Dosing & Uses
Dosage Forms & Strengths
capsule/tablet, extended release
- 120mg
- 180mg
- 240mg
- 300mg
- 360mg
- 420mg
injectable solution
- 5mg/mL
powder for injection
- 100mg
tablet
- 30mg
- 60mg
- 90mg
- 120mg
Angina
Conventional: 30 mg PO q6hr; increased every 1 or 2 days until angina controlled (usually 180-360 mg/day PO divided q6-8hr); not to exceed 360 mg/day
Cardizem CD, Cartia XT, Dilt-CD: 120-180 mg/day PO; titrate over 7-14 days; maintenance range usually 120-320 mg/day; not to exceed 480 mg/day
DilacorXR, Dilt-XR: 120 mg/day PO; titrate after 7-14 days; maintenance range usually 120-320 mg/day; not to exceed 540 mg/day
Tiazac, Taztia XT: 120-180 mg/day PO; titrate after 7-14 days; maintenance range usually 120-320 mg/day; not to exceed 540 mg/day
Cardizem LA, Matzim LA: 180 mg/day PO; titrate after 14 days; maintenance range usually 120-320 mg/day; not to exceed 360 mg/day
Hypertension
Cardizem CD, Cartia XT, Dilt-CD: 180-240 mg/day PO; titrate after 14 days; maintenance range usually 180-420 mg/day; not to exceed 480 mg/day
Dilacor XR, Dilt-XR: 180-240 mg/day PO; titrate after 14 days; maintenance range usually 180-420 mg/day; not to exceed 540 mg/day
Tiazac, Taztia XT: 120-240 mg/day PO; titrate after 14 days; maintenance range usually 180-420 mg/day; not to exceed 540 mg/day
Cardizem LA, Matzim LA: 180-240 mg/day PO; titrate after 14 days; maintenance range usually 120-540 mg/day
Extended-release twice-daily dosing: 60-120 mg PO q12hr; may be adjusted after 14 days; maintenance range usually 240-360 mg/day
Paroxysmal Supraventricular Tachycardia
0.25 mg/kg (average adult dose, 20 mg) direct IV over 2 minutes; after 15 minutes, may repeat bolus by administering 0.35 mg/kg actual body weight over 2 min (average adult dose, 25 mg) direct IV if first dose tolerated but response inadequate; some clinicians suggest additional doses q15min
Use weight-based dosing for lower-body-weight patients
Continuous infusion: 10 mg/hr IV initially; increased to no more than 15 mg/hr for up to 24 hours
Atrial Fibrillation/Flutter
0.25 mg/kg (usual adult dose, 20 mg) direct IV over 2 minutes; after 15 minutes, may repeat bolus by administering 0.35 mg/kg actual body weight over 2 min (average adult dose, 25 mg) direct IV if first dose tolerated but response inadequate; some clinicians suggest additional doses q15min
Use weight-based dosing for lower-body-weight patients
Continuous infusion: 10 mg/hr IV initially; increased to no more than 15 mg/hr for up to 24 hours
Dose Modifications
Renal Impairment
- Use caution; not studied
Hepatic Impairment
- Use caution; not studied
Interactions
Interaction Checker
No Results

Contraindicated
Serious - Use Alternative
Significant - Monitor Closely
Minor

Contraindicated (5)
- dantrolene
dantrolene, diltiazem. Either increases toxicity of the other by Mechanism: pharmacodynamic synergism. Contraindicated. Rare incidence of cardiovascular collapse and marked hyperkalemia observed when coadministered; may be higher risk with nondihydropyridine calcium channel blockers.
- flibanserin
diltiazem will increase the level or effect of flibanserin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated. Coadministration of flibanserin with moderate or strong CYP3A4 inhibitors is contraindicated. Severe hypotension or syncope can occur.
- lomitapide
diltiazem increases levels of lomitapide by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated. Increases lomitapide levels several folds.
- lonafarnib
diltiazem will increase the level or effect of lonafarnib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated. Lonafarnib is a sensitive CYP3A4 substrate. Coadministration with strong or moderate CYP3A4 inhibitors is contraindicated.
- pimozide
diltiazem will increase the level or effect of pimozide by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated. Coadministration with potent CYP3A4 inhibitors may significantly increase the plasma concentrations of pimozide and may potentiate the risk of ventricular arrhythmias (eg, ventricular tachycardia, torsade de pointes, cardiac arrest, sudden death).
Serious - Use Alternative (81)
- amlodipine
diltiazem will increase the level or effect of amlodipine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Concomitant use with amlodipine and diltiazem reported an a 60% increase in amlodipine AUC. Monitor increased effects and toxicities (eg, bradycardia, sinus arrest, decreased cardiac output) if amiodarone is concomitantly used with nondihydropyridine calcium channel blocker (ie, diltiazem).
- apalutamide
apalutamide will decrease the level or effect of diltiazem 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
diltiazem will increase the level or effect of aprepitant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Moderate CYP3A4 inhibitors may increase serum concentrations and/or toxicities of aprepitant.
- atenolol
diltiazem, atenolol. Either increases toxicity of the other by unspecified interaction mechanism. Avoid or Use Alternate Drug. Can increase risk of bradycardia.
- avapritinib
diltiazem will increase the level or effect of avapritinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of avapritinib with moderate CYP3A4 inhibitors. If unable to avoid, reduce avapritinib starting dose. See drug monograph Dosage Modifications.
- betaxolol
diltiazem, betaxolol. Either increases toxicity of the other by unspecified interaction mechanism. Avoid or Use Alternate Drug. Can increase risk of bradycardia.
- bisoprolol
diltiazem, bisoprolol. Either increases toxicity of the other by unspecified interaction mechanism. Avoid or Use Alternate Drug. Can increase risk of bradycardia.
- bosutinib
diltiazem increases levels of bosutinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.
- budesonide
diltiazem will increase the level or effect of budesonide by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid concomitant use of CYP3A4 inhibitors and oral budesonide. If coadministration is necessary, closely monitor for signs and symptoms of corticosteroid excess.
- ceritinib
ceritinib will increase the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.
- clonidine
clonidine, diltiazem. unknown mechanism. Avoid or Use Alternate Drug. Reports of sinus bradycardia resulting in hospitalization and pacemaker insertion reported with concomitant use. Possible life-threatening effect, monitor closely.
- cobimetinib
diltiazem will increase the level or effect of cobimetinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If concurrent short term (=14 days) use of moderate CYP3A inhibitors is unavoidable for patients who are taking cobimetinib 60 mg, reduce cobimetinib dose to 20 mg. After discontinuing the moderate CYP3A inhibitor, resume cobimetinib 60 mg. In patients who are already receiving reduced cobimetinib doses due to adverse reactions, avoid moderate CYP3A4 and use alternative therapy.
- colchicine
diltiazem will increase the level or effect of colchicine by Other (see comment). Avoid or Use Alternate Drug. Colchicine is a P-gp and CYP3A4 substrate. Avoid use with drugs that are both P-gp and strong CYP3A4 inhibitors. If coadministration is necessary, decrease colchicine dose or frequency as recommended in prescribing information. Use of any colchicine product in conjunction with strong CYP3A4 inhibitors is contraindicated in patients with renal or hepatic impairment.
- copanlisib
diltiazem will increase the level or effect of copanlisib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Monitor patients for increased copanlisib effects/toxicities if coadministered with diltiazem. Consider reducing copanlisib dose to 45 mg.
- dihydroergotamine
diltiazem will increase the level or effect of dihydroergotamine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.
- dihydroergotamine intranasal
diltiazem will increase the level or effect of dihydroergotamine intranasal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.
- dronedarone
diltiazem will increase the level or effect of dronedarone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Use lower starting doses of nondihydropyridine calcium channel blockers (eg,l, diltiazem). Consider increasing calcium channel blocker dose after combination is being well-tolerated.
- elacestrant
diltiazem will increase the level or effect of elacestrant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.
- eletriptan
diltiazem will increase the level or effect of eletriptan by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid concomitantly use of eletriptan and moderate CYP3A4 inhibitors for 72 hours.
- eliglustat
diltiazem increases levels of eliglustat by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Moderate CYP3A4 inhibitors are not recommended with eliglustat poor or intermediate metabolizers; reduce eliglustat dose from 84 mg BID to 84 mg once daily in extensive metabolizers .
- encorafenib
diltiazem will increase the level or effect of encorafenib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If concomitant use of a moderate CYP3A4 inhibitor is unavoidable, reduce encorafenib dose to one-half of the dose (eg, reduce from 450 mg/day to 225 mg/day). After discontinuing the inhibitor for 3-5 elimination half-lives, resume previous encorafenib dose.
- entrectinib
diltiazem will increase the level or effect of entrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of moderate CYP3A4 inhibitors with entrectinib, a CYP3A4 substrate. If coadministration unavoidable, reduce dose to 200 mg/day for patients aged 12 y or older with BSA >1.50m2. Resume previous entrectinib dose after discontinuing moderate CYP3A inhibitor for 3-5 elimination half-lives.
- enzalutamide
enzalutamide will decrease the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.
- eplerenone
diltiazem will increase the level or effect of eplerenone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Coadministration of eplerenone and mdoerate CYP3A4 inhibitor is not recommended. If combination is unavoidable, eplerenone dose should not exceed 25 mg/day for patients with congestive heart failure following MI.
- erdafitinib
erdafitinib will increase the level or effect of diltiazem by P-glycoprotein (MDR1) efflux transporter. Avoid or Use Alternate Drug. If coadministration unavoidable, separate administration by at least 6 hr before or after administration of P-gp substrates with narrow therapeutic index.
- erythromycin base
diltiazem will increase the level or effect of erythromycin base by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.
erythromycin base will increase the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Consider an alternative to erythromycin in patients receiving diltiazem. If no alternative is available, monitor for the effects of diltiazem following erythromycin initiation/discontinuation. - erythromycin ethylsuccinate
erythromycin ethylsuccinate will increase the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Consider an alternative to erythromycin in patients receiving diltiazem. If no alternative is available, monitor for the effects of diltiazem following erythromycin initiation/discontinuation.
diltiazem will increase the level or effect of erythromycin ethylsuccinate by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. - erythromycin lactobionate
erythromycin lactobionate will increase the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Consider an alternative to erythromycin in patients receiving diltiazem. If no alternative is available, monitor for the effects of diltiazem following erythromycin initiation/discontinuation.
diltiazem will increase the level or effect of erythromycin lactobionate by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. - erythromycin stearate
erythromycin stearate will increase the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Consider an alternative to erythromycin in patients receiving diltiazem. If no alternative is available, monitor for the effects of diltiazem following erythromycin initiation/discontinuation.
diltiazem will increase the level or effect of erythromycin stearate by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. - esmolol
diltiazem, esmolol. Either increases toxicity of the other by unspecified interaction mechanism. Avoid or Use Alternate Drug. Can increase risk of bradycardia.
