dose is determined using the titration scheme outlined above, an alternate route to buccal administration is sublingual

Onsolis

Initial dose: 200-mcg film placed buccally with breakthrough pain episode

If pain relief not achieved, titrate using multiples of the 200-mcg film (ie, increase dose by 200 mcg in each subsequent episode until adequate pain relief); not to exceed 4 of the 200-mcg films per breakthrough pain episode; do not place films on top of one another, but may place on both sides of mouth

Once pain relief achieved: Treat subsequent breakthrough pain using the determined dose within range of 200-800 mcg

If pain relief not achieved with 800 mcg

• Treat next episode using 1 film containing 1200 mcg; not to exceed 1200 mcg per pain episode
• Separate each dose by at least 2 h, use only once per breakthrough pain episode (do not redose), and limit to 4 or fewer doses daily; if experiencing >4 breakthrough pain episodes per day, consider increasing dose of around-the-clock opioid medication for persistent pain
• Rescue pain medication may be used as directed after 30 min following Onsolis if adequate pain relief not achieved

Administration

• Use tongue to wet inside of cheek or rinse mouth with water to wet area before film placement
• Place pink side of film against inside of cheek and hold in place for 5 seconds
• Avoid consuming liquids for 5 min after film placement
• Do not eat until film dissolves

Subsys

Initial dose is always 100 mcg SL

Individually titrate after initial dose to provide adequate analgesia and minimize side effects

When prescribing, do not switch patients on a mcg per mcg basis from any other oral transmucosal fentanyl product (not equivalent on mcg per mcg with other fentanyl products)

Dose titration

• From the 100 mcg initial dose, closely follow patients and change the dosage level until the patient reaches a dose that provides adequate analgesia using a single dosage per breakthrough cancer pain episode with tolerable side effects; patients should record their use of Subsys over several episodes of breakthrough cancer pain and review their experience with their physicians to determine if a dosage adjustment is warranted
• For each breakthrough pain episode treated, if pain is not relieved after 30 minutes, patients may take only 1 additional dose of the same strength for that episode; thus patients should take a maximum of 2 doses of Subsys for any breakthrough pain episode
• Patients must wait at least 4 hours before treating another episode of breakthrough pain
• If there is a need to titrate to a 200 mcg dose, prescribe 200 mcg Subsys units
• Subsequent titration steps are 400 mcg, 600 mcg, 800 mcg, 1200 mcg and 1600 mcg (see prescribing information)
• To reduce the risk of overdose during titration, patients should have only one strength of Subsys available at any time

Dosing Considerations

Not equivalent on a mcg-per-mcg basis to any other oral transmucosal fentanyl product

Individually titrate to dose providing adequate analgesia with tolerable adverse effects

Only available via special access program

Access to naloxone for opioid overdose

• Assess need for naloxone upon initiating and renewing treatment

• Consider prescribing naloxone

  • Based on patient’s risk factors for overdose (eg, concomitant use of CNS depressants, a history of opioid use disorder, prior opioid overdose); presence of risk factors should not prevent proper pain management
  • Household members (including children) or other close contacts at risk for accidental ingestion or overdose

• Consult patients and caregivers on the following:

  • Availability of naloxone for emergency treatment of opioid overdose
  • Ways differ on how to obtain naloxone as permitted by individual state dispensing and prescribing requirements or guidelines (eg, by prescription, directly from a pharmacist, as part of a community-based program)

Actiq <16 years: Safety and efficacy not established

Abstral; Fentora; Onslis; Subsys <18 years: Safety and efficacy not established

Contraindicated (8)

• alvimopan

  alvimopan, fentanyl transmucosal. receptor binding competition. Contraindicated. Alvimopan is contraindicated in opioid tolerant patients (ie, those who have taken therapeutic doses of opioids for >7 consecutive days immediately prior to taking alvimopan). Patients recently exposed to opioids are expected to be more sensitive to the effects of alvimopan and therefore may experience abdominal pain, nausea and vomiting, and diarrhea. No significant interaction is expected with concurrent use of opioid analgesics and alvimopan in patients who received opioid analgesics for 7 or fewer consecutive days prior to alvimopan.

• isocarboxazid

  isocarboxazid increases toxicity of fentanyl transmucosal by Other (see comment). Contraindicated. Comment: Avoid fentanyl in patients who require concomitant administration MAOIs, or within 14 days of stopping an MAOI. Severe and unpredictable potentiation by MAO inhibitors has been reported with opioid analgesics.

• phenelzine

  phenelzine increases toxicity of fentanyl transmucosal by Other (see comment). Contraindicated. Comment: Avoid fentanyl in patients who require concomitant administration MAOIs, or within 14 days of stopping an MAOI. Severe and unpredictable potentiation by MAO inhibitors has been reported with opioid analgesics.

• rasagiline

  rasagiline increases toxicity of fentanyl transmucosal by Other (see comment). Contraindicated. Comment: Avoid fentanyl in patients who require concomitant administration MAOIs, or within 14 days of stopping an MAOI. Severe and unpredictable potentiation by MAO inhibitors has been reported with opioid analgesics. .

• safinamide

  fentanyl transmucosal, safinamide. Either increases toxicity of the other by serotonin levels. Contraindicated. Concomitant use could result in life-threatening serotonin syndrome.

• selegiline

  selegiline increases toxicity of fentanyl transmucosal by Other (see comment). Contraindicated. Comment: Avoid fentanyl in patients who require concomitant administration MAOIs, or within 14 days of stopping an MAOI. Severe and unpredictable potentiation by MAO inhibitors has been reported with opioid analgesics. .

• selegiline transdermal

  selegiline transdermal increases toxicity of fentanyl transmucosal by Other (see comment). Contraindicated. Comment: Avoid fentanyl in patients who require concomitant administration MAOIs, or within 14 days of stopping an MAOI. Severe and unpredictable potentiation by MAO inhibitors has been reported with opioid analgesics. .

• tranylcypromine

  tranylcypromine increases toxicity of fentanyl transmucosal by Other (see comment). Contraindicated. Comment: Avoid fentanyl in patients who require concomitant administration MAOIs, or within 14 days of stopping an MAOI. Severe and unpredictable potentiation by MAO inhibitors has been reported with opioid analgesics.

Serious - Use Alternative (149)

• acrivastine

  acrivastine and fentanyl transmucosal both increase sedation. Avoid or Use Alternate Drug. Limit use to patients for whom alternative treatment options are inadequate

• amiodarone

  amiodarone will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• amisulpride

  amisulpride and fentanyl transmucosal both increase sedation. Avoid or Use Alternate Drug. Limit use to patients for whom alternative treatment options are inadequate

• amobarbital

  fentanyl transmucosal, amobarbital. 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.
  
  amobarbital will decrease the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. 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

• apalutamide

  apalutamide will decrease the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Coadministration of apalutamide, a strong CYP3A4 inducer, with drugs that are CYP3A4 substrates can result in lower exposure to these medications. Avoid or substitute another drug for these medications when possible. Evaluate for loss of therapeutic effect if medication must be coadministered. Adjust dose according to prescribing information if needed.

• aprepitant

  aprepitant will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• asenapine

  asenapine and fentanyl transmucosal both increase sedation. Avoid or Use Alternate Drug. Limit use to patients for whom alternative treatment options are inadequate

• asenapine transdermal

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

• atazanavir

  atazanavir will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• atracurium

  fentanyl transmucosal, atracurium. 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.

• avapritinib

  avapritinib and fentanyl transmucosal both increase sedation. Avoid or Use Alternate Drug. Limit use to patients for whom alternative treatment options are inadequate

• benzhydrocodone/acetaminophen

  benzhydrocodone/acetaminophen, fentanyl transmucosal. 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 fentanyl transmucosal both increase sedation. Avoid or Use Alternate Drug. Limit use to patients for whom alternative treatment options are inadequate

• bicalutamide

  bicalutamide will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• bremelanotide

  bremelanotide will decrease the level or effect of fentanyl transmucosal by Other (see comment). Avoid or Use Alternate Drug. Bremelanotide may slow gastric emptying and potentially reduces the rate and extent of absorption of concomitantly administered oral medications. Avoid use when taking any oral drug that is dependent on threshold concentrations for efficacy. Interactions listed are representative examples and do not include all possible clinical examples.

• brexpiprazole

  brexpiprazole and fentanyl transmucosal both increase sedation. Avoid or Use Alternate Drug. Limit use to patients for whom alternative treatment options are inadequate

• brigatinib

  brigatinib will decrease the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Brigatinib induces CYP3A4 in vitro. Coadministration with CYP3A4 substrates, particularly those with a narrow therapeutic index, can result in decreased concentrations and loss of efficacy. If unable to avoid coadministration, monitor CYP3A4 substrate levels and adjust dose as needed.

• brimonidine

  brimonidine and fentanyl transmucosal both increase sedation. Avoid or Use Alternate Drug. Limit use to patients for whom alternative treatment options are inadequate

• brivaracetam

  brivaracetam and fentanyl transmucosal both increase sedation. Avoid or Use Alternate Drug. Limit use to patients for whom alternative treatment options are inadequate

• buprenorphine

  fentanyl transmucosal, buprenorphine. 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.
  
  buprenorphine decreases effects of fentanyl transmucosal by pharmacodynamic antagonism. Avoid or Use Alternate Drug. Coadministration of mixed agonist/antagonist and partial agonist opioid analgesics may reduce fentanyl's analgesic effect and possibly precipitate withdrawal symptoms.

