desipramine and mirtazapine both increase sedation. Use Caution/Monitor.Serious - Use Alternative (1)mirtazapine and desipramine both increase QTc interval. Avoid or Use Alternate Drug.desvenlafaxineSerious - Use Alternative (1)mirtazapine and desvenlafaxine both increase serotonin levels. Avoid or Use Alternate Drug.deutetrabenazineMonitor Closely (1)deutetrabenazine and mirtazapine both increase QTc interval. Use Caution/Monitor. At the maximum recommended dose, deutetrabenazine does not prolong QT interval to a clinically relevant extent. Certain circumstances may increase risk of torsade de pointes and/or sudden death in association with drugs that prolong the QTc interval (eg, bradycardia, hypokalemia or hypomagnesemia, coadministration with other drugs that prolong QTc interval, presence of congenital QT prolongation).dexchlorpheniramineMonitor Closely (1)dexchlorpheniramine and mirtazapine both increase sedation. Use Caution/Monitor.dexfenfluramineMonitor Closely (2)mirtazapine increases and dexfenfluramine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. dexfenfluramine and mirtazapine both increase serotonin levels. Use Caution/Monitor.dexmedetomidineMonitor Closely (1)dexmedetomidine and mirtazapine both increase sedation. Use Caution/Monitor.dexmethylphenidateMonitor Closely (1)mirtazapine increases and dexmethylphenidate decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.dextroamphetamineMonitor Closely (2)mirtazapine increases and dextroamphetamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. dextroamphetamine and mirtazapine both increase serotonin levels. Use Caution/Monitor.dextroamphetamine transdermalMonitor Closely (1)mirtazapine, dextroamphetamine transdermal. Either increases effects of the other by serotonin levels. Modify Therapy/Monitor Closely. Initiate with lower doses and monitor for signs and symptoms of serotonin syndrome, particularly during initiation or dosage increase. If serotonin syndrome occurs, discontinue dextroamphetamine transdermal and concomitant serotonergic drug(s).dextromethorphanMonitor Closely (1)dextromethorphan and mirtazapine both increase serotonin levels. Modify Therapy/Monitor Closely.dextromoramideMonitor Closely (1)dextromoramide and mirtazapine both increase sedation. Use Caution/Monitor.diamorphineMonitor Closely (1)diamorphine and mirtazapine both increase sedation. Use Caution/Monitor.diazepamMonitor Closely (1)diazepam and mirtazapine both increase sedation. Use Caution/Monitor.diazepam intranasalMonitor Closely (1)diazepam intranasal, mirtazapine. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Coadministration may potentiate the CNS-depressant effects of each drug.diethylpropionMonitor Closely (1)mirtazapine increases and diethylpropion decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.difelikefalinMonitor Closely (1)difelikefalin and mirtazapine both increase sedation. Use Caution/Monitor.difenoxin hclMonitor Closely (1)difenoxin hcl and mirtazapine both increase sedation. Use Caution/Monitor.dihydroergotamineMonitor Closely (1)dihydroergotamine and mirtazapine both increase serotonin levels. Use Caution/Monitor.dihydroergotamine intranasalMonitor Closely (1)dihydroergotamine intranasal and mirtazapine both increase serotonin levels. Use Caution/Monitor.dimenhydrinateMonitor Closely (1)dimenhydrinate and mirtazapine both increase sedation. Use Caution/Monitor.diphenhydramineMonitor Closely (1)diphenhydramine and mirtazapine both increase sedation. Use Caution/Monitor.diphenoxylate hclMonitor Closely (1)diphenoxylate hcl and mirtazapine both increase sedation. Use Caution/Monitor.dipipanoneMonitor Closely (1)dipipanone and mirtazapine both increase sedation. Use Caution/Monitor.disopyramideSerious - Use Alternative (1)mirtazapine and disopyramide both increase QTc interval. Avoid or Use Alternate Drug.dobutamineMonitor Closely (1)mirtazapine increases and dobutamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.dofetilideSerious - Use Alternative (1)mirtazapine and dofetilide both increase QTc interval. Avoid