- fexinidazole
fexinidazole will increase the level or effect of diltiazem 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.
- fosaprepitant
diltiazem will increase the level or effect of fosaprepitant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Moderate CYP3A4 inhibitors may increase serum concentrations and/or toxicities of aprepitant.
- ibrutinib
diltiazem increases levels of ibrutinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Coadministration with moderate CYP3A4 inhibitors, reduce ibrutinib dose to 280 mg qDay (B-cell malignancies) or 420 mg qDay (graft versus host disease). After CYP3A inhibitor discontinuation, resume previous dose of ibrutinib.
- idelalisib
idelalisib will increase the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Idelalisib is a strong CYP3A inhibitor; avoid coadministration with sensitive CYP3A substrates
- indinavir
indinavir will increase the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.
- infigratinib
diltiazem will increase the level or effect of infigratinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.
- ivabradine
diltiazem will increase the level or effect of ivabradine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of ivabradine with moderate CYP3A4 inhibitors.
diltiazem, ivabradine. Either increases effects of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Most patients receiving ivabradine will also be treated with a beta-blocker. The risk of bradycardia increases with coadministration of drugs that slow heart rate (eg, digoxin, amiodarone, beta-blockers). Monitor heart rate in patients taking ivabradine with other negative chronotropes. - ivosidenib
diltiazem will increase the level or effect of ivosidenib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Coadministration with moderate CYP3A4 inhibitors may increase ivosidenib plasma concentrations, thus increasing the risk of QTc prolongation. Monitor for increased risk of QTc interval prolongation.
ivosidenib will decrease the level or effect of diltiazem 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. - lasmiditan
lasmiditan increases levels of diltiazem by P-glycoprotein (MDR1) efflux transporter. Avoid or Use Alternate Drug.
- lemborexant
diltiazem will increase the level or effect of lemborexant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of lemborexant with moderate or strong CYP3A inhibitors.
- levobunolol
diltiazem, levobunolol. Either increases toxicity of the other by unspecified interaction mechanism. Avoid or Use Alternate Drug. Can increase risk of bradycardia.
- lofexidine
lofexidine, diltiazem. Either increases effects of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Avoid coadministration with other drugs that decrease pulse or blood pressure to mitigate risk of excessive bradycardia and hypotension.
- lopinavir
lopinavir will increase the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.
- lorlatinib
lorlatinib will decrease the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.
- lovastatin
diltiazem will increase the level or effect of lovastatin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Do not exceed 20 mg/day of lovastatin
- lurbinectedin
diltiazem will increase the level or effect of lurbinectedin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.
- mavacamten
diltiazem, mavacamten. Either increases effects of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Expect additive negative inotropic effects of mavacamten and other drugs that reduce cardiac contractility.
- metoprolol
diltiazem, metoprolol. Either increases toxicity of the other by unspecified interaction mechanism. Avoid or Use Alternate Drug. Can increase risk of bradycardia.
- midazolam intranasal
diltiazem will increase the level or effect of midazolam intranasal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Coadministration of moderate CYP3A4 inhibitors with midazolam intranasal causes higher midazolam systemic exposure, which may prolong sedation.
- midostaurin
diltiazem will increase the level or effect of midostaurin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration with strong CYP3A4 inhibitors cannot be avoided, monitor midostaurin for increased risk of adverse reactions, especially during the first week of treatment.
- mobocertinib
diltiazem will increase the level or effect of mobocertinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If use of moderate CYP3A4 inhibitor unavoidable, reduce mobocertinib dose by ~50% (eg, 160 to 80 mg); closely monitor QTc interval.
- nadolol
diltiazem, nadolol. Either increases toxicity of the other by unspecified interaction mechanism. Avoid or Use Alternate Drug. Can increase risk of bradycardia.
- naloxegol
diltiazem will increase the level or effect of naloxegol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministation of naloxegol with moderate CYP3A4 inhibitors is unavoidable, reduce naloxegol dose to 12.5 mg qDay
- nebivolol
diltiazem, nebivolol. Either increases toxicity of the other by unspecified interaction mechanism. Avoid or Use Alternate Drug. Can increase risk of bradycardia.
- neratinib
diltiazem will increase the level or effect of neratinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of neratinib with strong/moderate CYP3A4 inhibitors.
- olaparib
diltiazem will increase the level or effect of olaparib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration with moderate CYP3A inhibitors cannot be avoided, reduce olaparib dose to 200 mg (capsule) or 150 mg (tablet) PO BID. Do not substitute tablets with capsules.
- omaveloxolone
diltiazem will increase the level or effect of omaveloxolone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If unavoidable, reduce omaveloxolone dose to 100 mg/day. Closely monitor for adverse effects. If adverse effects emerge, further reduce to 50 mg/day.
- pacritinib
diltiazem will increase the level or effect of pacritinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.
- pemigatinib
diltiazem will increase the level or effect of pemigatinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration with strong or moderate CYP3A4 inhibitors is unavoidable, reduce pemigatinib dose (refer to drug monograph dosage modifications). After discontinuing the CYP3A4 inhibitor for 3 elimination half-lives, may resume previous pemigatinib dose.
- pexidartinib
diltiazem will increase the level or effect of pexidartinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration with strong or moderate CYP3A4 inhibitors is unavoidable, reduce pexidartinib dose (refer to drug monograph dosage modifications). After discontinuing the CYP3A4 inhibitor for 3 elimination half-lives, may resume previous pexidartinib dose.
- ponesimod
ponesimod, diltiazem. Either increases effects of the other by QTc interval. Avoid or Use Alternate Drug. Consult cardiologist if considering treatment. Generally, should not be initiated in patients who are concurrently taking QT prolonging drugs with known arrhythmogenic properties, such as HR-lowering calcium channel blockers (eg, verapamil, diltiazem).
- primidone
primidone will decrease the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.
- propafenone
diltiazem will increase the level or effect of propafenone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of diltiazem with pimozide may increase the serum concentration of pimozide (eg, ventricular tachycardia, torsade de pointes, cardiac arrest, sudden death).
- propranolol
diltiazem, propranolol. Either increases toxicity of the other by unspecified interaction mechanism. Avoid or Use Alternate Drug. Can increase risk of bradycardia.
- repotrectinib
diltiazem will increase the level or effect of repotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Discontinue strong or moderate CYP3A inhibitors and wait 3-5 elimination half-lives before initiating repotrectinib.
- rifampin
rifampin will decrease the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration with diltiazem and strong CYP3A4 inducers However, if concomitant use is necessary, consider dosage adjustment and close monitoring of pharmacologic effects (eg, blood pressure) whenever a strong CYP3A4 inducer is added to or discontinued from therapy.
- selumetinib
diltiazem will increase the level or effect of selumetinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration with strong or moderate CYP3A4 inhibitors cannot be avoided, reduce selumetinib dosage (refer to selumetinib monograph for further information). After discontinuation of the strong or moderate CYP3A4 inhibitor for 3 elimination half-lives, resume selumetinib dose that was taken before initiating the inhibitor.
- simvastatin
diltiazem will increase the level or effect of simvastatin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Benefits of combination therapy should be carefully weighed against the potential risks of combination. Limit simvastatin dose to no more than 10 mg/day and dilitazem dose to no more than 240 mg/day when used concurrently.
- siponimod
siponimod, diltiazem. Either increases effects of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Because of the potential additive effects on heart rate, siponimod should generally not be initiated in patients taking QT prolonging drugs with known arrhythmogenic properties, heart rate lowering calcium channel blockers, or other drugs that may decrease heart rate. If treatment considered, obtain cardiology consult regarding switching to non-heart-rate lowering drugs or appropriate monitoring for treatment initiation.
diltiazem will increase the level or effect of siponimod by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Coadministration of siponimod with a moderate or strong CYP3A4 inhibitor PLUS a moderate or strong CYP2C9 inhibitor is not recommended. - sonidegib
diltiazem will increase the level or effect of sonidegib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of sonidegib with moderate CYP3A4 inhibitors. If a moderate CYP3A inhibitor must be used, administer the moderate CYP3A inhibitor for <14 days and monitor closely for adverse reactions, particularly musculoskeletal adverse reactions.
- sotalol
diltiazem, sotalol. Either increases toxicity of the other by unspecified interaction mechanism. Avoid or Use Alternate Drug. Can increase risk of bradycardia.
- sotorasib
sotorasib will decrease the level or effect of diltiazem by P-glycoprotein (MDR1) efflux transporter. Avoid or Use Alternate Drug. If use is unavoidable, refer to the prescribing information of the P-gp substrate for dosage modifications.
- St John's Wort
St John's Wort will decrease the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.
- tazemetostat
diltiazem will increase the level or effect of tazemetostat by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of tazemetostat with moderate CYP3A4 inhibitors. If coadministration is unavoidable, reduce tazemetostat current dose (see drug monograph Dosage Modifications).
- tepotinib
tepotinib will increase the level or effect of diltiazem by P-glycoprotein (MDR1) efflux transporter. Avoid or Use Alternate Drug. If concomitant use unavoidable, reduce the P-gp substrate dosage if recommended in its approved product labeling.
- timolol
diltiazem, timolol. Either increases toxicity of the other by unspecified interaction mechanism. Avoid or Use Alternate Drug. Can increase risk of bradycardia.
- tolvaptan
diltiazem will increase the level or effect of tolvaptan by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. In patients taking concomitant moderate CYP3A inhibitors, reduce tolvaptan dose (see Prescribing Information). Consider further reductions if patients cannot tolerate the reduced dose. Interrupt tolvaptan temporarily for short term therapy with moderate CYP3A inhibitors if the recommended reduced doses are not available.
- tucatinib
tucatinib will increase the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid concomitant use of tucatinib with CYP3A substrates, where minimal concentration changes may lead to serious or life-threatening toxicities. If unavoidable, reduce CYP3A substrate dose according to product labeling.
- venetoclax
diltiazem will increase the level or effect of venetoclax by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If a moderate CYP3A inhibitor must be used, reduce the venetoclax dose by at least 50%. Monitor more closely for signs of venetoclax toxicities.
- vilazodone
diltiazem increases levels of vilazodone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If intolerable adverse effects occur when coadministered with moderate CYP3A4 inhibitors, reduce daily dose to 20 mg.
