by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.dextroamphetamineMinor (1)darifenacin will increase the level or effect of dextroamphetamine by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.dextromethorphanMinor (1)darifenacin will increase the level or effect of dextromethorphan by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.DHEA, herbalMonitor Closely (1)DHEA, herbal will increase the level or effect of darifenacin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.diazepamMonitor Closely (1)darifenacin will increase the level or effect of diazepam by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.dicyclomineMonitor Closely (1)darifenacin and dicyclomine both decrease cholinergic effects/transmission. Use Caution/Monitor.digoxinMonitor Closely (1)darifenacin increases levels of digoxin by unspecified interaction mechanism. Use Caution/Monitor.dihydroergotamineSerious - Use Alternative (1)darifenacin will increase the level or effect of dihydroergotamine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.dihydroergotamine intranasalSerious - Use Alternative (1)darifenacin will increase the level or effect of dihydroergotamine intranasal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.diltiazemMonitor Closely (1)diltiazem will increase the level or effect of darifenacin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.dimenhydrinateMinor (1)dimenhydrinate increases toxicity of darifenacin by pharmacodynamic synergism. Minor/Significance Unknown. Additive anticholinergic effects.diphenhydramineMonitor Closely (1)darifenacin and diphenhydramine both decrease cholinergic effects/transmission. Use Caution/Monitor.disopyramideMinor (1)darifenacin will increase the level or effect of disopyramide by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.docetaxelMinor (1)darifenacin will increase the level or effect of docetaxel by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.donepezilMonitor Closely (1)donepezil increases and darifenacin decreases cholinergic effects/transmission. Effect of interaction is not clear, use caution. Use Caution/Monitor.Minor (3)darifenacin will increase the level or effect of donepezil by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown. darifenacin will increase the level or effect of donepezil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown. donepezil decreases effects of darifenacin by pharmacodynamic antagonism. Minor/Significance Unknown.donepezil transdermalMonitor Closely (1)donepezil transdermal, darifenacin. Either decreases effects of the other by pharmacodynamic antagonism. Use Caution/Monitor.dosulepinMonitor Closely (1)darifenacin and dosulepin both decrease cholinergic effects/transmission. Use Caution/Monitor.doxepinMonitor Closely (2)darifenacin and doxepin both decrease cholinergic effects/transmission. Use Caution/Monitor. darifenacin will increase the level or effect of doxepin by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.dronedaroneMonitor Closely (1)dronedarone will increase the level or effect of darifenacin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.Serious - Use Alternative (1)darifenacin will increase the level or effect of dronedarone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.droperidolMonitor Closely (3)darifenacin decreases levels of droperidol by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. darifenacin decreases levels of droperidol by pharmacodynamic antagonism. Use Caution/Monitor. droperidol increases effects of darifenacin by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.duloxetineMonitor Closely (1)darifenacin will increase the level or effect of duloxetine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.dutasterideMinor (1)darifenacin will increase the level or effect of dutasteride by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.duvelisibMonitor Closely (1)duvelisib will increase the level or effect of darifenacin by affecting hepatic enzyme CYP2E1 metabolism. Modify Therapy/Monitor Closely. will increase the level or effect ofechothiophate iodideMonitor Closely (1)echothiophate iodide increases and darifenacin decreases cholinergic effects/transmission. Effect of interaction is not clear, use caution. Use Caution/Monitor.efavirenzMonitor Closely (1)efavirenz will decrease the level or effect of darifenacin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.Minor (1)darifenacin will increase the level or effect of efavirenz by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.elagolixMonitor Closely (1)elagolix will decrease the level or effect of darifenacin 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.eletriptanMonitor Closely (1)darifenacin will increase the level or effect of eletriptan by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.eliglustatContraindicated (1)darifenacin increases levels of eliglustat by affecting hepatic enzyme CYP2D6 metabolism. Contraindicated. If coadministered with strong or moderate CYP2D6 inhibitors, reduce eliglustat dose from 84 mg BID to 84 mg once daily in extensive and intermediate metabolizers; eliglustat is contraindiated if strong or moderate CYP2D6 inhibitors are given concomitantly with strong or moderate CYP3A inhibitors.elvitegravir/cobicistat/emtricitabine/tenofovir DFMonitor Closely (1)elvitegravir/cobicistat/emtricitabine/tenofovir DF increases levels of darifenacin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Cobicistat is a CYP3A4 inhibitor; contraindicated with CYP3A4 substrates for which elevated plasma concentrations are associated with serious and/or life-threatening events.encainideMinor (1)darifenacin will increase the level or effect of encainide by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.encorafenibMonitor Closely (1)encorafenib, darifenacin. 