• buprenorphine buccal

  buprenorphine buccal decreases effects of fentanyl transmucosal by pharmacodynamic antagonism. Avoid or Use Alternate Drug. Coadministration of mixed agonist/antagonist and partial agonist opioid analgesics may reduce fentanyl's analgesic effect and possibly precipitate withdrawal symptoms.
  
  fentanyl transmucosal, buprenorphine buccal. 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.

• buprenorphine subdermal implant

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

• buprenorphine transdermal

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

• buprenorphine, long-acting injection

  buprenorphine, long-acting injection and fentanyl transmucosal both increase sedation. Avoid or Use Alternate Drug. Limit use to patients for whom alternative treatment options are inadequate

• butabarbital

  fentanyl transmucosal, butabarbital. 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.

• butalbital

  fentanyl transmucosal, butalbital. 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.

• butorphanol

  fentanyl transmucosal, butorphanol. 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.
  
  butorphanol decreases effects of fentanyl transmucosal by pharmacodynamic antagonism. Avoid or Use Alternate Drug. Coadministration of mixed agonist/antagonist and partial agonist opioid analgesics may reduce fentanyl's analgesic effect and possibly precipitate withdrawal symptoms.

• chloral hydrate

  fentanyl transmucosal, chloral hydrate. 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.

• chlorpromazine

  fentanyl transmucosal, chlorpromazine. 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.

• cimetidine

  cimetidine will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• cisatracurium

  fentanyl transmucosal, cisatracurium. 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.

• citalopram

  fentanyl transmucosal, citalopram. Either increases toxicity of the other by serotonin levels. Avoid or Use Alternate Drug.

• clarithromycin

  clarithromycin will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• cobicistat

  cobicistat will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• codeine

  fentanyl transmucosal, codeine. 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.

• conivaptan

  conivaptan will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• crizotinib

  crizotinib will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• cyclosporine

  cyclosporine will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• desflurane

  fentanyl transmucosal, desflurane. 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.

• diazepam intranasal

  diazepam intranasal, fentanyl transmucosal. 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.

• doxycycline

  doxycycline will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• doxylamine

  fentanyl transmucosal, doxylamine. 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.

• dronedarone

  dronedarone will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• eluxadoline

  fentanyl transmucosal, eluxadoline. Either increases effects of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Avoid coadministration with other drugs that cause constipation. Increases risk for constipation related serious adverse reactions. .

• erythromycin base

  erythromycin base will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• erythromycin ethylsuccinate

  erythromycin ethylsuccinate will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• erythromycin lactobionate

  erythromycin lactobionate will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• erythromycin stearate

  erythromycin stearate will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• escitalopram

  fentanyl transmucosal, escitalopram. Either increases toxicity of the other by serotonin levels. Avoid or Use Alternate Drug.

• estazolam

  fentanyl transmucosal, estazolam. 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.

• eszopiclone

  fentanyl transmucosal, eszopiclone. 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.

• ethanol

  fentanyl transmucosal, ethanol. 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.

• etomidate

  fentanyl transmucosal, etomidate. 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.

• etravirine

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

• fexinidazole

  fexinidazole will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Fexinidazole inhibits CYP3A4. Coadministration may increase risk for adverse effects of CYP3A4 substrates.

• fluconazole

  fluconazole will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• fluoxetine

  fentanyl transmucosal, fluoxetine. Either increases toxicity of the other by serotonin levels. Avoid or Use Alternate Drug.

• fluphenazine

  fentanyl transmucosal, fluphenazine. 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.

• flurazepam

  fentanyl transmucosal, flurazepam. 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.

• fluvoxamine

  fluvoxamine and fentanyl transmucosal both increase serotonin levels. Avoid or Use Alternate Drug.

• fosamprenavir

  fosamprenavir will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• fosaprepitant

  fosaprepitant will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• fosphenytoin

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

• grapefruit

  grapefruit will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• haloperidol

  fentanyl transmucosal, haloperidol. 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.
  
  haloperidol will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• hydrocodone

  hydrocodone, fentanyl transmucosal. 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.

• hydromorphone

  fentanyl transmucosal, hydromorphone. 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.

• idelalisib

  idelalisib will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• iloperidone

  iloperidone will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• imatinib

  imatinib will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• indinavir

  indinavir will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• isoflurane

  fentanyl transmucosal, isoflurane. 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.

• isoniazid

  isoniazid will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• itraconazole

  itraconazole will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Not recommended during and 2 weeks after itraconazole. If coadministration with fentanyl is necessary, closely monitor for respiratory depression and sedation and consider fentanyl dose adjustments until stable drug effects are achieved.

• ivosidenib

  ivosidenib will decrease the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of sensitive CYP3A4 substrates with ivosidenib or replace with alternate therapies. If coadministration is unavoidable, monitor patients for loss of therapeutic effect of these drugs.

• ketamine

  fentanyl transmucosal, ketamine. 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.

• lapatinib

  lapatinib will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• levorphanol

  fentanyl transmucosal, levorphanol. 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.

• lidocaine

  lidocaine will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• linezolid

  fentanyl transmucosal, linezolid. Either increases toxicity of the other by serotonin levels. Avoid or Use Alternate Drug.

• lonafarnib

  fentanyl transmucosal will increase the level or effect of lonafarnib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of lonafarnib (a sensitive CYP3A substrate) with weak CYP3A inhibitors is unavoidable, reduce to, or continue lonafarnib at starting dose. Closely monitor for arrhythmias and events (eg, syncope, heart palpitations) since lonafarnib effect on QT interval is unknown.

• loperamide

  fentanyl transmucosal, loperamide. 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.

• lopinavir

  lopinavir will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• loxapine

  fentanyl transmucosal, loxapine. 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.

• loxapine inhaled

  fentanyl transmucosal, loxapine inhaled. 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.

• lumacaftor/ivacaftor

  lumacaftor/ivacaftor will decrease the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Lumacaftor is a strong inducer of CYP3A. Avoid coadministration with sensitive CYP3A substrates or CYP3A substrates with a narrow therapeutic index.

• meperidine

  fentanyl transmucosal, meperidine. 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.

• methadone

  fentanyl transmucosal, methadone. 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.

• methohexital

  fentanyl transmucosal, methohexital. 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.

• metoclopramide intranasal

  fentanyl transmucosal, 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.

• metronidazole

  metronidazole will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• mifepristone

  mifepristone will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Monitor patients for respiratory depression and sedation at frequent intervals if coadministration of CYP3A4 inhibitors with fentanyl is necessary, and consider fentanyl dose adjustments until stable drug effects achieved

• mobocertinib

  mobocertinib will decrease the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If use is unavoidable, increase CYP3A4 substrate dosage in accordance with its prescribing information.

• morphine

  fentanyl transmucosal, morphine. 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.

• nalbuphine

  fentanyl transmucosal, nalbuphine. 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.
  
  nalbuphine decreases effects of fentanyl transmucosal by pharmacodynamic antagonism. Avoid or Use Alternate Drug. Coadministration of mixed agonist/antagonist and partial agonist opioid analgesics may reduce fentanyl's analgesic effect and possibly precipitate withdrawal symptoms.

• nefazodone

  nefazodone will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• nelfinavir

  nelfinavir will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• netupitant/palonosetron

  netupitant/palonosetron will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• nicardipine

  nicardipine will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• olopatadine intranasal

  fentanyl transmucosal 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

  olutasidenib will decrease the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of olutasidenib (a CYP3A4 inducer) with sensitive CYP3A substrates unless otherwise instructed in substrates prescribing information. If unavoidable, monitor for loss of therapeutic effect of sensitive CYP3A4 substrates.

• opium tincture

  fentanyl transmucosal, opium tincture. 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.

• oxycodone

  fentanyl transmucosal, oxycodone. 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.

• oxymorphone

  fentanyl transmucosal, oxymorphone. 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.

• ozanimod

  ozanimod and fentanyl transmucosal both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Avoid or Use Alternate Drug. Because the active metabolite of ozanimod inhibits MAO-B in vitro, there is a potential for serious adverse reactions, including hypertensive crisis. Therefore, coadministration of ozanimod with drugs that can increase norepinephrine or serotonin is not recommended. Monitor for hypertension with concomitant use.

• pancuronium

  fentanyl transmucosal, pancuronium. 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.

• paroxetine

  fentanyl transmucosal, paroxetine. Either increases toxicity of the other by serotonin levels. Avoid or Use Alternate Drug.

• pentazocine

  fentanyl transmucosal, pentazocine. 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.
  
  pentazocine decreases effects of fentanyl transmucosal by pharmacodynamic antagonism. Avoid or Use Alternate Drug. Coadministration of mixed agonist/antagonist and partial agonist opioid analgesics may reduce fentanyl's analgesic effect and possibly precipitate withdrawal symptoms.

• pentobarbital

  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.

• perphenazine

  fentanyl transmucosal, perphenazine. 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.

• pimozide

  fentanyl transmucosal, pimozide. 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.

• posaconazole

  posaconazole will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• prochlorperazine

  fentanyl transmucosal, prochlorperazine. 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.

• propofol

  fentanyl transmucosal, propofol. 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.

• quazepam

  fentanyl transmucosal, quazepam. 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.

• quinidine

  quinidine will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• ramelteon

  fentanyl transmucosal, ramelteon. 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.