- voxelotor
voxelotor will increase the level or effect of diltiazem 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.
Monitor Closely (274)
- acalabrutinib
diltiazem will increase the level or effect of acalabrutinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Reduce acalabrutinib dose to 100 mg once daily if coadministered with a moderate CYP3A inhibitor.
- acebutolol
acebutolol and diltiazem both increase anti-hypertensive channel blocking. Modify Therapy/Monitor Closely.
- aldesleukin
aldesleukin increases effects of diltiazem by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.
- alfentanil
diltiazem will increase the level or effect of alfentanil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. In patients receiving both diltiazem and alfentanil, monitor for alfentanil toxicity (sedation, somnolence, confusion, impaired coordination, diminished reflexes, coma). Doses of alfentanil may need to be reduced.
- alfuzosin
diltiazem will increase the level or effect of alfuzosin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Increased exposure to alfuzosin may be expected when alfuzosin is concomitantly used with diltiazem. Monitor pulse and blood pressure.
- alprazolam
diltiazem will increase the level or effect of alprazolam by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Monitor for increased alprazolam side effects including drowsiness or fatigue, nausea, vomiting, diarrhea or constipation.
- amifostine
amifostine, diltiazem. Either increases effects of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration with blood pressure lowering agents may increase the risk and severity of hypotension associated with amifostine. When amifostine is used at chemotherapeutic doses, withhold blood pressure lowering medications for 24 hr prior to amifostine; if blood pressure lowering medication cannot be withheld, do not administer amifostine.
- amiodarone
diltiazem will increase the level or effect of amiodarone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Monitor increased effects and toxicities (eg, bradycardia, sinus arrest, decreased cardiac output) if amiodarone is concomitantly used with nondihydropyridine calcium channel blocker (ie, diltiazem).
- amitriptyline
diltiazem will increase the level or effect of amitriptyline by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Concomitant use with amitriptyline may alter blood pressure control.
- amlodipine
amlodipine and diltiazem both increase anti-hypertensive channel blocking. Use Caution/Monitor.
- amobarbital
amobarbital will decrease the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- apixaban
diltiazem increases levels of apixaban by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Patients with renal impairment receiving apixaban with drugs that are combined P-gp and weak or moderate CYP3A4 inhibitors may have significant increases in exposure compared with patients with normal renal function and no inhibitor use, since both pathways of apixaban elimination are affected. Since these increases may increase bleeding risk, use apixaban in this situation only if the potential benefit justifies the potential risk.
- aprepitant
aprepitant will increase the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- aripiprazole
diltiazem will increase the level or effect of aripiprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Closely monitor when aripiprazole is used with a moderate CYP3A4 inhibitor, due to potential risks for increased aripiprazole systemic exposure and effects. Refer to drug monograph for specific dosing modifications are dependent on indication, genotype, and drug formulation.
- armodafinil
diltiazem will increase the level or effect of armodafinil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
armodafinil will decrease the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. - artemether/lumefantrine
artemether/lumefantrine will decrease the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
diltiazem will increase the level or effect of artemether/lumefantrine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Coadministration with artemether/lumefantrine may increase artemether/lumefantrine levels and toxicities (eg, cardiac arrhythmias). - asenapine
asenapine and diltiazem both increase anti-hypertensive channel blocking. Use Caution/Monitor.
- atazanavir
atazanavir will increase the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Coadministration of atazanavir with diltiazem may increase diltiazem levels and toxicities (eg, hypotension, AV block). Consider reducing diltiazem dose by 50%. Monitor blood pressure and ECG.
- atenolol
atenolol and diltiazem both increase anti-hypertensive channel blocking. Modify Therapy/Monitor Closely.
- atogepant
diltiazem will increase the level or effect of atogepant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- atorvastatin
diltiazem will increase the level or effect of atorvastatin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. If concurrent therapy is required, monitor for signs and symptoms of myopathy or rhabdomyolysis (muscle pain, tenderness, or weakness, or discolored urine). If myopathy or rhabdomyolysis is diagnosed or suspected, monitor creatine kinase (CK) levels and discontinue use if CK levels show a marked increase.
- avanafil
diltiazem will increase the level or effect of avanafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Moderate CYP3A4 inhibitors may reduce avanafil clearance increasing systemic exposure to avanafil; increased levels may result in increased associated adverse events; maximum recommended dose of avanafil is 50 mg over 24 hours for patients taking concomitant moderate CYP3A4 inhibitors.
- axitinib
diltiazem increases levels of axitinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. If unable to avoid coadministration with moderate CYP3A4 inhibitors, monitor closely and reduce dose if necessary .
- bazedoxifene/conjugated estrogens
diltiazem will increase the level or effect of bazedoxifene/conjugated estrogens by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- belzutifan
belzutifan will decrease the level or effect of diltiazem 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.
- benzphetamine
benzphetamine will decrease the level or effect of diltiazem by pharmacodynamic antagonism. Use Caution/Monitor. Amphetamines may diminish antihypertensive effects of diltiazem. Monitor BP.
- berotralstat
berotralstat will increase the level or effect of diltiazem by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor. Monitor or titrate P-gp substrate dose if coadministered.
- betaxolol
betaxolol and diltiazem both increase anti-hypertensive channel blocking. Modify Therapy/Monitor Closely.
- bisoprolol
bisoprolol and diltiazem both increase anti-hypertensive channel blocking. Modify Therapy/Monitor Closely.
- bortezomib
diltiazem will increase the level or effect of bortezomib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Concomitant use with bortezomib may potentiate the risk of hypotension. Monitor BP.
- bosentan
diltiazem will decrease the level or effect of bosentan by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
bosentan will decrease the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. - bretylium
diltiazem, bretylium. Either increases effects of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Each drug may cause hypotension.
- brexpiprazole
diltiazem will increase the level or effect of brexpiprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Administer a quarter of brexpiprazole dose if coadministered with a moderate CYP3A4 inhibitor PLUS a strong/moderate CYP2D6 inhibitor.
- buprenorphine subdermal implant
diltiazem will increase the level or effect of buprenorphine subdermal implant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Monitor patients already on buprenorphine subdermal implant who require newly-initiated treatment with CYP3A4 inhibitors for signs and symptoms of overmedication. If the dose of the concomitant CYP3A4 inhibitor cannot be reduced or discontinued, implant removal may be necessary and the patient should then be treated with a buprenorphine dosage form that permits dose adjustments. If a CYP3A4 inhibitor is discontinued in a patient who has been stabilized on buprenorphine, monitor the patient for withdrawal.
- buprenorphine, long-acting injection
diltiazem will increase the level or effect of buprenorphine, long-acting injection by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Patients who transfer to buprenorphine long-acting injection from transmucosal buprenorphine coadministered with CYP3A4 inhibitors should be monitored to ensure buprenorphine plasma levels are adequate. Within 2 weeks, if signs and symptoms of buprenorphine toxicity or overdose occur and the concomitant CYP3A4 inhibitor cannot be reduced or discontinued, transition the patient back to a buprenorphine formulation that permits dose adjustments.
- buspirone
diltiazem will increase the level or effect of buspirone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Coadministration of buspirone with diltiazem may increase plasma concentrations and/or toxicities of buspirone. Dose adjustments may be necessary.
- butabarbital
butabarbital will decrease the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- butalbital
butalbital will decrease the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- cabazitaxel
diltiazem will increase the level or effect of cabazitaxel by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- cabozantinib
diltiazem will increase the level or effect of cabozantinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- calcium acetate
calcium acetate decreases effects of diltiazem by pharmacodynamic antagonism. Use Caution/Monitor.
- calcium carbonate
calcium carbonate decreases effects of diltiazem by pharmacodynamic antagonism. Use Caution/Monitor.
- calcium chloride
calcium chloride decreases effects of diltiazem by pharmacodynamic antagonism. Use Caution/Monitor.
- calcium citrate
calcium citrate decreases effects of diltiazem by pharmacodynamic antagonism. Use Caution/Monitor.
- calcium gluconate
calcium gluconate decreases effects of diltiazem by pharmacodynamic antagonism. Use Caution/Monitor.
- cannabidiol
diltiazem will increase the level or effect of cannabidiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Monitor increased cannabidol effects and toxicities if coadministered with moderate CYP3A4 inhibitors. Reduce cannabidiol dose if necessary.
- carbamazepine
carbamazepine will decrease the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely.
- carvedilol
carvedilol and diltiazem both increase anti-hypertensive channel blocking. Modify Therapy/Monitor Closely.
- celiprolol
celiprolol and diltiazem both increase anti-hypertensive channel blocking. Modify Therapy/Monitor Closely.
- cenobamate
cenobamate will decrease the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Increase dose of CYP3A4 substrate, as needed, when coadministered with cenobamate.
- cilostazol
diltiazem will increase the level or effect of cilostazol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Consider reducing cilostazol dose to 50 mg PO BID when administered with diltiazem.
- cimetidine
cimetidine will increase the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Consider alternatives to cimetidine in patients receiving diltiazem. If no alternative is available, monitor for the effects of diltiazem following cimetidine initiation/discontinuation.
cimetidine will increase the level or effect of diltiazem by basic (cationic) drug competition for renal tubular clearance. Modify Therapy/Monitor Closely. Exercise caution when concomitantly using diltiazem with atazanavir. Consider reducing the diltiazem dose by 50%. ECG monitoring is recommended. - cinacalcet
diltiazem will increase the level or effect of cinacalcet by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- clarithromycin
clarithromycin will increase the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Increased effect of calcium channel blockers may lead to hypotension, edema, decreased HR, and acute kidney injury due to reduced renal blood flow
- clevidipine
clevidipine and diltiazem both increase anti-hypertensive channel blocking. Use Caution/Monitor.
- clopidogrel
diltiazem will decrease the level or effect of clopidogrel by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Coadministration of clopidogrel and a calcium channel blocking agent may decrease the effect of clopidogrel on platelet inhibition, possibly increasing the risk of atherothrombotic events. Clopidogrel requires hepatic biotransformation to an active metabolite, mediated by the 3A4 enzyme. Diltiazem is a 3A4 inhibitor and may decrease the hepatic metabolism of clopidogrel to its active metabolite.
- clozapine
diltiazem will increase the level or effect of clozapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Concomitant treatment with clozapine and CYP2D6 or CYP3A4 inhibitors can increase clozapine levels and lead to adverse reactions. Use caution and monitor patients closely when using such inhibitors. Consider reducing clozapine dose.