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.enzalutamideMonitor Closely (1)enzalutamide will decrease the level or effect of darifenacin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.eplerenoneMinor (1)darifenacin will increase the level or effect of eplerenone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.ergotamineSerious - Use Alternative (1)darifenacin will increase the level or effect of ergotamine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.erlotinibMonitor Closely (1)darifenacin will increase the level or effect of erlotinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.erythromycin baseSerious - Use Alternative (2)darifenacin 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 darifenacin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.erythromycin ethylsuccinateSerious - Use Alternative (2)erythromycin ethylsuccinate will increase the level or effect of darifenacin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. darifenacin will increase the level or effect of erythromycin ethylsuccinate by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.erythromycin lactobionateSerious - Use Alternative (2)erythromycin lactobionate will increase the level or effect of darifenacin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. darifenacin will increase the level or effect of erythromycin lactobionate by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.erythromycin stearateSerious - Use Alternative (2)erythromycin stearate will increase the level or effect of darifenacin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. darifenacin will increase the level or effect of erythromycin stearate by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.eslicarbazepine acetateMonitor Closely (1)eslicarbazepine acetate will decrease the level or effect of darifenacin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.esomeprazoleMinor (1)darifenacin will decrease the level or effect of esomeprazole by Other (see comment). Minor/Significance Unknown. Effectiveness of proton pump inhibitors may be decreased theoretically if administered with other antisecretory agentsestradiolMonitor Closely (1)darifenacin will increase the level or effect of estradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.estrogens conjugated syntheticMonitor Closely (1)darifenacin will increase the level or effect of estrogens conjugated synthetic by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.estrogens esterifiedMonitor Closely (1)darifenacin will increase the level or effect of estrogens esterified by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.estropipateMonitor Closely (1)darifenacin will increase the level or effect of estropipate by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.etonogestrelMonitor Closely (1)darifenacin will increase the level or effect of etonogestrel by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.etravirineMonitor Closely (2)darifenacin 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 darifenacin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.eucalyptusMinor (1)darifenacin will increase the level or effect of eucalyptus by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.everolimusSerious - Use Alternative (1)darifenacin will increase the level or effect of everolimus by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.fedratinibMonitor Closely (1)fedratinib will increase the level or effect of darifenacin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Adjust dose of drugs that are CYP3A4 substrates as necessary.felodipineMonitor Closely (1)darifenacin will increase the level or effect of felodipine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.fesoterodineMonitor Closely (2)darifenacin will increase the level or effect of fesoterodine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. darifenacin and fesoterodine both decrease cholinergic effects/transmission. Use Caution/Monitor.Minor (1)darifenacin will increase the level or effect of fesoterodine by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.fexinidazoleSerious - Use Alternative (1)fexinidazole will increase the level or effect of darifenacin 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. finasterideMinor (1)darifenacin will increase the level or effect of finasteride by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.finerenoneMonitor Closely (1)darifenacin will increase the level or effect of finerenone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Monitor serum potassium during initiation and dosage adjustment of either finererone or weak CYP3A4 inhibitors. Adjust finererone dosage as needed.flavoxateMonitor Closely (1)darifenacin