or Use Alternate Drug.dolasetronMonitor Closely (1)dolasetron and mirtazapine both increase QTc interval. Use Caution/Monitor.donepezilMonitor Closely (1)donepezil and mirtazapine both increase QTc interval. Use Caution/Monitor.dopamineMonitor Closely (1)mirtazapine increases and dopamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.dopexamineMonitor Closely (1)mirtazapine increases and dopexamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.doxepinMonitor Closely (2)doxepin and mirtazapine both increase serotonin levels. Modify Therapy/Monitor Closely. doxepin and mirtazapine both increase sedation. Use Caution/Monitor.Serious - Use Alternative (1)doxepin and mirtazapine both increase QTc interval. Avoid or Use Alternate Drug.doxylamineMonitor Closely (1)doxylamine and mirtazapine both increase sedation. Use Caution/Monitor.dronedaroneContraindicated (1)mirtazapine and dronedarone both increase QTc interval. Contraindicated.droperidolMonitor Closely (1)droperidol and mirtazapine both increase sedation. Use Caution/Monitor.Serious - Use Alternative (1)mirtazapine and droperidol both increase QTc interval. Avoid or Use Alternate Drug.duloxetineMonitor Closely (1)duloxetine and mirtazapine both increase serotonin levels. Modify Therapy/Monitor Closely.duvelisibMonitor Closely (1)duvelisib will increase the level or effect of mirtazapine 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.efavirenzMonitor Closely (2)efavirenz and mirtazapine both increase QTc interval. Use Caution/Monitor. efavirenz will decrease the level or effect of mirtazapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.elagolixMonitor Closely (1)elagolix decreases levels of mirtazapine 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)eletriptan and mirtazapine both increase serotonin levels. Use Caution/Monitor.eliglustatMonitor Closely (1)eliglustat increases levels of mirtazapine by affecting hepatic enzyme CYP2D6 metabolism. Modify Therapy/Monitor Closely. Monitor therapeutic drug concentrations, as indicated, or consider reducing the dosage of the concomitant drug and titrate to clinical effect.Serious - Use Alternative (1)mirtazapine and eliglustat both increase QTc interval. Avoid or Use Alternate Drug.elvitegravir/cobicistat/emtricitabine/tenofovir DFMonitor Closely (2)elvitegravir/cobicistat/emtricitabine/tenofovir DF increases levels of mirtazapine 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. elvitegravir/cobicistat/emtricitabine/tenofovir DF increases levels of mirtazapine by affecting hepatic enzyme CYP2D6 metabolism. Modify Therapy/Monitor Closely. Cobicistat is a CYP2D6 inhibitor; caution with CYP2D6 substrates for which elevated plasma concentrations are associated with serious and/or life-threatening events.encorafenibMonitor Closely (1)encorafenib, mirtazapine. 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.Serious - Use Alternative (1)encorafenib and mirtazapine both increase QTc interval. Avoid or Use Alternate Drug.entrectinibSerious - Use Alternative (1)entrectinib and mirtazapine both increase QTc interval. Avoid or Use Alternate Drug.enzalutamideMonitor Closely (1)enzalutamide will decrease the level or effect of mirtazapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.ephedrineMonitor Closely (1)mirtazapine increases and ephedrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.epinephrineMonitor Closely (1)mirtazapine increases and epinephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.epinephrine racemicMonitor Closely (1)mirtazapine increases and epinephrine racemic decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.ergotamineMonitor Closely (1)ergotamine and mirtazapine both increase serotonin levels. Use Caution/Monitor.eribulinSerious - Use Alternative (1)eribulin and mirtazapine both increase QTc interval. Avoid or Use Alternate Drug.erythromycin baseSerious - Use Alternative (1)mirtazapine and erythromycin base both increase QTc interval. Avoid or Use Alternate Drug.erythromycin ethylsuccinateSerious - Use Alternative (1)mirtazapine and