- cobicistat
cobicistat will increase the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- conivaptan
conivaptan will increase the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- conjugated estrogens
diltiazem will increase the level or effect of conjugated estrogens by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- conjugated estrogens, vaginal
diltiazem will increase the level or effect of conjugated estrogens, vaginal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- cortisone
diltiazem will increase the level or effect of cortisone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- crizotinib
crizotinib increases levels of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Dose reduction may be needed for coadministered drugs that are predominantly metabolized by CYP3A.
diltiazem increases levels of crizotinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Caution should be exercised with concomitant use of moderate CYP3A inhibitors. . - cyclosporine
diltiazem will increase the level or effect of cyclosporine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Monitor serum cyclosporine concentrations if diltiazem or verapamil are initiated/ discontinued. During coadministration of cyclosporine and diltiazem, monitor for decreases in blood pressure.
- dabrafenib
dabrafenib will decrease the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely.
- daridorexant
diltiazem will increase the level or effect of daridorexant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Daridorexant dose should not exceed 25 mg per night when coadministered with moderate CYP3A4 inhibitors.
- darifenacin
diltiazem will increase the level or effect of darifenacin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- darunavir
darunavir will increase the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
diltiazem will increase the level or effect of darunavir by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Consider avoiding the concomitant use of protease inhibitors and nondihydropyridine calcium channel blockers (CCB). Monitor for toxicities of the CCB if a protease inhibitor is initiated/dose increased. - dasatinib
diltiazem will increase the level or effect of dasatinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- deferasirox
deferasirox will decrease the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- deflazacort
diltiazem will increase the level or effect of deflazacort by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Decrease deflazacort dose to one-third of the recommended dose if coadministered with moderate or strong CYP3A4 inhibitors.
- dexamethasone
diltiazem will increase the level or effect of dexamethasone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- diazepam
diltiazem will increase the level or effect of diazepam by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- diazepam intranasal
diltiazem will increase the level or effect of diazepam intranasal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Strong or moderate CYP3A4 inhibitors may decrease rate of diazepam elimination, thereby increasing adverse reactions to diazepam.
- disopyramide
diltiazem will increase the level or effect of disopyramide by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- docetaxel
diltiazem will increase the level or effect of docetaxel by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- donepezil
diltiazem will increase the level or effect of donepezil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- doxazosin
doxazosin and diltiazem both increase anti-hypertensive channel blocking. Use Caution/Monitor.
- doxorubicin
diltiazem will increase the level or effect of doxorubicin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- doxorubicin liposomal
diltiazem will increase the level or effect of doxorubicin liposomal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- dronedarone
dronedarone will increase the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Calcium channel blockers with depressant effects on sinus and AV nodes could potentiate dronedarone's effects on conduction. Initiate calcium channel blockers at a lower dose and titrate up only after ECG verification of tolerability.
- duvelisib
duvelisib will increase the level or effect of diltiazem 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 diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- elagolix
elagolix will decrease the level or effect of diltiazem 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.
- elvitegravir/cobicistat/emtricitabine/tenofovir DF
elvitegravir/cobicistat/emtricitabine/tenofovir DF increases levels of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Exercise caution and monitor upon coadministration of calcium channel blockers with elvitegravir/cobicistat/emtricitabine/tenofovir DF.
- encorafenib
encorafenib, diltiazem. 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.
- ergotamine
diltiazem will increase the level or effect of ergotamine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- erlotinib
diltiazem will increase the level or effect of erlotinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- eslicarbazepine acetate
eslicarbazepine acetate will decrease the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- esmolol
esmolol and diltiazem both increase anti-hypertensive channel blocking. Modify Therapy/Monitor Closely.
- estradiol
diltiazem will increase the level or effect of estradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- estrogens conjugated synthetic
diltiazem will increase the level or effect of estrogens conjugated synthetic by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- estrogens esterified
diltiazem will increase the level or effect of estrogens esterified by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- estropipate
diltiazem will increase the level or effect of estropipate by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- etrasimod
etrasimod, diltiazem. pharmacodynamic synergism. Use Caution/Monitor. Transient decrease in heart rate and AV conduction delays may occur when initiating etrasimod. Concomitant use of etrasimod in patients receiving stable beta-blocker treatment did not result in additive effects on heart rate reduction. However, risk of additive heart rate reduction following initiation of beta-blocker therapy with stable etrasimod treatment or concomitant use with other drugs that may decrease heart rate is unknown. .
- etravirine
diltiazem will increase the level or effect of etravirine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
etravirine will decrease the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. - everolimus
diltiazem will increase the level or effect of everolimus by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Dose adjustment is based on indication. In breast cancer, PNET, renal cell cancer, or renal angiomyolipoma w/ TSC patents, decrease everolimus dose to 2.5-5 mg/day; decrease everolimus dose 50% and monitor levels in SEGA patients.
- fedratinib
fedratinib will increase the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Adjust dose of drugs that are CYP3A4 substrates as necessary.
- felodipine
diltiazem will increase the level or effect of felodipine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
diltiazem and felodipine both increase anti-hypertensive channel blocking. Use Caution/Monitor. - fentanyl
diltiazem will increase the level or effect of fentanyl 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.
- fentanyl intranasal
diltiazem will increase the level or effect of fentanyl intranasal 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.
- fentanyl transdermal
diltiazem will increase the level or effect of fentanyl transdermal 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.
- fentanyl transmucosal
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.
- fesoterodine
diltiazem will increase the level or effect of fesoterodine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- finerenone
diltiazem 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 moderate CYP3A4 inhibitors. Adjust finererone dosage as needed.
- fingolimod
diltiazem increases effects of fingolimod by pharmacodynamic synergism. Use Caution/Monitor. Both medications decrease heart rate. Monitor patients on concomitant therapy, particularly in the first 6 hours after fingolimod is initiated or after a treatment interruption of at least two weeks, for bradycardia and atrioventricular block. To identify underlying risk factors of bradycardia and AV block, obtain a new or recent ECG in patients using calcium channel blockers prior to starting fingolimod.
- fluconazole
fluconazole will increase the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- fludrocortisone
diltiazem will increase the level or effect of fludrocortisone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- fluvoxamine
fluvoxamine will increase the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- fosamprenavir
diltiazem will increase the level or effect of fosamprenavir by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Protease Inhibitors may decrease metabolism of diltiazem. Increased serum concentrations of diltiazem may increase risk of AV nodal blockade.
fosamprenavir will increase the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. - fosaprepitant
fosaprepitant will increase the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- fosphenytoin
fosphenytoin will decrease the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
diltiazem will increase the level or effect of fosphenytoin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Monitor for phenytoin toxicity if diltiazem is initiated/dose increased, or decreased phenytoin effects if diltiazem is discontinued/dose decreased. Monitor for reduced diltiazem therapeutic effects with concomitant fosphenytoin. - fostamatinib
fostamatinib will increase the level or effect of diltiazem by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor. Concomitant use of fostamatinib may increase concentrations of P-gp substrates. Monitor for toxicities of the P-gp substrate drug that may require dosage reduction when given concurrently with fostamatinib.
- gepirone
diltiazem will increase the level or effect of gepirone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Reduce gepirone dose by 50% when used concomitantly with a moderate CYP3A4 inhibitor.
- glecaprevir/pibrentasvir
glecaprevir/pibrentasvir will increase the level or effect of diltiazem by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor.
- grapefruit
grapefruit will increase the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- griseofulvin
griseofulvin will decrease the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- guanfacine
diltiazem will increase the level or effect of guanfacine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Reduce guanfacine ER dose by 50% when initiating concomitant therapy with a moderate CYP3A4 inhibitor. When discontinuing moderate CYP3A4 inhibitor, increase guanfacine dose to recommended dose range. Monitor for excessive guanfacine response (eg, hypotension, bradycardia, CNS depression).
- hawthorn
hawthorn increases effects of diltiazem by pharmacodynamic synergism. Use Caution/Monitor.
- hydrocortisone
diltiazem will increase the level or effect of hydrocortisone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- ifosfamide
diltiazem will decrease the level or effect of ifosfamide by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Use of a CYP3A4 inhibitor may decrease metabolism of ifosfamide, potentially reducing ifosfamide therapeutic effects.
- iloperidone
iloperidone increases levels of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Iloperidone is a time-dependent CYP3A inhibitor and may lead to increased plasma levels of drugs predominantly eliminated by CYP3A4. Coadministration with iloperidone may increase the risk for QT prolongation and patients should be carefully monitor.
- imatinib
diltiazem will increase the level or effect of imatinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- imipramine
diltiazem will increase the level or effect of imipramine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- indinavir
diltiazem will increase the level or effect of indinavir by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- irinotecan
diltiazem will increase the level or effect of irinotecan by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- irinotecan liposomal
diltiazem will increase the level or effect of irinotecan liposomal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- isavuconazonium sulfate
diltiazem will increase the level or effect of isavuconazonium sulfate by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- isradipine
diltiazem will increase the level or effect of isradipine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
diltiazem and isradipine both increase anti-hypertensive channel blocking. Use Caution/Monitor. - istradefylline
istradefylline will increase the level or effect of diltiazem 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.
istradefylline will increase the level or effect of diltiazem by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor. Istradefylline 40 mg/day increased peak levels and AUC of P-gp substrates in clinical trials. Consider dose reduction of sensitive P-gp substrates. - itraconazole
diltiazem will increase the level or effect of itraconazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Coadministration of diltiazem and itraconazole may increase both drug levels, toxities, and additive negative inotropic effects.
itraconazole will increase the level or effect of diltiazem by Other (see comment). Modify Therapy/Monitor Closely. CCBs elicit negative inotropic effects which may be additive to those of itraconazole; additionally, itraconazole can inhibit the metabolism of calcium channel blockers. Monitor for adverse reactions. Concomitant drug dose reduction may be necessary. - ivacaftor
diltiazem will increase the level or effect of ivacaftor by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Reduce ivacaftor dose if coadministered with moderate CYP3A4 inhibitors. See specific ivacaftor-containing product for precise dosage modification.
- ixabepilone
diltiazem will increase the level or effect of ixabepilone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- ketoconazole
diltiazem will increase the level or effect of ketoconazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Coadministration of diltiazem and ketoconazole may increase both drug levels, toxities, and additive negative inotropic effects.
ketoconazole will increase the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. - labetalol
labetalol and diltiazem both increase anti-hypertensive channel blocking. Modify Therapy/Monitor Closely.
- lapatinib
diltiazem will increase the level or effect of lapatinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- larotrectinib
diltiazem will increase the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- lasmiditan
diltiazem increases effects of lasmiditan by pharmacodynamic synergism. Use Caution/Monitor. Lasmiditan has been associated with a lowering of heart rate (HR). In a drug interaction study, addition of a single 200-mg dose of lasmiditan to propranolol decreased HR by an additional 5 bpm compared to propranolol alone, for a mean maximum of 19 bpm.