and flavoxate both decrease cholinergic effects/transmission. Use Caution/Monitor.flecainideMonitor Closely (1)darifenacin will increase the level or effect of flecainide by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.flibanserinMonitor Closely (1)darifenacin will increase the level or effect of flibanserin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Increased flibanserin adverse effects may occur if coadministered with multiple weak CYP3A4 inhibitors.fluconazoleMonitor Closely (1)fluconazole will increase the level or effect of darifenacin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.fludrocortisoneMonitor Closely (1)darifenacin will increase the level or effect of fludrocortisone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.fluoxetineMinor (1)darifenacin will increase the level or effect of fluoxetine by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.fluphenazineMonitor Closely (3)darifenacin decreases levels of fluphenazine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. darifenacin decreases levels of fluphenazine by pharmacodynamic antagonism. Use Caution/Monitor. fluphenazine increases effects of darifenacin by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.Minor (1)darifenacin will increase the level or effect of fluphenazine by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.fluvoxamineMonitor Closely (1)fluvoxamine will increase the level or effect of darifenacin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.fosamprenavirMonitor Closely (2)darifenacin will increase the level or effect of fosamprenavir by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. fosamprenavir will increase the level or effect of darifenacin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.fosaprepitantMonitor Closely (2)fosaprepitant will increase the level or effect of darifenacin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. darifenacin will increase the level or effect of fosaprepitant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.fosphenytoinMonitor Closely (1)fosphenytoin will decrease the level or effect of darifenacin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.galantamineMonitor Closely (1)galantamine increases and darifenacin decreases cholinergic effects/transmission. Effect of interaction is not clear, use caution. Use Caution/Monitor.Minor (3)darifenacin will increase the level or effect of galantamine by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown. darifenacin will increase the level or effect of galantamine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown. galantamine decreases effects of darifenacin by pharmacodynamic antagonism. Minor/Significance Unknown.glycopyrrolateMonitor Closely (1)darifenacin and glycopyrrolate both decrease cholinergic effects/transmission. Use Caution/Monitor.glycopyrrolate inhaledMonitor Closely (1)darifenacin and glycopyrrolate inhaled both decrease cholinergic effects/transmission. Use Caution/Monitor.glycopyrronium tosylate topicalSerious - Use Alternative (1)glycopyrronium tosylate topical, darifenacin. Either increases effects of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Coadministration of glycopyrronium tosylate topical with other anticholinergic medications may result in additive anticholinergic adverse effects.grapefruitMonitor Closely (1)grapefruit will increase the level or effect of darifenacin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.griseofulvinMonitor Closely (1)griseofulvin will decrease the level or effect of darifenacin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.haloperidolMonitor Closely (4)darifenacin will increase the level or effect of haloperidol by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor. darifenacin decreases levels of haloperidol by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. darifenacin decreases levels of haloperidol by pharmacodynamic antagonism. Use Caution/Monitor. haloperidol increases effects of darifenacin by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.henbaneMonitor Closely (1)darifenacin and henbane both decrease cholinergic effects/transmission. Use Caution/Monitor.homatropineMonitor Closely (1)darifenacin and homatropine both decrease cholinergic effects/transmission. Use Caution/Monitor.huperzine AMonitor Closely (1)huperzine A increases and darifenacin decreases cholinergic effects/transmission. Effect of interaction is not clear, use caution. Use Caution/Monitor.hydrocodoneMonitor Closely (1)darifenacin will increase the level or effect of hydrocodone by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor. Hydromorphone (<3% of the circulating parent hydrocodone) is mainly formed by CYP2D6 mediated O-demethylation of hydrocodone. Hydromorphone may contribute to the total analgesic effect of hydrocodone.hydrocortisoneMonitor Closely (1)darifenacin will increase the level or effect of hydrocortisone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.hydromorphoneMonitor Closely (1)darifenacin will increase the level or effect of hydromorphone by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.hydroxyprogesterone caproate (DSC)Monitor Closely (1)darifenacin will increase the level or effect of hydroxyprogesterone caproate (DSC)