• remifentanil

  fentanyl transmucosal, remifentanil. 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.

• ritonavir

  ritonavir will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• rocuronium

  fentanyl transmucosal, rocuronium. 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.

• saquinavir

  saquinavir will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• secobarbital

  fentanyl transmucosal, secobarbital. 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.

• selinexor

  selinexor, fentanyl transmucosal. 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.

• sertraline

  sertraline will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.
  
  fentanyl transmucosal, sertraline. Either increases toxicity of the other by serotonin levels. Avoid or Use Alternate Drug.

• sevoflurane

  fentanyl transmucosal, sevoflurane. 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.

• sotorasib

  sotorasib will decrease the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If use is unavoidable, refer to the prescribing information of the CYP3A4 substrate for dosage modifications

• succinylcholine

  fentanyl transmucosal, succinylcholine. 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.

• sufentanil

  fentanyl transmucosal, sufentanil. 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.

• sufentanil SL

  fentanyl transmucosal, sufentanil SL. 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.
  
  sufentanil SL, fentanyl transmucosal. Either increases toxicity of the other by pharmacodynamic antagonism. 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.
  
  sufentanil SL, fentanyl transmucosal. 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.

• suvorexant

  fentanyl transmucosal, suvorexant. 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.

• tapentadol

  fentanyl transmucosal, tapentadol. 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.

• tasimelteon

  fentanyl transmucosal, tasimelteon. 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.

• temazepam

  fentanyl transmucosal, temazepam. 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.

• tetracycline

  tetracycline will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• thioridazine

  fentanyl transmucosal, thioridazine. 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.

• thiothixene

  fentanyl transmucosal, thiothixene. 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.

• ticagrelor

  ticagrelor will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• tipranavir

  tipranavir will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• tramadol

  fentanyl transmucosal, tramadol. 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.

• triazolam

  fentanyl transmucosal, triazolam. 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.

• trifluoperazine

  fentanyl transmucosal, trifluoperazine. 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.

• valerian

  valerian and fentanyl transmucosal both increase sedation. Avoid or Use Alternate Drug.

• vecuronium

  fentanyl transmucosal, vecuronium. 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.

• verapamil

  verapamil will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• voriconazole

  voriconazole will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• vortioxetine

  fentanyl transmucosal, vortioxetine. Either increases toxicity of the other by serotonin levels. Avoid or Use Alternate Drug.

• voxelotor

  voxelotor will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Voxelotor increases systemic exposure of sensitive CYP3A4 substrates. Avoid coadministration with sensitive CYP3A4 substrates with a narrow therapeutic index. Consider dose reduction of the sensitive CYP3A4 substrate(s) if unable to avoid.

• zaleplon

  fentanyl transmucosal, zaleplon. 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.

• zileuton

  zileuton will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• zolpidem

  fentanyl transmucosal, zolpidem. 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.

Monitor Closely (91)

• amiloride

  fentanyl transmucosal decreases effects of amiloride by Other (see comment). Modify Therapy/Monitor Closely. Comment: Fentanyl can reduce the efficacy of diuretics by inducing antidiuretic hormone release. Fentanyl may also lead to acute urinary retention by causing bladder sphincter spasm (particularly in men with enlarged prostates).

• atogepant

  fentanyl transmucosal will increase the level or effect of atogepant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• atropine

  fentanyl transmucosal, atropine. Either increases toxicity of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of fentanyl with anticholinergics may increase risk for urinary retention and/or severe constipation, which may lead to paralytic ileus.

• belzutifan

  belzutifan will decrease the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. If unable to avoid coadministration of belzutifan with sensitive CYP3A4 substrates, consider increasing the sensitive CYP3A4 substrate dose in accordance with its prescribing information.

• bendroflumethiazide

  fentanyl transmucosal decreases effects of bendroflumethiazide by Other (see comment). Modify Therapy/Monitor Closely. Comment: Fentanyl can reduce the efficacy of diuretics by inducing antidiuretic hormone release. Fentanyl may also lead to acute urinary retention by causing bladder sphincter spasm (particularly in men with enlarged prostates).

• bosentan

  bosentan 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.

• brexanolone

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

• brompheniramine

  fentanyl transmucosal, brompheniramine. Either increases toxicity of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of fentanyl with anticholinergics may increase risk for urinary retention and/or severe constipation, which may lead to paralytic ileus.

• bumetanide

  fentanyl transmucosal decreases effects of bumetanide by Other (see comment). Modify Therapy/Monitor Closely. Comment: Fentanyl can reduce the efficacy of diuretics by inducing antidiuretic hormone release. Fentanyl may also lead to acute urinary retention by causing bladder sphincter spasm (particularly in men with enlarged prostates).

• buprenorphine, long-acting injection

  fentanyl transmucosal 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.

• carbamazepine

  carbamazepine 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.

• carbinoxamine

  fentanyl transmucosal, carbinoxamine. Either increases toxicity of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of fentanyl with anticholinergics may increase risk for urinary retention and/or severe constipation, which may lead to paralytic ileus.

• cenobamate

  cenobamate will decrease the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Increase dose of CYP3A4 substrate, as needed, when coadministered with cenobamate.
  
  cenobamate, fentanyl transmucosal. Either increases effects of the other by sedation. Use Caution/Monitor.

• ceritinib

  ceritinib will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• chloramphenicol

  chloramphenicol will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved

• chlorothiazide

  fentanyl transmucosal decreases effects of chlorothiazide by Other (see comment). Modify Therapy/Monitor Closely. Comment: Fentanyl can reduce the efficacy of diuretics by inducing antidiuretic hormone release. Fentanyl may also lead to acute urinary retention by causing bladder sphincter spasm (particularly in men with enlarged prostates).

• chlorpheniramine

  fentanyl transmucosal, chlorpheniramine. Either increases toxicity of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of fentanyl with anticholinergics may increase risk for urinary retention and/or severe constipation, which may lead to paralytic ileus.

• chlorthalidone

  fentanyl transmucosal decreases effects of chlorthalidone by Other (see comment). Modify Therapy/Monitor Closely. Comment: Fentanyl can reduce the efficacy of diuretics by inducing antidiuretic hormone release. Fentanyl may also lead to acute urinary retention by causing bladder sphincter spasm (particularly in men with enlarged prostates).

• clemastine

  fentanyl transmucosal, clemastine. Either increases toxicity of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of fentanyl with anticholinergics may increase risk for urinary retention and/or severe constipation, which may lead to paralytic ileus.

• cyproheptadine

  fentanyl transmucosal, cyproheptadine. Either increases toxicity of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of fentanyl with anticholinergics may increase risk for urinary retention and/or severe constipation, which may lead to paralytic ileus.

• dabrafenib

  dabrafenib 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.

• daridorexant

  fentanyl transmucosal 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.

• darunavir

  darunavir will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• deutetrabenazine

  fentanyl transmucosal and deutetrabenazine both increase sedation. Use Caution/Monitor.

• dexamethasone

  dexamethasone 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.

• dexchlorpheniramine

  fentanyl transmucosal, dexchlorpheniramine. Either increases toxicity of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of fentanyl with anticholinergics may increase risk for urinary retention and/or severe constipation, which may lead to paralytic ileus.

• dichlorphenamide

  dichlorphenamide and fentanyl transmucosal both decrease serum potassium. Use Caution/Monitor.

• difelikefalin

  difelikefalin and fentanyl transmucosal both increase sedation. Use Caution/Monitor.

• diltiazem

  diltiazem will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• dimenhydrinate

  fentanyl transmucosal, dimenhydrinate. Either increases toxicity of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of fentanyl with anticholinergics may increase risk for urinary retention and/or severe constipation, which may lead to paralytic ileus.

• diphenhydramine

  fentanyl transmucosal, diphenhydramine. Either increases toxicity of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of fentanyl with anticholinergics may increase risk for urinary retention and/or severe constipation, which may lead to paralytic ileus.

• duvelisib

  duvelisib will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Coadministration with duvelisib increases AUC of a sensitive CYP3A4 substrate which may increase the risk of toxicities of these drugs. Consider reducing the dose of the sensitive CYP3A4 substrate and monitor for signs of toxicities of the coadministered sensitive CYP3A substrate.

• efavirenz

  efavirenz 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.

• elagolix

  elagolix decreases levels of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Elagolix is a weak-to-moderate CYP3A4 inducer. Monitor CYP3A substrates if coadministered. Consider increasing CYP3A substrate dose if needed.

• eluxadoline

  eluxadoline increases levels of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Caution when CYP3A substrates that have a narrow therapeutic index are coadministered with eluxadoline.

• encorafenib

  encorafenib, fentanyl transmucosal. affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Encorafenib both inhibits and induces CYP3A4 at clinically relevant plasma concentrations. Coadministration of encorafenib with sensitive CYP3A4 substrates may result in increased toxicity or decreased efficacy of these agents.

• enzalutamide

  enzalutamide 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.

• esketamine intranasal

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

• eslicarbazepine acetate

  eslicarbazepine acetate 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.

• ethacrynic acid

  fentanyl transmucosal decreases effects of ethacrynic acid by Other (see comment). Modify Therapy/Monitor Closely. Comment: Fentanyl can reduce the efficacy of diuretics by inducing antidiuretic hormone release. Fentanyl may also lead to acute urinary retention by causing bladder sphincter spasm (particularly in men with enlarged prostates).