- lefamulin
diltiazem will increase the level or effect of lefamulin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Monitor for adverse effects if lefamulin is coadministered with moderate CYP3A inhibitors.
- lenacapavir
lenacapavir will increase the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Lencapavir (a moderate CYP3A4 inhibitor) may increase CYP3A4 substrates initiated within 9 months after last SC dose of lenacapavir, which may increase potential risk of adverse reactions of CYP3A4 substrates.
- letermovir
diltiazem will increase the level or effect of letermovir by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- levamlodipine
diltiazem will increase the level or effect of levamlodipine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Coadministration with moderate and strong CYP3A inhibitors results in increased systemic exposure to amlodipine and may require dose reduction. Monitor for symptoms of hypotension and edema when amlodipine is coadministered with CYP3A inhibitors to determine the need for dose adjustment.
- levodopa
levodopa increases effects of diltiazem by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.
- levoketoconazole
levoketoconazole will increase the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely.
diltiazem will increase the level or effect of levoketoconazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Coadministration of diltiazem and ketoconazole may increase both drug levels, toxities, and additive negative inotropic effects. - lithium
diltiazem increases toxicity of lithium by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of neurotoxicity.
- lopinavir
diltiazem will increase the level or effect of lopinavir by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- lumateperone
diltiazem will increase the level or effect of lumateperone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Reduce lumateperone dose to 21 mg/day if coadministered with moderate CYP3A4 inhibitors.
- lumefantrine
diltiazem will increase the level or effect of lumefantrine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
lumefantrine will decrease the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. - lurasidone
diltiazem increases levels of lurasidone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Decrease starting dose of lurasidone to 20 mg/day and maximum daily dose of lurasidone 80 mg when coadministered with moderate CYP3A4 inhibitors. Concurrent use may increase risk of lurasidone-related adverse reactions.
- magnesium supplement
magnesium supplement, diltiazem. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Calcium channel blockers may increase toxic effects of magnesium; magnesium may increase hypotensive effects of calcium channel blockers.
- maraviroc
diltiazem will increase the level or effect of maraviroc by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- marijuana
diltiazem will increase the level or effect of marijuana by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- mavacamten
diltiazem will increase the level or effect of mavacamten by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Inititiation of moderate CYP3A4 inhibitors may require decreased mavacamten dose.
- mefloquine
mefloquine increases levels of diltiazem by decreasing metabolism. Use Caution/Monitor. Risk of arrhythmia.
diltiazem will increase the level or effect of mefloquine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. - metformin
diltiazem decreases effects of metformin by pharmacodynamic antagonism. Use Caution/Monitor. Patient should be closely observed for loss of blood glucose control; when drugs are withdrawn from a patient receiving metformin, patient should be observed closely for hypoglycemia.
- methadone
diltiazem will increase the level or effect of methadone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- methamphetamine
methamphetamine will decrease the level or effect of diltiazem by pharmacodynamic antagonism. Use Caution/Monitor. Amphetamines may diminish antihypertensive effects of diltiazem. Monitor BP.
- methylphenidate
methylphenidate will decrease the level or effect of diltiazem by pharmacodynamic antagonism. Use Caution/Monitor. Methylphenidate may diminish antihypertensive effects. Monitor BP.
- methylprednisolone
diltiazem will increase the level or effect of methylprednisolone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- metoprolol
metoprolol and diltiazem both increase anti-hypertensive channel blocking. Modify Therapy/Monitor Closely.
- midazolam
diltiazem will increase the level or effect of midazolam by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Midazolam dose adjustments may be necessary in patients receiving concomitant diltiazem and midazolam. Monitor for signs of midazolam toxicity (eg, sedation, somnolence, confusion, impaired coordination, diminished reflexes, coma).
- mifepristone
diltiazem will increase the level or effect of mifepristone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Coadministration of mifepristone, CYP3A4 inhibitor with diltiazem, CYP3A4 substrate may increase plasma concentrations of diltiazem. Discontinuation or dose reduction of diltiazem may be necessary with mifepristone coadministration.
mifepristone will increase the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. - mitotane
mitotane decreases levels of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Mitotane is a strong inducer of cytochrome P-4503A4; monitor when coadministered with CYP3A4 substrates for possible dosage adjustments.
- moxisylyte
moxisylyte and diltiazem both increase anti-hypertensive channel blocking. Use Caution/Monitor.
- nadolol
nadolol and diltiazem both increase anti-hypertensive channel blocking. Modify Therapy/Monitor Closely.
- nafcillin
nafcillin will decrease the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- naldemedine
diltiazem increases levels of naldemedine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Monitor naldemedine for potential adverse effects if coadministered with strong or moderate CYP3A4 inhibitors.
- nebivolol
nebivolol and diltiazem both increase anti-hypertensive channel blocking. Modify Therapy/Monitor Closely.
- nefazodone
nefazodone will increase the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely.
- nelfinavir
diltiazem will increase the level or effect of nelfinavir by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Monitor potential serious and/or life threatening reactions such as cardiac arrhythmias.
nelfinavir will increase the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. - nevirapine
nevirapine will decrease the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- nicardipine
diltiazem will increase the level or effect of nicardipine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Nondihydropyridine calcium channel blockers (CCB) may increase the serum concentration of dihydropyridine CCB. Monitor for toxicities of dihydropyridine CCB if diltiazem are initiated/dose increased, or decreased effects if diltiazem are discontinued/dose decreased.
diltiazem and nicardipine both increase anti-hypertensive channel blocking. Use Caution/Monitor. - nifedipine
diltiazem will increase the level or effect of nifedipine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Exercise caution when coadministering diltiazem and nifedipine and consider reducing nifedipine dose.
nifedipine will increase the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
diltiazem and nifedipine both increase anti-hypertensive channel blocking. Use Caution/Monitor. - nilotinib
diltiazem will increase the level or effect of nilotinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
nilotinib will increase the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. - nimodipine
diltiazem will increase the level or effect of nimodipine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- nirmatrelvir
nirmatrelvir will increase the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. May consider temporary diltiazem dose reduction.
- nirmatrelvir/ritonavir
nirmatrelvir/ritonavir will increase the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Consider reducing diltiazem dose by 50% during coadministration and for 3 more days after the last nirmatrelvir/ritonavir dose.
- nisoldipine
diltiazem will increase the level or effect of nisoldipine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
diltiazem and nisoldipine both increase anti-hypertensive channel blocking. Use Caution/Monitor. - nitroglycerin rectal
nitroglycerin rectal, diltiazem. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Marked orthostatic hypotension has been reported when calcium channel blockers and organic nitrates were used concomitantly. Observe for possible additive hypotensive effects during concomitant use. .
- nitroprusside sodium
diltiazem increases effects of nitroprusside sodium by pharmacodynamic synergism. Use Caution/Monitor.
- norgestrel
diltiazem will increase the level or effect of norgestrel by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Strong or moderate CYP3A4 inhibitors may increase systemic concentration of norgestrel, which may increase risk for adverse effects
- oliceridine
diltiazem will increase the level or effect of oliceridine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. If concomitant use is necessary, may require less frequent oliceridine dosing. Closely monitor for respiratory depression and sedation and titrate subsequent doses accordingly. If inhibitor is discontinued, consider increase oliceridine dosage until stable drug effects are achieved. Monitor for signs of opioid withdrawal.
- ombitasvir/paritaprevir/ritonavir & dasabuvir (DSC)
ombitasvir/paritaprevir/ritonavir & dasabuvir (DSC) will increase the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely.
- oxcarbazepine
oxcarbazepine will decrease the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- oxybutynin
diltiazem will increase the level or effect of oxybutynin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- oxycodone
diltiazem will increase the level or effect of oxycodone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- paclitaxel
diltiazem will increase the level or effect of paclitaxel by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Monitor for dose-related toxicities (eg, diarrhea, mucositis, myelosuppression, peripheral neuropathy) of paclitaxel during coadministration.
- paclitaxel protein bound
diltiazem will increase the level or effect of paclitaxel protein bound by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Monitor for dose-related toxicities (eg, diarrhea, mucositis, myelosuppression, peripheral neuropathy) of paclitaxel during coadministration.
- palbociclib
diltiazem will increase the level or effect of palbociclib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- palovarotene
diltiazem will increase the level or effect of palovarotene by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Avoid coadministration of palovarotene, a CYP3A substrate, with moderate CYP3A inhibitors. If unavoidable, reduce palovarotene dose by 50%.
- pazopanib
diltiazem will increase the level or effect of pazopanib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- penbutolol
penbutolol and diltiazem both increase anti-hypertensive channel blocking. Modify Therapy/Monitor Closely.
- pentobarbital
pentobarbital will decrease the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- phendimetrazine
phendimetrazine will decrease the level or effect of diltiazem by pharmacodynamic antagonism. Use Caution/Monitor. Amphetamines may diminish antihypertensive effects of diltiazem. Monitor BP.
- phenobarbital
phenobarbital will decrease the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- phenoxybenzamine
phenoxybenzamine and diltiazem both increase anti-hypertensive channel blocking. Use Caution/Monitor.
- phentermine
phentermine will decrease the level or effect of diltiazem by pharmacodynamic antagonism. Use Caution/Monitor. Amphetamines may diminish antihypertensive effects of diltiazem. Monitor BP.
- phentolamine
phentolamine and diltiazem both increase anti-hypertensive channel blocking. Use Caution/Monitor.
- phenytoin
phenytoin will decrease the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- pindolol
pindolol and diltiazem both increase anti-hypertensive channel blocking. Modify Therapy/Monitor Closely.
- pioglitazone
diltiazem will increase the level or effect of pioglitazone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- posaconazole
posaconazole will increase the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- prazosin
prazosin and diltiazem both increase anti-hypertensive channel blocking. Use Caution/Monitor.
- prednisolone
diltiazem will increase the level or effect of prednisolone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Closely monitor for evidence of excessive response to corticosteroid therapy if used with diltiazem. Consider dosage adjustment if necessary.
- prednisone
diltiazem will increase the level or effect of prednisone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Closely monitor for evidence of excessive response to corticosteroid therapy if used with diltiazem. Consider dosage adjustment if necessary.
- propranolol
propranolol and diltiazem both increase anti-hypertensive channel blocking. Modify Therapy/Monitor Closely.