erythromycin ethylsuccinate both increase QTc interval. Avoid or Use Alternate Drug.erythromycin lactobionateSerious - Use Alternative (1)mirtazapine and erythromycin lactobionate both increase QTc interval. Avoid or Use Alternate Drug.erythromycin stearateSerious - Use Alternative (1)mirtazapine and erythromycin stearate both increase QTc interval. Avoid or Use Alternate Drug.escitalopramMonitor Closely (1)escitalopram and mirtazapine both increase serotonin levels. Modify Therapy/Monitor Closely.Serious - Use Alternative (1)mirtazapine and escitalopram both increase QTc interval. Avoid or Use Alternate Drug.estazolamMonitor Closely (1)estazolam and mirtazapine both increase sedation. Use Caution/Monitor.ethanolMonitor Closely (1)ethanol and mirtazapine both increase sedation. Use Caution/Monitor.Minor (1)ethanol, mirtazapine. Either increases toxicity of the other by pharmacodynamic synergism. Minor/Significance Unknown. Additive CNS depression.etomidateMonitor Closely (1)etomidate and mirtazapine both increase sedation. Use Caution/Monitor.etravirineMonitor Closely (1)etravirine will decrease the level or effect of mirtazapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.eucalyptusMinor (1)eucalyptus and mirtazapine both increase sedation. Minor/Significance Unknown.fedratinibMonitor Closely (2)fedratinib will increase the level or effect of mirtazapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Adjust dose of drugs that are CYP3A4 substrates as necessary. fedratinib will increase the level or effect of mirtazapine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor. Adjust dose of drugs that are CYP2D6 substrates as necessary.fenfluramineMonitor Closely (2)fenfluramine, mirtazapine. Either increases effects of the other by serotonin levels. Use Caution/Monitor. Coadministration with drugs that increase serotoninergic effects may increase the risk of serotonin syndrome. mirtazapine increases and fenfluramine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.fexinidazoleMonitor Closely (1)fexinidazole will increase the level or effect of mirtazapine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.Serious - Use Alternative (2)fexinidazole and mirtazapine both increase QTc interval. Avoid or Use Alternate Drug. Avoid coadministration of fexinidazole with drugs known to block potassium channels or prolong QT interval. fexinidazole will increase the level or effect of mirtazapine 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.fezolinetantContraindicated (1)mirtazapine will increase the level or effect of fezolinetant by affecting hepatic enzyme CYP1A2 metabolism. Contraindicated. Fezolinetant AUC and peak plasma concentration are increased if coadministered with drugs that are weak, moderate, or strong CYP1A2 inhibitorsfinerenoneMonitor Closely (1)mirtazapine 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.fingolimodMonitor Closely (1)fingolimod and mirtazapine both increase QTc interval. Use Caution/Monitor.flecainideSerious - Use Alternative (1)mirtazapine and flecainide both increase QTc interval. Avoid or Use Alternate Drug.flibanserinMonitor Closely (1)mirtazapine 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.fluconazoleSerious - Use Alternative (1)mirtazapine and fluconazole both increase QTc interval. Avoid or Use Alternate Drug.fluoxetineMonitor Closely (1)fluoxetine and mirtazapine both increase serotonin levels. Modify Therapy/Monitor Closely.Serious - Use Alternative (1)mirtazapine and fluoxetine both increase QTc interval. Avoid or Use Alternate Drug.fluphenazineMonitor Closely (1)fluphenazine and mirtazapine both increase sedation. Use Caution/Monitor.Serious - Use Alternative (1)mirtazapine and fluphenazine both increase QTc interval. Avoid or Use Alternate Drug.flurazepamMonitor Closely (1)flurazepam and mirtazapine both increase sedation. Use Caution/Monitor.fluvoxamineMonitor Closely (1)fluvoxamine and mirtazapine both increase serotonin levels. Modify Therapy/Monitor Closely.Serious - Use Alternative (1)mirtazapine and fluvoxamine both increase QTc