• fedratinib

  fedratinib will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Adjust dose of drugs that are CYP3A4 substrates as necessary.

• finerenone

  fentanyl transmucosal will increase the level or effect of finerenone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Monitor serum potassium during initiation and dosage adjustment of either finererone or weak CYP3A4 inhibitors. Adjust finererone dosage as needed.

• flibanserin

  fentanyl transmucosal and flibanserin both increase sedation. Modify Therapy/Monitor Closely. Risk for sedation increased if flibanserin is coadministration with other CNS depressants.

• furosemide

  fentanyl transmucosal decreases effects of furosemide by Other (see comment). Modify Therapy/Monitor Closely. Comment: Fentanyl can reduce the efficacy of diuretics by inducing antidiuretic hormone release. Fentanyl may also lead to acute urinary retention by causing bladder sphincter spasm (particularly in men with enlarged prostates).

• gabapentin

  gabapentin, fentanyl transmucosal. 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, fentanyl transmucosal. 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

  fentanyl transmucosal and ganaxolone both increase sedation. Use Caution/Monitor.

• guselkumab

  guselkumab, fentanyl transmucosal. Other (see comment). Use Caution/Monitor. Comment: Formation of CYP450 enzymes can be altered by increased levels of certain cytokines during chronic inflammation; thus, normalizing the formation of CYP450 enzymes. Upon initiation or discontinuation of guselkumab in patients who are receiving concomitant CYP450 substrates, particularly those with a narrow therapeutic index, consider monitoring for therapeutic effect.

• hydrochlorothiazide

  fentanyl transmucosal decreases effects of hydrochlorothiazide by Other (see comment). Modify Therapy/Monitor Closely. Comment: Fentanyl can reduce the efficacy of diuretics by inducing antidiuretic hormone release. Fentanyl may also lead to acute urinary retention by causing bladder sphincter spasm (particularly in men with enlarged prostates).

• hydroxyzine

  fentanyl transmucosal, hydroxyzine. Either increases toxicity of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of fentanyl with anticholinergics may increase risk for urinary retention and/or severe constipation, which may lead to paralytic ileus.

• indapamide

  fentanyl transmucosal decreases effects of indapamide by Other (see comment). Modify Therapy/Monitor Closely. Comment: Fentanyl can reduce the efficacy of diuretics by inducing antidiuretic hormone release. Fentanyl may also lead to acute urinary retention by causing bladder sphincter spasm (particularly in men with enlarged prostates).

• isavuconazonium sulfate

  fentanyl transmucosal will increase the level or effect of isavuconazonium sulfate by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
  
  isavuconazonium sulfate will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• istradefylline

  istradefylline will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Istradefylline 40 mg/day increased peak levels and AUC of CYP3A4 substrates in clinical trials. This effect was not observed with istradefylline 20 mg/day. Consider dose reduction of sensitive CYP3A4 substrates.

• ketoconazole

  ketoconazole will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Monitor for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• larotrectinib

  larotrectinib will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved

• lasmiditan

  lasmiditan, fentanyl transmucosal. 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.

• lemborexant

  lemborexant, fentanyl transmucosal. Either increases effects of the other by sedation. Modify Therapy/Monitor Closely. Dosage adjustment may be necessary if lemborexant is coadministered with other CNS depressants because of potentially additive effects.

• levoketoconazole

  levoketoconazole will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Monitor for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• lorlatinib

  lorlatinib will decrease the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. 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

• methyclothiazide

  fentanyl transmucosal decreases effects of methyclothiazide by Other (see comment). Modify Therapy/Monitor Closely. Comment: Fentanyl can reduce the efficacy of diuretics by inducing antidiuretic hormone release. Fentanyl may also lead to acute urinary retention by causing bladder sphincter spasm (particularly in men with enlarged prostates).

• metolazone

  fentanyl transmucosal decreases effects of metolazone by Other (see comment). Modify Therapy/Monitor Closely. Comment: Fentanyl can reduce the efficacy of diuretics by inducing antidiuretic hormone release. Fentanyl may also lead to acute urinary retention by causing bladder sphincter spasm (particularly in men with enlarged prostates).

• midazolam intranasal

  fentanyl transmucosal will increase the level or effect of midazolam intranasal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Coadministration of mild CYP3A4 inhibitors with midazolam intranasal may cause higher midazolam systemic exposure, which may prolong sedation.
  
  midazolam intranasal, fentanyl transmucosal. 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.

• mitotane

  mitotane 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.

• nafcillin

  nafcillin 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.

• nevirapine

  nevirapine 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.

• oliceridine

  oliceridine, fentanyl transmucosal. 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.

• oxcarbazepine

  oxcarbazepine 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.

• pentobarbital

  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.

• phenobarbital

  phenobarbital 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.

• phenytoin

  phenytoin 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.

• pregabalin

  pregabalin, fentanyl transmucosal. 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

  primidone 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.

• promethazine

  fentanyl transmucosal, promethazine. Either increases toxicity of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of fentanyl with anticholinergics may increase risk for urinary retention and/or severe constipation, which may lead to paralytic ileus.

• remimazolam

  remimazolam, fentanyl transmucosal. 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.

• ribociclib

  ribociclib will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Caution if ribociclib is coadministered with sensitive CYP3A4 substrates that have a narrow therapeutic index. Dose reduction for sensitive CYP3A4 substrates may be needed.

• rifabutin

  rifabutin 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.

• rifampin

  rifampin 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.

• rifapentine

  rifapentine 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.

• ropeginterferon alfa 2b

  ropeginterferon alfa 2b will increase the level or effect of fentanyl transmucosal by Other (see comment). Use Caution/Monitor. Certain proinflammatory cytokines, including interferons, can suppress CYP450 enzymes resulting in increased exposures of some CYP substrates. Therefore, monitor patients who are receiving concomitant drugs that are CYP450 substrates with a narrow therapeutic index from toxicities to such drugs.

• rucaparib

  rucaparib will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Adjust dosage of CYP3A4 substrates, if clinically indicated.

• schisandra

  schisandra will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• secobarbital

  secobarbital will decrease the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. 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; May also enhance CNS depressant effect of fentanyl

• spironolactone

  fentanyl transmucosal decreases effects of spironolactone by Other (see comment). Modify Therapy/Monitor Closely. Comment: Fentanyl can reduce the efficacy of diuretics by inducing antidiuretic hormone release. Fentanyl may also lead to acute urinary retention by causing bladder sphincter spasm (particularly in men with enlarged prostates).

• St John's Wort

  St John's Wort 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.

• stiripentol

  stiripentol, fentanyl transmucosal. affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Stiripentol is a CYP3A4 inhibitor and inducer. Monitor CYP3A4 substrates coadministered with stiripentol for increased or decreased effects. CYP3A4 substrates may require dosage adjustment.

• tazemetostat

  tazemetostat will decrease the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
  
  fentanyl transmucosal will increase the level or effect of tazemetostat by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• tecovirimat

  tecovirimat will decrease the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Tecovirimat is a weak CYP3A4 inducer. Monitor sensitive CYP3A4 substrates for effectiveness if coadministered.

• tinidazole

  fentanyl transmucosal will increase the level or effect of tinidazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• torsemide

  fentanyl transmucosal decreases effects of torsemide by Other (see comment). Modify Therapy/Monitor Closely. Comment: Fentanyl can reduce the efficacy of diuretics by inducing antidiuretic hormone release. Fentanyl may also lead to acute urinary retention by causing bladder sphincter spasm (particularly in men with enlarged prostates).

• triamterene

  fentanyl transmucosal decreases effects of triamterene by Other (see comment). Modify Therapy/Monitor Closely. Comment: Fentanyl can reduce the efficacy of diuretics by inducing antidiuretic hormone release. Fentanyl may also lead to acute urinary retention by causing bladder sphincter spasm (particularly in men with enlarged prostates).

• triprolidine

  fentanyl transmucosal, triprolidine. Either increases toxicity of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of fentanyl with anticholinergics may increase risk for urinary retention and/or severe constipation, which may lead to paralytic ileus.

Minor (4)

• acetazolamide

  acetazolamide will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• anastrozole

  anastrozole will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• cyclophosphamide

  cyclophosphamide will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• lenacapavir

  lenacapavir will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown. Carefully monitor the therapeutic effects and adverse reactions associated with CYP3A-metabolized narcotic analgesics (including potentially fatal respiratory depression) is recommended with coadministration.

• acetazolamide

  Minor (1)acetazolamide will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• acrivastine

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

• alvimopan

  Contraindicated (1)alvimopan, fentanyl transmucosal. receptor binding competition. Contraindicated. Alvimopan is contraindicated in opioid tolerant patients (ie, those who have taken therapeutic doses of opioids for >7 consecutive days immediately prior to taking alvimopan). Patients recently exposed to opioids are expected to be more sensitive to the effects of alvimopan and therefore may experience abdominal pain, nausea and vomiting, and diarrhea. No significant interaction is expected with concurrent use of opioid analgesics and alvimopan in patients who received opioid analgesics for 7 or fewer consecutive days prior to alvimopan.

• amiloride

  Monitor Closely (1)fentanyl transmucosal decreases effects of amiloride by Other (see comment). Modify Therapy/Monitor Closely. Comment: Fentanyl can reduce the efficacy of diuretics by inducing antidiuretic hormone release. Fentanyl may also lead to acute urinary retention by causing bladder sphincter spasm (particularly in men with enlarged prostates).