- quetiapine
diltiazem will increase the level or effect of quetiapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- quinidine
diltiazem will increase the level or effect of quinidine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
quinidine will increase the level or effect of diltiazem by basic (cationic) drug competition for renal tubular clearance. Use Caution/Monitor. - quinine
diltiazem will increase the level or effect of quinine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- quinupristin/dalfopristin
quinupristin/dalfopristin will increase the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- ranolazine
diltiazem will increase the level or effect of ranolazine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Limit the dose of ranolazine to a maximum of 500 mg twice a day when used concomitantly with diltiazem.
- repaglinide
diltiazem will increase the level or effect of repaglinide by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Monitor glucose and hypoglycemic symptoms (eg, headache, dizziness, drowsiness, nervousness, confusion, tremor, hunger, weakness, perspiration, palpitations).
- ribociclib
ribociclib will increase the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- rifabutin
rifabutin will decrease the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Coadministration with diltiazem and rifamycin derivatives may decrease diltiazem levels. Consider dosage adjustment and close monitoring of pharmacologic effects (eg, blood pressure) whenever a rifamycin derivative is added to or discontinued from therapy.
- rifapentine
rifapentine will decrease the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Coadministration with diltiazem and rifamycin derivatives may decrease diltiazem levels. Consider dosage adjustment and close monitoring of pharmacologic effects (eg, blood pressure) whenever a rifamycin derivative is added to or discontinued from therapy.
- rimegepant
diltiazem will increase the level or effect of rimegepant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Avoid repeating rimegepant dose within 48 hr if coadministered with a moderate CYP3A4 inhibitor.
- riociguat
riociguat, diltiazem. Either increases effects of the other by anti-hypertensive channel blocking. Use Caution/Monitor. Monitor patients closely for additive hypotensive effects if two or more of these agents are combined.
- ritonavir
diltiazem will increase the level or effect of ritonavir by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
ritonavir will increase the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. - rivaroxaban
diltiazem increases levels of rivaroxaban by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Patients with renal impairment receiving rivaroxaban with drugs that are combined P-gp and weak or moderate CYP3A4 inhibitors may have significant increases in exposure compared with patients with normal renal function and no inhibitor use, since both pathways of rivaroxaban elimination are affected. Since these increases may increase bleeding risk, use rivaroxaban in this situation only if the potential benefit justifies the potential risk.
- rucaparib
rucaparib will increase the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Adjust dosage of CYP3A4 substrates, if clinically indicated.
- rufinamide
rufinamide will decrease the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- ruxolitinib
diltiazem will increase the level or effect of ruxolitinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- ruxolitinib topical
diltiazem will increase the level or effect of ruxolitinib topical by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- saquinavir
diltiazem will increase the level or effect of saquinavir by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
saquinavir will increase the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. - sarecycline
sarecycline will increase the level or effect of diltiazem by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor. Monitor for toxicities of P-gp substrates that may require dosage reduction when coadministered with P-gp inhibitors.
- saxagliptin
diltiazem will increase the level or effect of saxagliptin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Closely monitor glucose when saxagliptin is concomitantly used with moderate CYP3A4 inhibitors.
- secobarbital
secobarbital will decrease the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- shepherd's purse
shepherd's purse, diltiazem. Other (see comment). Use Caution/Monitor. Comment: Theoretically, shepherd's purse may interfere with BP control.
- sildenafil
diltiazem will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- silodosin
diltiazem will increase the level or effect of silodosin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
silodosin and diltiazem both increase anti-hypertensive channel blocking. Use Caution/Monitor. - sirolimus
diltiazem will increase the level or effect of sirolimus by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- sodium sulfate/?magnesium sulfate/potassium chloride
diltiazem, sodium sulfate/?magnesium sulfate/potassium chloride. Either decreases toxicity of the other by unknown mechanism. Use Caution/Monitor. Monitor for hypotension or muscle weakness in patients receiving calcium channel blockers with elevated serum magnesium concentrations.
- sodium sulfate/potassium sulfate/magnesium sulfate
diltiazem, sodium sulfate/potassium sulfate/magnesium sulfate. Either decreases toxicity of the other by unknown mechanism. Use Caution/Monitor. Monitor for hypotension or muscle weakness in patients receiving calcium channel blockers with elevated serum magnesium concentrations.
- solifenacin
diltiazem will increase the level or effect of solifenacin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- sotalol
sotalol and diltiazem both increase anti-hypertensive channel blocking. Modify Therapy/Monitor Closely.
- sparsentan
diltiazem will increase the level or effect of sparsentan by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. No dosage adjustment needed. Monitor blood pressure, serum potassium, edema, and kidney function regularly if sparsentan is coadministered with moderate CYP3A4 inhibitors.
- stiripentol
stiripentol, diltiazem. 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.
- sufentanil
diltiazem will increase the level or effect of sufentanil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. The incidence and degree of bradycardia and hypotension during induction with sufentanil citrate may be greater in patients on chronic calcium channel and beta blocker therapy.
- sufentanil SL
diltiazem will increase the level or effect of sufentanil SL by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Coadministration of sufentanil SL with any CYP3A4 inhibitor may increase sufentanil plasma concentration, and, thereby increase or prolonged adverse effects, including potentially fatal respiratory depression.
- sunitinib
diltiazem will increase the level or effect of sunitinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- suvorexant
diltiazem will increase the level or effect of suvorexant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Decrease suvorexant starting dose to 5 mg HS if coadministered with moderate CYP3A4 inhibitors
- tacrolimus
diltiazem will increase the level or effect of tacrolimus by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- tadalafil
diltiazem will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Risk of hypotension.
- tamoxifen
diltiazem, tamoxifen. affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. CYP3A4 inhibition decreases metabolism of tamoxifen to N-desmethyl tamoxifen (active metabolite with similar biologic activity).
- tamsulosin
diltiazem increases levels of tamsulosin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Dose reduction may be needed for coadministered drugs that are predominantly metabolized by CYP3A.
- tazemetostat
tazemetostat will decrease the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- tecovirimat
tecovirimat will decrease the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Tecovirimat is a weak CYP3A4 inducer. Monitor sensitive CYP3A4 substrates for effectiveness if coadministered.
- temsirolimus
diltiazem will increase the level or effect of temsirolimus by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
diltiazem increases toxicity of temsirolimus by Other (see comment). Use Caution/Monitor. Comment: Combination of mTOR inhibitors with calcium channel blockers increases risk of angioedema. - terazosin
terazosin and diltiazem both increase anti-hypertensive channel blocking. Use Caution/Monitor.
- tezacaftor
diltiazem will increase the level or effect of tezacaftor by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. When tezacaftor/ivacaftor is combined with moderate CYP3A4 inhibitors, administer tezacaftor/ivacaftor (100 mg/150 mg) in the morning, every other day. Administer ivacaftor 150 mg alonein the evening, every other day, on alternate days from tezacaftor/ivacaftor.
- theophylline
diltiazem will increase the level or effect of theophylline by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- timolol
timolol and diltiazem both increase anti-hypertensive channel blocking. Modify Therapy/Monitor Closely.
- tipranavir
diltiazem will increase the level or effect of tipranavir by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
tipranavir will increase the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. - tofacitinib
diltiazem increases levels of tofacitinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. No specific dose adjustment recommended when tofacitinib coadministered with moderate CYP3A4 inhibitors; decrease tofacitinib dose if coadministered with both moderate CYP3A4 and potent CYP2C19 inhibitors.
- tolterodine
diltiazem will increase the level or effect of tolterodine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- topiramate
topiramate will decrease the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- trabectedin
diltiazem will increase the level or effect of trabectedin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- trazodone
diltiazem will increase the level or effect of trazodone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- triamcinolone acetonide injectable suspension
diltiazem will increase the level or effect of triamcinolone acetonide injectable suspension by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- triazolam
diltiazem will increase the level or effect of triazolam by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- trimagnesium citrate anhydrous
trimagnesium citrate anhydrous, diltiazem. Either increases effects of the other by Other (see comment). Use Caution/Monitor. Comment: Possible additive effect of magnesium and calcium channel blockers on reduction of ionic calcium may increase risk of hypotension or muscle weakness.
- trimipramine
diltiazem will increase the level or effect of trimipramine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- tucatinib
tucatinib will increase the level or effect of diltiazem by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor. Consider reducing the dosage of P-gp substrates, where minimal concentration changes may lead to serious or life-threatening toxicities.
- vardenafil
diltiazem will increase the level or effect of vardenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Vardenafil dose may need to be reduced if coadministered with moderate or strong CYP3A4 inhibitors
- vemurafenib
vemurafenib increases levels of diltiazem by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor.
- verapamil
diltiazem will increase the level or effect of verapamil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
verapamil will increase the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. These agents have additive hypotensive effects that may be beneficial however, it is important to monitor patients carefully.
diltiazem and verapamil both increase anti-hypertensive channel blocking. Use Caution/Monitor. Antihypertensives may enhance the hypotensive effects of other antihypertensive agents when used together. - vinblastine
diltiazem will increase the level or effect of vinblastine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- vincristine
diltiazem will increase the level or effect of vincristine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- vincristine liposomal
diltiazem will increase the level or effect of vincristine liposomal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- vinorelbine
diltiazem will increase the level or effect of vinorelbine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- voclosporin
diltiazem will increase the level or effect of voclosporin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Reduce voclosporin daily dosage to 15.8 mg PO in AM and 7.9 mg PO in PM.
- voriconazole
voriconazole will increase the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Combo may increase risk of hypotension, bradycardia, AV block.
voriconazole increases levels of diltiazem by decreasing metabolism. Use Caution/Monitor. - xipamide
xipamide increases effects of diltiazem by pharmacodynamic synergism. Use Caution/Monitor.
- zanubrutinib
diltiazem will increase the level or effect of zanubrutinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Reduce zanubrutinib (a CYP3A4 substrate) to 80 mg PO BID to when coadministered with a moderate CYP3A4 inhibitor. Interrupt dose as recommended for adverse reactions. After discontinuing the CYP3A4 inhibitor, resume previous dose of zanubrutinib.
Minor (34)
- acetazolamide
acetazolamide will increase the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.
- agrimony
agrimony increases effects of diltiazem by pharmacodynamic synergism. Minor/Significance Unknown.
- anastrozole
anastrozole will increase the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.
- aspirin
diltiazem increases effects of aspirin by unknown mechanism. Minor/Significance Unknown. Enhanced antiplatelet activity.
- aspirin rectal
diltiazem increases effects of aspirin rectal by unknown mechanism. Minor/Significance Unknown. Enhanced antiplatelet activity.
- aspirin/citric acid/sodium bicarbonate
diltiazem increases effects of aspirin/citric acid/sodium bicarbonate by unknown mechanism. Minor/Significance Unknown. Enhanced antiplatelet activity.