interval. Avoid or Use Alternate Drug.formoterolMonitor Closely (1)mirtazapine increases and formoterol decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.fosamprenavirMonitor Closely (1)fosamprenavir increases levels of mirtazapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Potential for increased toxicity. .foscarnetSerious - Use Alternative (1)mirtazapine and foscarnet both increase QTc interval. Avoid or Use Alternate Drug.fosphenytoinMonitor Closely (1)fosphenytoin will decrease the level or effect of mirtazapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.fostemsavirMonitor Closely (1)mirtazapine and fostemsavir both increase QTc interval. Use Caution/Monitor. QTc prolongation reported with higher than recommended doses of fostemsavir. frovatriptanMonitor Closely (1)frovatriptan and mirtazapine both increase serotonin levels. Use Caution/Monitor.gabapentinMonitor Closely (1)gabapentin, mirtazapine. Either increases effects of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of CNS depressants can result in serious, life-threatening, and fatal respiratory depression. Use lowest dose possible and monitor for respiratory depression and sedation.gabapentin enacarbilMonitor Closely (1)gabapentin enacarbil, mirtazapine. Either increases effects of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of CNS depressants can result in serious, life-threatening, and fatal respiratory depression. Use lowest dose possible and monitor for respiratory depression and sedation.ganaxoloneMonitor Closely (1)mirtazapine and ganaxolone both increase sedation. Use Caution/Monitor.gemifloxacinMonitor Closely (1)gemifloxacin and mirtazapine both increase QTc interval. Use Caution/Monitor.gemtuzumabMonitor Closely (1)mirtazapine and gemtuzumab both increase QTc interval. Use Caution/Monitor.gilteritinibMonitor Closely (1)gilteritinib and mirtazapine both increase QTc interval. Use Caution/Monitor.givosiranSerious - Use Alternative (2)givosiran will increase the level or effect of mirtazapine by affecting hepatic enzyme CYP1A2 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of sensitive CYP1A2 substrates with givosiran. If unavoidable, decrease the CYP1A2 substrate dosage in accordance with approved product labeling. givosiran will increase the level or effect of mirtazapine by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of sensitive CYP2D6 substrates with givosiran. If unavoidable, decrease the CYP2D6 substrate dosage in accordance with approved product labeling.glasdegibSerious - Use Alternative (1)mirtazapine and glasdegib both increase QTc interval. Avoid or Use Alternate Drug.goserelinMonitor Closely (1)mirtazapine and goserelin both increase QTc interval. Use Caution/Monitor.granisetronMonitor Closely (1)granisetron and mirtazapine both increase QTc interval. Use Caution/Monitor.guanfacineSerious - Use Alternative (1)mirtazapine decreases effects of guanfacine by pharmacodynamic antagonism. Avoid or Use Alternate Drug. Risk of hypertensive urgency.haloperidolMonitor Closely (2)mirtazapine and haloperidol both increase QTc interval. Use Caution/Monitor. haloperidol and mirtazapine both increase sedation. Use Caution/Monitor.histrelinMonitor Closely (1)mirtazapine and histrelin both increase QTc interval. Use Caution/Monitor.hydrocodoneMonitor Closely (1)hydrocodone, mirtazapine. Either increases effects of the other by serotonin levels. Use Caution/Monitor. Coadministration of drugs that affect the serotonergic neurotransmitter system may result in serotonin syndrome. If concomitant use is warranted, carefully observe the patient, particularly during treatment initiation and dose adjustment.hydromorphoneMonitor Closely (1)hydromorphone and mirtazapine both increase sedation. Use Caution/Monitor.hydroxychloroquine sulfateSerious - Use Alternative (1)mirtazapine and hydroxychloroquine sulfate both increase QTc interval. Avoid or Use Alternate Drug.hydroxyzineMonitor Closely (2)hydroxyzine and mirtazapine both increase QTc interval. Use Caution/Monitor. hydroxyzine and mirtazapine both