• amiodarone

  Serious - Use Alternative (1)amiodarone will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• amisulpride

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

• amobarbital

  Serious - Use Alternative (2)amobarbital will decrease the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. 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, amobarbital. 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.

• anastrozole

  Minor (1)anastrozole will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• apalutamide

  Serious - Use Alternative (1)apalutamide will decrease the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Coadministration of apalutamide, a strong CYP3A4 inducer, with drugs that are CYP3A4 substrates can result in lower exposure to these medications. Avoid or substitute another drug for these medications when possible. Evaluate for loss of therapeutic effect if medication must be coadministered. Adjust dose according to prescribing information if needed.

• aprepitant

  Serious - Use Alternative (1)aprepitant will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• asenapine

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

• asenapine transdermal

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

• atazanavir

  Serious - Use Alternative (1)atazanavir will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• atogepant

  Monitor Closely (1)fentanyl transmucosal will increase the level or effect of atogepant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• atracurium

  Serious - Use Alternative (1)fentanyl transmucosal, atracurium. 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.

• atropine

  Monitor Closely (1)fentanyl transmucosal, atropine. Either increases toxicity of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of fentanyl with anticholinergics may increase risk for urinary retention and/or severe constipation, which may lead to paralytic ileus.

• avapritinib

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

• belzutifan

  Monitor Closely (1)belzutifan will decrease the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. If unable to avoid coadministration of belzutifan with sensitive CYP3A4 substrates, consider increasing the sensitive CYP3A4 substrate dose in accordance with its prescribing information.

• bendroflumethiazide

  Monitor Closely (1)fentanyl transmucosal decreases effects of bendroflumethiazide by Other (see comment). Modify Therapy/Monitor Closely. Comment: Fentanyl can reduce the efficacy of diuretics by inducing antidiuretic hormone release. Fentanyl may also lead to acute urinary retention by causing bladder sphincter spasm (particularly in men with enlarged prostates).

• benzhydrocodone/acetaminophen

  Serious - Use Alternative (2)benzhydrocodone/acetaminophen, fentanyl transmucosal. 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 fentanyl transmucosal both increase sedation. Avoid or Use Alternate Drug. Limit use to patients for whom alternative treatment options are inadequate

• bicalutamide

  Serious - Use Alternative (1)bicalutamide will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• bosentan

  Monitor Closely (1)bosentan 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.

• bremelanotide

  Serious - Use Alternative (1)bremelanotide will decrease the level or effect of fentanyl transmucosal by Other (see comment). Avoid or Use Alternate Drug. Bremelanotide may slow gastric emptying and potentially reduces the rate and extent of absorption of concomitantly administered oral medications. Avoid use when taking any oral drug that is dependent on threshold concentrations for efficacy. Interactions listed are representative examples and do not include all possible clinical examples.

• brexanolone

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

• brexpiprazole

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

• brigatinib

  Serious - Use Alternative (1)brigatinib will decrease the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Brigatinib induces CYP3A4 in vitro. Coadministration with CYP3A4 substrates, particularly those with a narrow therapeutic index, can result in decreased concentrations and loss of efficacy. If unable to avoid coadministration, monitor CYP3A4 substrate levels and adjust dose as needed.

• brimonidine

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

• brivaracetam

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

• brompheniramine

  Monitor Closely (1)fentanyl transmucosal, brompheniramine. Either increases toxicity of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of fentanyl with anticholinergics may increase risk for urinary retention and/or severe constipation, which may lead to paralytic ileus.

• bumetanide

  Monitor Closely (1)fentanyl transmucosal decreases effects of bumetanide by Other (see comment). Modify Therapy/Monitor Closely. Comment: Fentanyl can reduce the efficacy of diuretics by inducing antidiuretic hormone release. Fentanyl may also lead to acute urinary retention by causing bladder sphincter spasm (particularly in men with enlarged prostates).

• buprenorphine

  Serious - Use Alternative (2)fentanyl transmucosal, buprenorphine. 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.
  
  buprenorphine decreases effects of fentanyl transmucosal by pharmacodynamic antagonism. Avoid or Use Alternate Drug. Coadministration of mixed agonist/antagonist and partial agonist opioid analgesics may reduce fentanyl's analgesic effect and possibly precipitate withdrawal symptoms.

• buprenorphine buccal

  Serious - Use Alternative (2)buprenorphine buccal decreases effects of fentanyl transmucosal by pharmacodynamic antagonism. Avoid or Use Alternate Drug. Coadministration of mixed agonist/antagonist and partial agonist opioid analgesics may reduce fentanyl's analgesic effect and possibly precipitate withdrawal symptoms.
  
  fentanyl transmucosal, buprenorphine buccal. 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.

• buprenorphine subdermal implant

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

• buprenorphine transdermal

  Serious - Use Alternative (2)fentanyl transmucosal, buprenorphine transdermal. 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.
  
  buprenorphine transdermal and fentanyl transmucosal 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 (1)fentanyl transmucosal 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.Serious - Use Alternative (1)buprenorphine, long-acting injection and fentanyl transmucosal both increase sedation. Avoid or Use Alternate Drug. Limit use to patients for whom alternative treatment options are inadequate

• butabarbital

  Serious - Use Alternative (1)fentanyl transmucosal, butabarbital. 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.

• butalbital

  Serious - Use Alternative (1)fentanyl transmucosal, butalbital. 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.

• butorphanol

  Serious - Use Alternative (2)fentanyl transmucosal, butorphanol. 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.
  
  butorphanol decreases effects of fentanyl transmucosal by pharmacodynamic antagonism. Avoid or Use Alternate Drug. Coadministration of mixed agonist/antagonist and partial agonist opioid analgesics may reduce fentanyl's analgesic effect and possibly precipitate withdrawal symptoms.

• carbamazepine

  Monitor Closely (1)carbamazepine 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.

• carbinoxamine

  Monitor Closely (1)fentanyl transmucosal, carbinoxamine. Either increases toxicity of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of fentanyl with anticholinergics may increase risk for urinary retention and/or severe constipation, which may lead to paralytic ileus.

• cenobamate

  Monitor Closely (2)cenobamate, fentanyl transmucosal. Either increases effects of the other by sedation. Use Caution/Monitor.
  
  cenobamate will decrease the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Increase dose of CYP3A4 substrate, as needed, when coadministered with cenobamate.

• ceritinib

  Monitor Closely (1)ceritinib will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• chloral hydrate

  Serious - Use Alternative (1)fentanyl transmucosal, chloral hydrate. 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.

• chloramphenicol

  Monitor Closely (1)chloramphenicol will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved

• chlorothiazide

  Monitor Closely (1)fentanyl transmucosal decreases effects of chlorothiazide by Other (see comment). Modify Therapy/Monitor Closely. Comment: Fentanyl can reduce the efficacy of diuretics by inducing antidiuretic hormone release. Fentanyl may also lead to acute urinary retention by causing bladder sphincter spasm (particularly in men with enlarged prostates).

• chlorpheniramine

  Monitor Closely (1)fentanyl transmucosal, chlorpheniramine. Either increases toxicity of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of fentanyl with anticholinergics may increase risk for urinary retention and/or severe constipation, which may lead to paralytic ileus.

• chlorpromazine

  Serious - Use Alternative (1)fentanyl transmucosal, chlorpromazine. 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.

• chlorthalidone

  Monitor Closely (1)fentanyl transmucosal decreases effects of chlorthalidone by Other (see comment). Modify Therapy/Monitor Closely. Comment: Fentanyl can reduce the efficacy of diuretics by inducing antidiuretic hormone release. Fentanyl may also lead to acute urinary retention by causing bladder sphincter spasm (particularly in men with enlarged prostates).

• cimetidine

  Serious - Use Alternative (1)cimetidine will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• cisatracurium

  Serious - Use Alternative (1)fentanyl transmucosal, cisatracurium. 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.

• citalopram

  Serious - Use Alternative (1)fentanyl transmucosal, citalopram. Either increases toxicity of the other by serotonin levels. Avoid or Use Alternate Drug.

• clarithromycin

  Serious - Use Alternative (1)clarithromycin will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• clemastine

  Monitor Closely (1)fentanyl transmucosal, clemastine. Either increases toxicity of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of fentanyl with anticholinergics may increase risk for urinary retention and/or severe constipation, which may lead to paralytic ileus.

• cobicistat

  Serious - Use Alternative (1)cobicistat will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• codeine

  Serious - Use Alternative (1)fentanyl transmucosal, codeine. 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.

• conivaptan

  Serious - Use Alternative (1)conivaptan will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• crizotinib

  Serious - Use Alternative (1)crizotinib will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• cyclophosphamide

  Minor (1)cyclophosphamide will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• cyclosporine

  Serious - Use Alternative (1)cyclosporine will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• cyproheptadine

  Monitor Closely (1)fentanyl transmucosal, cyproheptadine. Either increases toxicity of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of fentanyl with anticholinergics may increase risk for urinary retention and/or severe constipation, which may lead to paralytic ileus.

• dabrafenib

  Monitor Closely (1)dabrafenib 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.

• daridorexant

  Monitor Closely (1)fentanyl transmucosal 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.

• darunavir

  Monitor Closely (1)darunavir will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• desflurane

  Serious - Use Alternative (1)fentanyl transmucosal, desflurane. 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.

• deutetrabenazine

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

• dexamethasone

  Monitor Closely (1)dexamethasone 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.