- atracurium
diltiazem increases effects of atracurium by pharmacodynamic synergism. Minor/Significance Unknown. Ca Channel Blockers interfere w/Ach release from prejunctional axon.
- brimonidine
brimonidine increases effects of diltiazem by pharmacodynamic synergism. Minor/Significance Unknown.
- capivasertib
diltiazem will increase the level or effect of capivasertib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown. Reduce capivasertib dose if coadministered with moderate CYP3A inhibitors.
- choline magnesium trisalicylate
diltiazem increases effects of choline magnesium trisalicylate by unknown mechanism. Minor/Significance Unknown. Enhanced antiplatelet activity.
- cisatracurium
diltiazem increases effects of cisatracurium by pharmacodynamic synergism. Minor/Significance Unknown. Ca Channel Blockers interfere w/Ach release from prejunctional axon.
- cyclophosphamide
cyclophosphamide will increase the level or effect of diltiazem by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.
- dutasteride
diltiazem will increase the level or effect of dutasteride by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.
- estradiol vaginal
diltiazem will increase the level or effect of estradiol vaginal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.
- fo-ti
fo-ti increases effects of diltiazem by pharmacodynamic synergism. Minor/Significance Unknown.
- forskolin
forskolin increases effects of diltiazem by pharmacodynamic synergism. Minor/Significance Unknown.
- galantamine
diltiazem will increase the level or effect of galantamine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.
- lily of the valley
diltiazem, lily of the valley. Either increases toxicity of the other by pharmacodynamic synergism. Minor/Significance Unknown.
- maitake
maitake increases effects of diltiazem by pharmacodynamic synergism. Minor/Significance Unknown.
- metformin
diltiazem will increase the level or effect of metformin by basic (cationic) drug competition for renal tubular clearance. Minor/Significance Unknown.
- metipranolol ophthalmic
metipranolol ophthalmic increases effects of diltiazem by pharmacodynamic synergism. Minor/Significance Unknown.
- octacosanol
octacosanol increases effects of diltiazem by pharmacodynamic synergism. Minor/Significance Unknown.
- ondansetron
diltiazem will increase the level or effect of ondansetron by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown. No dosage adjustment for ondansetron is recommended.
- pancuronium
diltiazem increases effects of pancuronium by pharmacodynamic synergism. Minor/Significance Unknown. Ca Channel Blockers interfere w/Ach release from prejunctional axon.
- rapacuronium
diltiazem increases effects of rapacuronium by pharmacodynamic synergism. Minor/Significance Unknown. Ca Channel Blockers interfere w/Ach release from prejunctional axon.
- reishi
reishi increases effects of diltiazem by pharmacodynamic synergism. Minor/Significance Unknown.
- rocuronium
diltiazem increases effects of rocuronium by pharmacodynamic synergism. Minor/Significance Unknown. Ca Channel Blockers interfere w/Ach release from prejunctional axon.
- succinylcholine
diltiazem increases effects of succinylcholine by pharmacodynamic synergism. Minor/Significance Unknown. Ca Channel Blockers interfere w/Ach release from prejunctional axon.
- sulfamethoxazole
sulfamethoxazole will increase the level or effect of diltiazem by basic (cationic) drug competition for renal tubular clearance. Minor/Significance Unknown.
- tizanidine
tizanidine increases effects of diltiazem by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- treprostinil
treprostinil increases effects of diltiazem by pharmacodynamic synergism. Minor/Significance Unknown.
- vecuronium
diltiazem increases effects of vecuronium by pharmacodynamic synergism. Minor/Significance Unknown. Ca Channel Blockers interfere w/Ach release from prejunctional axon.
- verteporfin
diltiazem increases levels of verteporfin by pharmacodynamic synergism. Minor/Significance Unknown.
- willow bark
diltiazem increases effects of willow bark by unknown mechanism. Minor/Significance Unknown. Enhanced antiplatelet activity.
Adverse Effects
>10%
Edema (2-15%)
Headache (5-12%)
1-10%
Dizziness (3-10%)
AV block (2-8%)
Peripheral edema (2-8%)
Bradyarrhythmia (2-6%)
Headache (1-5%)
Hypotension (2-4%)
Nausea (3%)
Vomiting (2%)
Vasodilation (2-3%)
Extrasystoles (2%)
Flushing (1-2%)
Drug-induced gingival hyperplasia (<2%)
Myalgia (2%)
Diarrhea (1-2%)
Constipation (2-4%)
Bronchitis (1-4%)
Sinus congestion (1-2%)
Dyspnea (1-6%)
Congestion (1-2%)
< 1%
Increased Alkaline phosphatase as well as ALT and AST
CHF
Thrombocytopenia
Toxic epidermal necrolysis
Hemolytic anemia
Photosensitivity
Extrapyramidal symptoms
Syncope
Warnings
Contraindications
Hypersensitivity
Wolff-Parkinson-White syndrome, Lown-Ganong-Levine syndrome, symptomatic severe hypotension (systolic BP <90 mm Hg), sick sinus syndrome (if no pacemaker), 2°/3° (if no pacemaker); heart block
PO: Acute MI and pulmonary congestion
IV: Use in newborns (because of benzyl alcohol), concomitant beta-blocker therapy, cardiogenic shock, ventricular tachycardia (must determine whether origin is supraventricular or ventricular)
Cautions
May cause abnormally slow heart rates or second- or third-degree AV block’ patients with sick sinus syndrome are at increased risk of bradycardia (risk increases with agents known to slow cardiac conduction
Stevens-Johnson syndrome, toxic epidermal necrolusis, erythema multiforme and/or exfoliative dermatitis reported
Significant elevations in liver enzymes such as alkaline phosphatase, LDH, AST (SGOT), ALT (SGPT) and signs of acute hepatic injury reported; reversible upon discontinuation of drug therapy
Mild elevations of transaminases with and without concomitant elevation in alkaline phosphatase and bilirubin observed; elevations were usually resolved even with continued diltiazem treatment
Symptomatic hypotension with or without syncope reported
Peripheral edema occurs within 2-3 weeks of starting therapy
Use with caution in hypertrophic obstructive cariomyopathy, hepatic/renal impairment, left ventricular dysfunction
Concomitant use of diltiazem with beta-blockers or digitalis may result in additive effects on cardiac conduction; sinus bradycardia resulting in hospitalization reported with concurrent use of clonidine and other agents that slow cardiac conduction
May increase the risk of adverse cardiac events in patients with heart failure due to negative inotropic effects (risk directly related to the severity of baseline HF)
Pregnancy & Lactation
Pregnancy category: C
Lactation: Drug enters breast milk; because of risk for serious adverse reactions in nursing infants from diltiazem, a decision should be made whether to discontinue nursing or to discontinue the drug, taking into account the importance of the drug to the mother
Pregnancy Categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk. C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done. D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk. X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist. NA: Information not available.Pharmacology
Mechanism of Action
Nondihydropyridine calcium-channel blocker: Inhibits extracellular calcium ion influx across membranes of myocardial cells and vascular smooth muscle cells, resulting in inhibition of cardiac and vascular smooth muscle contraction and thereby dilating main coronary and systemic arteries; no effect on serum calcium concentrations; substantial inhibitory effects on cardiac conduction system, acting principally at AV node, with some effects at sinus node
Absorption
Bioavailability: 40% (PO)
Onset (hypertension): 30-60 min (IR); 3 min (IV)
Duration (SVT): 1-3 hr (IV bolus); 0.5-10 hr (following discontinuation of continuous IV infusion)
Peak serum time: 2-4 hr (IR); 10-14 hr (ER capsule); 11-18 hr (ER tablet)
Distribution
Protein bound: 70-80%
Vd: 3-13 L/kg
Metabolism
Metabolized via hepatic CYP3A4
Metabolites: Desacetyldiltiazem (active), 25-50% as potent as diltiazem in coronary vasodilation; N-monodesmethyldiltiazem (inactive)
Elimination
Half-life: 3-4.5 hr (IR); 6-9 hr (ER tablet), 5-10 hr (ER capsule); 3-4 hr (single dose IV); 4-5 hr (continuous infusion)
Clearance: 11.8 mL/min/kg
Excretion: Urine (2-4% as unchanged; 6-7% as metabolites), feces
Administration
IV Incompatibilities
Y-site: Allopurinol, amphotericin B, cefepime, cefoperazone, diazepam, furosemide, ketorolac, lansoprazole, pantoprazole, phenytoin, rifampin, thiopental
IV Compatibilities
Solution: D5W, NS
Y-site (partial list): Acetazolamide (may be incompatible at higher concentrations), acyclovir (may be incompatible at higher concentrations), ceftriaxone, ciprofloxacin, clindamycin, digoxin, dobutamine, dopamine, epinephrine, erythromycin, fentanyl, fluconazole, heparin(?), labetalol, lidocaine, lorazepam, meperidine, metoclopramide, metronidazole, midazolam, milrinone, morphine sulfate, nafcillin (may be incompatible at higher concentrations), nitroglycerin, norepinephrine, potassium chloride, sodium bicarbonate, vancomycin
IV Preparation
IV push may be given by using undiluted 5 mg/mL injection
Infusion
- Accepted diluents are D5W, NS, and D5/½NS
- Add 25 mL of 5 mg/mL solution in 100 mL diluent (1 mg/mL solution)
- Add 50 mL of 5 mg/mL solution in 250 mL diluent (0.83 mg/mL solution)
- Add 50 mL of 5 mg/mL solution in 500 mL diluent (0.45 mg/mL solution)
- Dilute 1 monovial (100 mg) in 100 mL diluent (1 mg/mL solution)
- Dilute 2 monovials (200 mg) in 250 mL diluent (0.8 mg/mL solution)
- Dilute 2 monovials (200 mg) in 500 mL diluent (0.4 mg/mL solution)
IV Administration
Give bolus over 2 minutes with continuous ECG and BP monitoring
Response to bolus may require several minutes to reach maximum; response may persist for several hours after infusion is discontinued
Continuous infusion is done via infusion pump
Infusion for >24 hours is not recommended
Storage
Refrigerate liquid injection vials; protect from freezing
May store at room temperature for 1 month
Powder: Store at room temperature; do not freeze
Reconstituted solution stable at room temperature for 24 hours
Images
BRAND | FORM. | UNIT PRICE | PILL IMAGE |
---|---|---|---|
Cartia XT oral - | 180 mg capsule | ![]() | |
Cartia XT oral - | 300 mg capsule | ![]() | |
Cartia XT oral - | 240 mg capsule | ![]() | |
Cartia XT oral - | 120 mg capsule | ![]() | |
Cartia XT oral - | 120 mg capsule | ![]() | |
Cardizem oral - | 60 mg tablet | ![]() | |
Cardizem oral - | 30 mg tablet | ![]() | |
Cardizem oral - | 120 mg tablet | ![]() | |
diltiazem intravenous - | 5 mg/mL vial | ![]() | |
diltiazem intravenous - | 5 mg/mL vial | ![]() | |
diltiazem intravenous - | 5 mg/mL vial | ![]() | |
diltiazem intravenous - | 5 mg/mL vial | ![]() | |
diltiazem intravenous - | 5 mg/mL vial | ![]() | |
diltiazem intravenous - | 5 mg/mL vial | ![]() | |
diltiazem intravenous - | 5 mg/mL vial | ![]() | |
diltiazem intravenous - | 5 mg/mL vial | ![]() | |
diltiazem intravenous - | 5 mg/mL vial | ![]() | |
diltiazem intravenous - | 5 mg/mL vial | ![]() | |
diltiazem intravenous - | 100 mg vial | ![]() | |
diltiazem intravenous - | 100 mg vial | ![]() | |
diltiazem intravenous - | 5 mg/mL vial | ![]() | |
diltiazem intravenous - | 5 mg/mL vial | ![]() | |
diltiazem intravenous - | 5 mg/mL vial | ![]() | |
diltiazem intravenous - | 5 mg/mL vial | ![]() | |
diltiazem intravenous - | 5 mg/mL vial | ![]() | |
diltiazem intravenous - | 5 mg/mL vial | ![]() | |
diltiazem intravenous - | 5 mg/mL vial | ![]() | |
diltiazem intravenous - | 5 mg/mL vial | ![]() | |
diltiazem intravenous - | 5 mg/mL vial | ![]() | |
Tiazac oral - | 420 mg capsule | ![]() | |
Tiazac oral - | 360 mg capsule | ![]() | |
Tiazac oral - | 300 mg capsule | ![]() | |
Tiazac oral - | 120 mg capsule | ![]() | |
Tiazac oral - | 240 mg capsule | ![]() | |
Tiazac oral - | 180 mg capsule | ![]() | |
Cardizem CD oral - | 360 mg capsule | ![]() | |
Cardizem CD oral - | 300 mg capsule | ![]() | |
Cardizem CD oral - | 240 mg capsule | ![]() | |
Cardizem CD oral - | 180 mg capsule | ![]() | |
Cardizem CD oral - | 120 mg capsule | ![]() | |
Matzim LA oral - | 420 mg tablet | ![]() | |
Matzim LA oral - | 180 mg tablet | ![]() | |
Matzim LA oral - | 360 mg tablet | ![]() | |
Matzim LA oral - | 300 mg tablet | ![]() | |
Matzim LA oral - | 240 mg tablet | ![]() | |
DILT-XR oral - | 180 mg capsule | ![]() | |
DILT-XR oral - | 240 mg capsule | ![]() | |
DILT-XR oral - | 120 mg capsule | ![]() | |
Tiadylt ER oral - | 180 mg capsule | ![]() | |
Tiadylt ER oral - | 420 mg capsule | ![]() | |
Tiadylt ER oral - | 300 mg capsule | ![]() | |
Tiadylt ER oral - | 240 mg capsule | ![]() | |
Tiadylt ER oral - | 120 mg capsule | ![]() | |
diltiazem oral - | 300 mg capsule | ![]() | |
diltiazem oral - | 240 mg capsule | ![]() | |
diltiazem oral - | 180 mg capsule | ![]() | |
diltiazem oral - | 120 mg capsule | ![]() | |
diltiazem oral - | 240 mg capsule | ![]() | |
diltiazem oral - | 180 mg capsule | ![]() | |
diltiazem oral - | 120 mg capsule | ![]() | |
diltiazem oral - | 300 mg capsule | ![]() | |
diltiazem oral - | 90 mg capsule | ![]() | |
diltiazem oral - | 60 mg tablet | ![]() | |
diltiazem oral - | 30 mg tablet | ![]() | |
diltiazem oral - | 420 mg tablet | ![]() | |
diltiazem oral - | 300 mg tablet | ![]() | |
diltiazem oral - | 360 mg tablet | ![]() | |
diltiazem oral - | 120 mg tablet | ![]() | |
diltiazem oral - | 240 mg tablet | ![]() | |
diltiazem oral - | 120 mg capsule | ![]() | |
diltiazem oral - | 60 mg tablet | ![]() | |
diltiazem oral - | 60 mg capsule | ![]() | |
diltiazem oral - | 420 mg tablet | ![]() | |
diltiazem oral - | 360 mg tablet | ![]() | |
diltiazem oral - | 180 mg tablet | ![]() | |
diltiazem oral - | 240 mg capsule | ![]() | |
diltiazem oral - | 180 mg capsule | ![]() | |
diltiazem oral - | 90 mg tablet | ![]() | |
diltiazem oral - | 120 mg capsule | ![]() | |
diltiazem oral - | 60 mg tablet | ![]() | |
diltiazem oral - | 30 mg tablet | ![]() | |
diltiazem oral - | 120 mg capsule | ![]() | |
diltiazem oral - | 300 mg capsule | ![]() | |
diltiazem oral - | 300 mg capsule | ![]() | |
diltiazem oral - | 240 mg capsule | ![]() | |
diltiazem oral - | 90 mg capsule | ![]() | |
diltiazem oral - | 30 mg tablet | ![]() | |
diltiazem oral - | 60 mg tablet | ![]() | |
diltiazem oral - | 30 mg tablet | ![]() | |
diltiazem oral - | 120 mg tablet | ![]() | |
diltiazem oral - | 240 mg capsule | ![]() | |
diltiazem oral - | 120 mg capsule | ![]() | |
diltiazem oral - | 240 mg capsule | ![]() | |
diltiazem oral - | 300 mg capsule | ![]() | |
diltiazem oral - | 180 mg capsule | ![]() | |
diltiazem oral - | 90 mg tablet | ![]() | |
diltiazem oral - | 240 mg capsule | ![]() | |
diltiazem oral - | 120 mg capsule | ![]() | |
diltiazem oral - | 180 mg capsule | ![]() | |
diltiazem oral - | 120 mg capsule | ![]() | |
diltiazem oral - | 180 mg tablet | ![]() | |
diltiazem oral - | 120 mg tablet | ![]() | |
diltiazem oral - | 60 mg capsule | ![]() | |
diltiazem oral - | 240 mg capsule | ![]() | |
diltiazem oral - | 120 mg tablet | ![]() | |
diltiazem oral - | 360 mg capsule | ![]() | |
diltiazem oral - | 180 mg capsule | ![]() | |
diltiazem oral - | 360 mg capsule | ![]() | |
diltiazem oral - | 240 mg capsule | ![]() | |
diltiazem oral - | 180 mg capsule | ![]() | |
diltiazem oral - | 120 mg capsule | ![]() | |
diltiazem oral - | 300 mg capsule | ![]() | |
diltiazem oral - | 180 mg capsule | ![]() | |
diltiazem oral - | 120 mg capsule | ![]() | |
diltiazem oral - | 360 mg capsule | ![]() | |
diltiazem oral - | 90 mg tablet | ![]() | |
diltiazem oral - | 300 mg capsule | ![]() | |
diltiazem oral - | 360 mg capsule | ![]() | |
diltiazem oral - | 300 mg tablet | ![]() | |
diltiazem oral - | 120 mg capsule | ![]() | |
diltiazem oral - | 180 mg capsule | ![]() | |
diltiazem oral - | 240 mg tablet | ![]() | |
diltiazem oral - | 420 mg capsule | ![]() | |
diltiazem oral - | 360 mg capsule | ![]() | |
diltiazem oral - | 300 mg capsule | ![]() | |
diltiazem oral - | 180 mg capsule | ![]() | |
diltiazem oral - | 120 mg capsule | ![]() | |
diltiazem oral - | 360 mg capsule | ![]() | |
diltiazem oral - | 360 mg capsule | ![]() | |
diltiazem oral - | 300 mg capsule | ![]() | |
diltiazem oral - | 120 mg capsule | ![]() | |
diltiazem oral - | 120 mg tablet | ![]() | |
diltiazem oral - | 360 mg capsule | ![]() | |
diltiazem oral - | 240 mg capsule | ![]() | |
diltiazem oral - | 180 mg capsule | ![]() | |
Cardizem LA oral - | 420 mg tablet | ![]() | |
Cardizem LA oral - | 360 mg tablet | ![]() | |
Cardizem LA oral - | 300 mg tablet | ![]() | |
Cardizem LA oral - | 240 mg tablet | ![]() | |
Cardizem LA oral - | 180 mg tablet | ![]() | |
Cardizem LA oral - | 120 mg tablet | ![]() | |
Taztia XT oral - | 360 mg capsule | ![]() | |
Taztia XT oral - | 300 mg capsule | ![]() | |
Taztia XT oral - | 240 mg capsule | ![]() | |
Taztia XT oral - | 180 mg capsule | ![]() | |
Taztia XT oral - | 120 mg capsule | ![]() |
Copyright © 2010 First DataBank, Inc.
Patient Handout
diltiazem intravenous
NO MONOGRAPH AVAILABLE AT THIS TIME
USES: Consult your pharmacist.
HOW TO USE: Consult your pharmacist.
SIDE EFFECTS: Consult your pharmacist.In the US -Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.
PRECAUTIONS: Consult your pharmacist.
DRUG INTERACTIONS: Consult your pharmacist.Keep a list of all your medications with you, and share the list with your doctor and pharmacist.
OVERDOSE: If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center.
NOTES: No monograph available at this time.
MISSED DOSE: Consult your pharmacist.
STORAGE: Consult your pharmacist.Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company for more details about how to safely discard your product.
Information last revised July 2016. Copyright(c) 2023 First Databank, Inc.
IMPORTANT: HOW TO USE THIS INFORMATION: This is a summary and does NOT have all possible information about this product. This information does not assure that this product is safe, effective, or appropriate for you. This information is not individual medical advice and does not substitute for the advice of your health care professional. Always ask your health care professional for complete information about this product and your specific health needs.
Formulary
Adding plans allows you to compare formulary status to other drugs in the same class.
To view formulary information first create a list of plans. Your list will be saved and can be edited at any time.
Adding plans allows you to:
- View the formulary and any restrictions for each plan.
- Manage and view all your plans together – even plans in different states.
- Compare formulary status to other drugs in the same class.
- Access your plan list on any device – mobile or desktop.