• dexchlorpheniramine

  Monitor Closely (1)fentanyl transmucosal, dexchlorpheniramine. Either increases toxicity of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of fentanyl with anticholinergics may increase risk for urinary retention and/or severe constipation, which may lead to paralytic ileus.

• diazepam intranasal

  Serious - Use Alternative (1)diazepam intranasal, fentanyl transmucosal. 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.

• dichlorphenamide

  Monitor Closely (1)dichlorphenamide and fentanyl transmucosal both decrease serum potassium. Use Caution/Monitor.

• difelikefalin

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

• diltiazem

  Monitor Closely (1)diltiazem will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• dimenhydrinate

  Monitor Closely (1)fentanyl transmucosal, dimenhydrinate. Either increases toxicity of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of fentanyl with anticholinergics may increase risk for urinary retention and/or severe constipation, which may lead to paralytic ileus.

• diphenhydramine

  Monitor Closely (1)fentanyl transmucosal, diphenhydramine. Either increases toxicity of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of fentanyl with anticholinergics may increase risk for urinary retention and/or severe constipation, which may lead to paralytic ileus.

• doxycycline

  Serious - Use Alternative (1)doxycycline will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• doxylamine

  Serious - Use Alternative (1)fentanyl transmucosal, doxylamine. 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.

• dronedarone

  Serious - Use Alternative (1)dronedarone will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• duvelisib

  Monitor Closely (1)duvelisib will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Coadministration with duvelisib increases AUC of a sensitive CYP3A4 substrate which may increase the risk of toxicities of these drugs. Consider reducing the dose of the sensitive CYP3A4 substrate and monitor for signs of toxicities of the coadministered sensitive CYP3A substrate.

• efavirenz

  Monitor Closely (1)efavirenz 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.

• elagolix

  Monitor Closely (1)elagolix decreases levels of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Elagolix is a weak-to-moderate CYP3A4 inducer. Monitor CYP3A substrates if coadministered. Consider increasing CYP3A substrate dose if needed.

• eluxadoline

  Monitor Closely (1)eluxadoline increases levels of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Caution when CYP3A substrates that have a narrow therapeutic index are coadministered with eluxadoline.Serious - Use Alternative (1)fentanyl transmucosal, eluxadoline. Either increases effects of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Avoid coadministration with other drugs that cause constipation. Increases risk for constipation related serious adverse reactions. .

• encorafenib

  Monitor Closely (1)encorafenib, fentanyl transmucosal. affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Encorafenib both inhibits and induces CYP3A4 at clinically relevant plasma concentrations. Coadministration of encorafenib with sensitive CYP3A4 substrates may result in increased toxicity or decreased efficacy of these agents.

• enzalutamide

  Monitor Closely (1)enzalutamide 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.

• erythromycin base

  Serious - Use Alternative (1)erythromycin base will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• erythromycin ethylsuccinate

  Serious - Use Alternative (1)erythromycin ethylsuccinate will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• erythromycin lactobionate

  Serious - Use Alternative (1)erythromycin lactobionate will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• erythromycin stearate

  Serious - Use Alternative (1)erythromycin stearate will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• escitalopram

  Serious - Use Alternative (1)fentanyl transmucosal, escitalopram. Either increases toxicity of the other by serotonin levels. Avoid or Use Alternate Drug.

• esketamine intranasal

  Monitor Closely (1)esketamine intranasal, fentanyl transmucosal. Either increases toxicity of the other by sedation. Modify Therapy/Monitor Closely.

• eslicarbazepine acetate

  Monitor Closely (1)eslicarbazepine acetate 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.

• estazolam

  Serious - Use Alternative (1)fentanyl transmucosal, estazolam. 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.

• eszopiclone

  Serious - Use Alternative (1)fentanyl transmucosal, eszopiclone. 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.

• ethacrynic acid

  Monitor Closely (1)fentanyl transmucosal decreases effects of ethacrynic acid by Other (see comment). Modify Therapy/Monitor Closely. Comment: Fentanyl can reduce the efficacy of diuretics by inducing antidiuretic hormone release. Fentanyl may also lead to acute urinary retention by causing bladder sphincter spasm (particularly in men with enlarged prostates).

• ethanol

  Serious - Use Alternative (1)fentanyl transmucosal, ethanol. 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.

• etomidate

  Serious - Use Alternative (1)fentanyl transmucosal, etomidate. 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.

• etravirine

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

• fedratinib

  Monitor Closely (1)fedratinib will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Adjust dose of drugs that are CYP3A4 substrates as necessary.

• fexinidazole

  Serious - Use Alternative (1)fexinidazole will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Fexinidazole inhibits CYP3A4. Coadministration may increase risk for adverse effects of CYP3A4 substrates.

• finerenone

  Monitor Closely (1)fentanyl transmucosal will increase the level or effect of finerenone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Monitor serum potassium during initiation and dosage adjustment of either finererone or weak CYP3A4 inhibitors. Adjust finererone dosage as needed.

• flibanserin

  Monitor Closely (1)fentanyl transmucosal and flibanserin both increase sedation. Modify Therapy/Monitor Closely. Risk for sedation increased if flibanserin is coadministration with other CNS depressants.

• fluconazole

  Serious - Use Alternative (1)fluconazole will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• fluoxetine

  Serious - Use Alternative (1)fentanyl transmucosal, fluoxetine. Either increases toxicity of the other by serotonin levels. Avoid or Use Alternate Drug.

• fluphenazine

  Serious - Use Alternative (1)fentanyl transmucosal, fluphenazine. 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.

• flurazepam

  Serious - Use Alternative (1)fentanyl transmucosal, flurazepam. 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.

• fluvoxamine

  Serious - Use Alternative (1)fluvoxamine and fentanyl transmucosal both increase serotonin levels. Avoid or Use Alternate Drug.

• fosamprenavir

  Serious - Use Alternative (1)fosamprenavir will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• fosaprepitant

  Serious - Use Alternative (1)fosaprepitant will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• fosphenytoin

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

• furosemide

  Monitor Closely (1)fentanyl transmucosal decreases effects of furosemide by Other (see comment). Modify Therapy/Monitor Closely. Comment: Fentanyl can reduce the efficacy of diuretics by inducing antidiuretic hormone release. Fentanyl may also lead to acute urinary retention by causing bladder sphincter spasm (particularly in men with enlarged prostates).

• gabapentin

  Monitor Closely (1)gabapentin, fentanyl transmucosal. 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, fentanyl transmucosal. 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

  Monitor Closely (1)fentanyl transmucosal and ganaxolone both increase sedation. Use Caution/Monitor.

• grapefruit

  Serious - Use Alternative (1)grapefruit will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• guselkumab

  Monitor Closely (1)guselkumab, fentanyl transmucosal. Other (see comment). Use Caution/Monitor. Comment: Formation of CYP450 enzymes can be altered by increased levels of certain cytokines during chronic inflammation; thus, normalizing the formation of CYP450 enzymes. Upon initiation or discontinuation of guselkumab in patients who are receiving concomitant CYP450 substrates, particularly those with a narrow therapeutic index, consider monitoring for therapeutic effect.

• haloperidol

  Serious - Use Alternative (2)fentanyl transmucosal, haloperidol. 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.
  
  haloperidol will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• hydrochlorothiazide

  Monitor Closely (1)fentanyl transmucosal decreases effects of hydrochlorothiazide by Other (see comment). Modify Therapy/Monitor Closely. Comment: Fentanyl can reduce the efficacy of diuretics by inducing antidiuretic hormone release. Fentanyl may also lead to acute urinary retention by causing bladder sphincter spasm (particularly in men with enlarged prostates).

• hydrocodone

  Serious - Use Alternative (1)hydrocodone, fentanyl transmucosal. 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.

• hydromorphone

  Serious - Use Alternative (1)fentanyl transmucosal, hydromorphone. 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.

• hydroxyzine

  Monitor Closely (1)fentanyl transmucosal, hydroxyzine. Either increases toxicity of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of fentanyl with anticholinergics may increase risk for urinary retention and/or severe constipation, which may lead to paralytic ileus.

• idelalisib

  Serious - Use Alternative (1)idelalisib will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• iloperidone

  Serious - Use Alternative (1)iloperidone will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• imatinib

  Serious - Use Alternative (1)imatinib will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• indapamide

  Monitor Closely (1)fentanyl transmucosal decreases effects of indapamide by Other (see comment). Modify Therapy/Monitor Closely. Comment: Fentanyl can reduce the efficacy of diuretics by inducing antidiuretic hormone release. Fentanyl may also lead to acute urinary retention by causing bladder sphincter spasm (particularly in men with enlarged prostates).

• indinavir

  Serious - Use Alternative (1)indinavir will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• isavuconazonium sulfate

  Monitor Closely (2)fentanyl transmucosal will increase the level or effect of isavuconazonium sulfate by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
  
  isavuconazonium sulfate will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• isocarboxazid

  Contraindicated (1)isocarboxazid increases toxicity of fentanyl transmucosal by Other (see comment). Contraindicated. Comment: Avoid fentanyl in patients who require concomitant administration MAOIs, or within 14 days of stopping an MAOI. Severe and unpredictable potentiation by MAO inhibitors has been reported with opioid analgesics.

• isoflurane

  Serious - Use Alternative (1)fentanyl transmucosal, isoflurane. 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.

• isoniazid

  Serious - Use Alternative (1)isoniazid will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• istradefylline

  Monitor Closely (1)istradefylline will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Istradefylline 40 mg/day increased peak levels and AUC of CYP3A4 substrates in clinical trials. This effect was not observed with istradefylline 20 mg/day. Consider dose reduction of sensitive CYP3A4 substrates.

• itraconazole

  Serious - Use Alternative (1)itraconazole will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Not recommended during and 2 weeks after itraconazole. If coadministration with fentanyl is necessary, closely monitor for respiratory depression and sedation and consider fentanyl dose adjustments until stable drug effects are achieved.

• ivosidenib

  Serious - Use Alternative (1)ivosidenib will decrease the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of sensitive CYP3A4 substrates with ivosidenib or replace with alternate therapies. If coadministration is unavoidable, monitor patients for loss of therapeutic effect of these drugs.

• ketamine

  Serious - Use Alternative (1)fentanyl transmucosal, ketamine. 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.

• ketoconazole

  Monitor Closely (1)ketoconazole will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Monitor for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• lapatinib

  Serious - Use Alternative (1)lapatinib will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• larotrectinib

  Monitor Closely (1)larotrectinib will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved

• lasmiditan

  Monitor Closely (1)lasmiditan, fentanyl transmucosal. 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.

• lemborexant

  Monitor Closely (1)lemborexant, fentanyl transmucosal. Either increases effects of the other by sedation. Modify Therapy/Monitor Closely. Dosage adjustment may be necessary if lemborexant is coadministered with other CNS depressants because of potentially additive effects.

• lenacapavir

  Minor (1)lenacapavir will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown. Carefully monitor the therapeutic effects and adverse reactions associated with CYP3A-metabolized narcotic analgesics (including potentially fatal respiratory depression) is recommended with coadministration.

• levoketoconazole

  Monitor Closely (1)levoketoconazole will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Monitor for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• levorphanol

  Serious - Use Alternative (1)fentanyl transmucosal, levorphanol. 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.

• lidocaine

  Serious - Use Alternative (1)lidocaine will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• linezolid

  Serious - Use Alternative (1)fentanyl transmucosal, linezolid. Either increases toxicity of the other by serotonin levels. Avoid or Use Alternate Drug.

• lonafarnib

  Serious - Use Alternative (1)fentanyl transmucosal will increase the level or effect of lonafarnib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of lonafarnib (a sensitive CYP3A substrate) with weak CYP3A inhibitors is unavoidable, reduce to, or continue lonafarnib at starting dose. Closely monitor for arrhythmias and events (eg, syncope, heart palpitations) since lonafarnib effect on QT interval is unknown.

• loperamide

  Serious - Use Alternative (1)fentanyl transmucosal, loperamide. 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.

• lopinavir

  Serious - Use Alternative (1)lopinavir will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• lorlatinib

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

• loxapine

  Serious - Use Alternative (1)fentanyl transmucosal, loxapine. 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.

• loxapine inhaled

  Serious - Use Alternative (1)fentanyl transmucosal, loxapine inhaled. 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.

• lumacaftor/ivacaftor

  Serious - Use Alternative (1)lumacaftor/ivacaftor will decrease the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Lumacaftor is a strong inducer of CYP3A. Avoid coadministration with sensitive CYP3A substrates or CYP3A substrates with a narrow therapeutic index.

• meperidine

  Serious - Use Alternative (1)fentanyl transmucosal, meperidine. 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.

• methadone

  Serious - Use Alternative (1)fentanyl transmucosal, methadone. 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.

• methohexital

  Serious - Use Alternative (1)fentanyl transmucosal, methohexital. 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.

• methyclothiazide

  Monitor Closely (1)fentanyl transmucosal decreases effects of methyclothiazide by Other (see comment). Modify Therapy/Monitor Closely. Comment: Fentanyl can reduce the efficacy of diuretics by inducing antidiuretic hormone release. Fentanyl may also lead to acute urinary retention by causing bladder sphincter spasm (particularly in men with enlarged prostates).

• metoclopramide intranasal

  Serious - Use Alternative (1)fentanyl transmucosal, 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.

• metolazone

  Monitor Closely (1)fentanyl transmucosal decreases effects of metolazone by Other (see comment). Modify Therapy/Monitor Closely. Comment: Fentanyl can reduce the efficacy of diuretics by inducing antidiuretic hormone release. Fentanyl may also lead to acute urinary retention by causing bladder sphincter spasm (particularly in men with enlarged prostates).

• metronidazole

  Serious - Use Alternative (1)metronidazole will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• midazolam intranasal

  Monitor Closely (2)fentanyl transmucosal will increase the level or effect of midazolam intranasal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Coadministration of mild CYP3A4 inhibitors with midazolam intranasal may cause higher midazolam systemic exposure, which may prolong sedation.
  
  midazolam intranasal, fentanyl transmucosal. 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.

• mifepristone

  Serious - Use Alternative (1)mifepristone will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Monitor patients for respiratory depression and sedation at frequent intervals if coadministration of CYP3A4 inhibitors with fentanyl is necessary, and consider fentanyl dose adjustments until stable drug effects achieved

• mitotane

  Monitor Closely (1)mitotane 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.

• mobocertinib

  Serious - Use Alternative (1)mobocertinib will decrease the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If use is unavoidable, increase CYP3A4 substrate dosage in accordance with its prescribing information.

• morphine

  Serious - Use Alternative (1)fentanyl transmucosal, morphine. 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.

• nafcillin

  Monitor Closely (1)nafcillin 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.

• nalbuphine

  Serious - Use Alternative (2)fentanyl transmucosal, nalbuphine. 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.
  
  nalbuphine decreases effects of fentanyl transmucosal by pharmacodynamic antagonism. Avoid or Use Alternate Drug. Coadministration of mixed agonist/antagonist and partial agonist opioid analgesics may reduce fentanyl's analgesic effect and possibly precipitate withdrawal symptoms.

• nefazodone

  Serious - Use Alternative (1)nefazodone will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• nelfinavir

  Serious - Use Alternative (1)nelfinavir will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• netupitant/palonosetron

  Serious - Use Alternative (1)netupitant/palonosetron will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• nevirapine

  Monitor Closely (1)nevirapine 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.

• nicardipine

  Serious - Use Alternative (1)nicardipine will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• oliceridine

  Monitor Closely (1)oliceridine, fentanyl transmucosal. 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)fentanyl transmucosal 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)olutasidenib will decrease the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of olutasidenib (a CYP3A4 inducer) with sensitive CYP3A substrates unless otherwise instructed in substrates prescribing information. If unavoidable, monitor for loss of therapeutic effect of sensitive CYP3A4 substrates.

• opium tincture

  Serious - Use Alternative (1)fentanyl transmucosal, opium tincture. 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.

• oxcarbazepine

  Monitor Closely (1)oxcarbazepine 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.

• oxycodone

  Serious - Use Alternative (1)fentanyl transmucosal, oxycodone. 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.

• oxymorphone

  Serious - Use Alternative (1)fentanyl transmucosal, oxymorphone. 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.

• ozanimod

  Serious - Use Alternative (1)ozanimod and fentanyl transmucosal both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Avoid or Use Alternate Drug. Because the active metabolite of ozanimod inhibits MAO-B in vitro, there is a potential for serious adverse reactions, including hypertensive crisis. Therefore, coadministration of ozanimod with drugs that can increase norepinephrine or serotonin is not recommended. Monitor for hypertension with concomitant use.

• pancuronium

  Serious - Use Alternative (1)fentanyl transmucosal, pancuronium. 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.

• paroxetine

  Serious - Use Alternative (1)fentanyl transmucosal, paroxetine. Either increases toxicity of the other by serotonin levels. Avoid or Use Alternate Drug.

• pentazocine

  Serious - Use Alternative (2)fentanyl transmucosal, pentazocine. 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.
  
  pentazocine decreases effects of fentanyl transmucosal by pharmacodynamic antagonism. Avoid or Use Alternate Drug. Coadministration of mixed agonist/antagonist and partial agonist opioid analgesics may reduce fentanyl's analgesic effect and possibly precipitate withdrawal symptoms.

• pentobarbital

  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.

• perphenazine

  Serious - Use Alternative (1)fentanyl transmucosal, perphenazine. 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.

• phenelzine

  Contraindicated (1)phenelzine increases toxicity of fentanyl transmucosal by Other (see comment). Contraindicated. Comment: Avoid fentanyl in patients who require concomitant administration MAOIs, or within 14 days of stopping an MAOI. Severe and unpredictable potentiation by MAO inhibitors has been reported with opioid analgesics.

• phenobarbital

  Monitor Closely (1)phenobarbital 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.

• phenytoin

  Monitor Closely (1)phenytoin 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.

• pimozide

  Serious - Use Alternative (1)fentanyl transmucosal, pimozide. 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.

• posaconazole

  Serious - Use Alternative (1)posaconazole will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• pregabalin

  Monitor Closely (1)pregabalin, fentanyl transmucosal. 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

  Monitor Closely (1)primidone 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.

• prochlorperazine

  Serious - Use Alternative (1)fentanyl transmucosal, prochlorperazine. 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.

• promethazine

  Monitor Closely (1)fentanyl transmucosal, promethazine. Either increases toxicity of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of fentanyl with anticholinergics may increase risk for urinary retention and/or severe constipation, which may lead to paralytic ileus.

• propofol

  Serious - Use Alternative (1)fentanyl transmucosal, propofol. 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.

• quazepam

  Serious - Use Alternative (1)fentanyl transmucosal, quazepam. 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.

• quinidine

  Serious - Use Alternative (1)quinidine will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• ramelteon

  Serious - Use Alternative (1)fentanyl transmucosal, ramelteon. 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.

• rasagiline

  Contraindicated (1)rasagiline increases toxicity of fentanyl transmucosal by Other (see comment). Contraindicated. Comment: Avoid fentanyl in patients who require concomitant administration MAOIs, or within 14 days of stopping an MAOI. Severe and unpredictable potentiation by MAO inhibitors has been reported with opioid analgesics. .

• remifentanil

  Serious - Use Alternative (1)fentanyl transmucosal, remifentanil. 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.

• remimazolam

  Monitor Closely (1)remimazolam, fentanyl transmucosal. 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.

• ribociclib

  Monitor Closely (1)ribociclib will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Caution if ribociclib is coadministered with sensitive CYP3A4 substrates that have a narrow therapeutic index. Dose reduction for sensitive CYP3A4 substrates may be needed.

• rifabutin

  Monitor Closely (1)rifabutin 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.

• rifampin

  Monitor Closely (1)rifampin 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.

• rifapentine

  Monitor Closely (1)rifapentine 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.

• ritonavir

  Serious - Use Alternative (1)ritonavir will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• rocuronium

  Serious - Use Alternative (1)fentanyl transmucosal, rocuronium. 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.

• ropeginterferon alfa 2b

  Monitor Closely (1)ropeginterferon alfa 2b will increase the level or effect of fentanyl transmucosal by Other (see comment). Use Caution/Monitor. Certain proinflammatory cytokines, including interferons, can suppress CYP450 enzymes resulting in increased exposures of some CYP substrates. Therefore, monitor patients who are receiving concomitant drugs that are CYP450 substrates with a narrow therapeutic index from toxicities to such drugs.

• rucaparib

  Monitor Closely (1)rucaparib will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Adjust dosage of CYP3A4 substrates, if clinically indicated.

• safinamide

  Contraindicated (1)fentanyl transmucosal, safinamide. Either increases toxicity of the other by serotonin levels. Contraindicated. Concomitant use could result in life-threatening serotonin syndrome.

• saquinavir

  Serious - Use Alternative (1)saquinavir will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• schisandra

  Monitor Closely (1)schisandra will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• secobarbital

  Monitor Closely (1)secobarbital will decrease the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. 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; May also enhance CNS depressant effect of fentanylSerious - Use Alternative (1)fentanyl transmucosal, secobarbital. 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.

• selegiline

  Contraindicated (1)selegiline increases toxicity of fentanyl transmucosal by Other (see comment). Contraindicated. Comment: Avoid fentanyl in patients who require concomitant administration MAOIs, or within 14 days of stopping an MAOI. Severe and unpredictable potentiation by MAO inhibitors has been reported with opioid analgesics. .

• selegiline transdermal

  Contraindicated (1)selegiline transdermal increases toxicity of fentanyl transmucosal by Other (see comment). Contraindicated. Comment: Avoid fentanyl in patients who require concomitant administration MAOIs, or within 14 days of stopping an MAOI. Severe and unpredictable potentiation by MAO inhibitors has been reported with opioid analgesics. .

• selinexor

  Serious - Use Alternative (1)selinexor, fentanyl transmucosal. 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.

• sertraline

  Serious - Use Alternative (2)fentanyl transmucosal, sertraline. Either increases toxicity of the other by serotonin levels. Avoid or Use Alternate Drug.
  
  sertraline will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• sevoflurane

  Serious - Use Alternative (1)fentanyl transmucosal, sevoflurane. 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.

• sotorasib

  Serious - Use Alternative (1)sotorasib will decrease the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If use is unavoidable, refer to the prescribing information of the CYP3A4 substrate for dosage modifications

• spironolactone

  Monitor Closely (1)fentanyl transmucosal decreases effects of spironolactone by Other (see comment). Modify Therapy/Monitor Closely. Comment: Fentanyl can reduce the efficacy of diuretics by inducing antidiuretic hormone release. Fentanyl may also lead to acute urinary retention by causing bladder sphincter spasm (particularly in men with enlarged prostates).

• St John's Wort

  Monitor Closely (1)St John's Wort 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.

• stiripentol

  Monitor Closely (1)stiripentol, fentanyl transmucosal. affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Stiripentol is a CYP3A4 inhibitor and inducer. Monitor CYP3A4 substrates coadministered with stiripentol for increased or decreased effects. CYP3A4 substrates may require dosage adjustment.

• succinylcholine

  Serious - Use Alternative (1)fentanyl transmucosal, succinylcholine. 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.

• sufentanil

  Serious - Use Alternative (1)fentanyl transmucosal, sufentanil. 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.

• sufentanil SL

  Serious - Use Alternative (3)sufentanil SL, fentanyl transmucosal. Either increases toxicity of the other by pharmacodynamic antagonism. 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.
  
  sufentanil SL, fentanyl transmucosal. 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.
  
  fentanyl transmucosal, sufentanil SL. 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.

• suvorexant

  Serious - Use Alternative (1)fentanyl transmucosal, suvorexant. 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.

• tapentadol

  Serious - Use Alternative (1)fentanyl transmucosal, tapentadol. 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.

• tasimelteon

  Serious - Use Alternative (1)fentanyl transmucosal, tasimelteon. 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.

• tazemetostat

  Monitor Closely (2)tazemetostat will decrease the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
  
  fentanyl transmucosal will increase the level or effect of tazemetostat by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• tecovirimat

  Monitor Closely (1)tecovirimat will decrease the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Tecovirimat is a weak CYP3A4 inducer. Monitor sensitive CYP3A4 substrates for effectiveness if coadministered.

• temazepam

  Serious - Use Alternative (1)fentanyl transmucosal, temazepam. 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.

• tetracycline

  Serious - Use Alternative (1)tetracycline will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• thioridazine

  Serious - Use Alternative (1)fentanyl transmucosal, thioridazine. 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.

• thiothixene

  Serious - Use Alternative (1)fentanyl transmucosal, thiothixene. 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.

• ticagrelor

  Serious - Use Alternative (1)ticagrelor will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• tinidazole

  Monitor Closely (1)fentanyl transmucosal will increase the level or effect of tinidazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• tipranavir

  Serious - Use Alternative (1)tipranavir will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• torsemide

  Monitor Closely (1)fentanyl transmucosal decreases effects of torsemide by Other (see comment). Modify Therapy/Monitor Closely. Comment: Fentanyl can reduce the efficacy of diuretics by inducing antidiuretic hormone release. Fentanyl may also lead to acute urinary retention by causing bladder sphincter spasm (particularly in men with enlarged prostates).

• tramadol

  Serious - Use Alternative (1)fentanyl transmucosal, tramadol. 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.

• tranylcypromine

  Contraindicated (1)tranylcypromine increases toxicity of fentanyl transmucosal by Other (see comment). Contraindicated. Comment: Avoid fentanyl in patients who require concomitant administration MAOIs, or within 14 days of stopping an MAOI. Severe and unpredictable potentiation by MAO inhibitors has been reported with opioid analgesics.

• triamterene

  Monitor Closely (1)fentanyl transmucosal decreases effects of triamterene by Other (see comment). Modify Therapy/Monitor Closely. Comment: Fentanyl can reduce the efficacy of diuretics by inducing antidiuretic hormone release. Fentanyl may also lead to acute urinary retention by causing bladder sphincter spasm (particularly in men with enlarged prostates).

• triazolam

  Serious - Use Alternative (1)fentanyl transmucosal, triazolam. 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.

• trifluoperazine

  Serious - Use Alternative (1)fentanyl transmucosal, trifluoperazine. 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.

• triprolidine

  Monitor Closely (1)fentanyl transmucosal, triprolidine. Either increases toxicity of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of fentanyl with anticholinergics may increase risk for urinary retention and/or severe constipation, which may lead to paralytic ileus.

• valerian

  Serious - Use Alternative (1)valerian and fentanyl transmucosal both increase sedation. Avoid or Use Alternate Drug.

• vecuronium

  Serious - Use Alternative (1)fentanyl transmucosal, vecuronium. 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.

• verapamil

  Serious - Use Alternative (1)verapamil will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• voriconazole

  Serious - Use Alternative (1)voriconazole will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• vortioxetine

  Serious - Use Alternative (1)fentanyl transmucosal, vortioxetine. Either increases toxicity of the other by serotonin levels. Avoid or Use Alternate Drug.

• voxelotor

  Serious - Use Alternative (1)voxelotor will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Voxelotor increases systemic exposure of sensitive CYP3A4 substrates. Avoid coadministration with sensitive CYP3A4 substrates with a narrow therapeutic index. Consider dose reduction of the sensitive CYP3A4 substrate(s) if unable to avoid.

• zaleplon

  Serious - Use Alternative (1)fentanyl transmucosal, zaleplon. 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.

• zileuton

  Serious - Use Alternative (1)zileuton will increase the level or effect of fentanyl transmucosal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of CYP3A4 inhibitors with fentanyl is necessary, monitor patients for respiratory depression and sedation at frequent intervals and consider fentanyl dose adjustments until stable drug effects are achieved.

• zolpidem

  Serious - Use Alternative (1)fentanyl transmucosal, zolpidem. 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.