Closely.Serious - Use Alternative (1)nefazodone will increase the level or effect of mirtazapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.nelfinavirMonitor Closely (1)nelfinavir increases levels of mirtazapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Potential for increased toxicity. .nevirapineMonitor Closely (1)nevirapine will decrease the level or effect of mirtazapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.nilotinibSerious - Use Alternative (1)mirtazapine and nilotinib both increase QTc interval. Avoid or Use Alternate Drug.norepinephrineMonitor Closely (1)mirtazapine increases and norepinephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.nortriptylineMonitor Closely (2)nortriptyline and mirtazapine both increase serotonin levels. Modify Therapy/Monitor Closely. nortriptyline and mirtazapine both increase sedation. Use Caution/Monitor.Serious - Use Alternative (1)mirtazapine and nortriptyline both increase QTc interval. Avoid or Use Alternate Drug.octreotideMonitor Closely (1)mirtazapine and octreotide both increase QTc interval. Use Caution/Monitor.ofloxacinMonitor Closely (1)mirtazapine and ofloxacin both increase QTc interval. Use Caution/Monitor.olanzapineMonitor Closely (3)mirtazapine and olanzapine both increase QTc interval. Use Caution/Monitor. Limited data, including some case reports, suggest that olanzapine may be associated with a significant prolongation of the QTc interval in rare instances olanzapine and mirtazapine both increase sedation. Use Caution/Monitor. olanzapine and mirtazapine both increase QTc interval. Use Caution/Monitor.oliceridineMonitor Closely (1)mirtazapine, oliceridine. Either increases effects of the other by serotonin levels. Modify Therapy/Monitor Closely.olopatadine intranasalSerious - Use Alternative (1)mirtazapine and olopatadine intranasal both increase sedation. Avoid or Use Alternate Drug. Coadministration increases risk of CNS depression, which can lead to additive impairment of psychomotor performance and cause daytime impairment. opium tinctureMonitor Closely (1)opium tincture and mirtazapine both increase sedation. Use Caution/Monitor.orphenadrineMonitor Closely (1)orphenadrine and mirtazapine both increase sedation. Use Caution/Monitor.osilodrostatMonitor Closely (1)osilodrostat and mirtazapine both increase QTc interval. Use Caution/Monitor.oxaliplatinSerious - Use Alternative (1)mirtazapine and oxaliplatin both increase QTc interval. Avoid or Use Alternate Drug.oxazepamMonitor Closely (1)oxazepam and mirtazapine both increase sedation. Use Caution/Monitor.oxycodoneMonitor Closely (1)oxycodone and mirtazapine both increase sedation. Use Caution/Monitor.oxymorphoneMonitor Closely (1)oxymorphone and mirtazapine both increase sedation. Use Caution/Monitor.ozanimodSerious - Use Alternative (1)mirtazapine and ozanimod both increase QTc interval. Avoid or Use Alternate Drug.paliperidoneMonitor Closely (1)paliperidone and mirtazapine both increase sedation. Use Caution/Monitor.Serious - Use Alternative (1)mirtazapine and paliperidone both increase QTc interval. Avoid or Use Alternate Drug.panobinostatSerious - Use Alternative (1)mirtazapine and panobinostat both increase QTc interval. Avoid or Use Alternate Drug.papaveretumMonitor Closely (1)papaveretum and mirtazapine both increase sedation. Use Caution/Monitor.papaverineMonitor Closely (1)mirtazapine and papaverine both increase sedation. Use Caution/Monitor.paroxetineMonitor Closely (2)mirtazapine and paroxetine both increase QTc interval. Use Caution/Monitor. paroxetine and mirtazapine both increase serotonin levels. Modify Therapy/Monitor Closely.pasireotideMonitor Closely (1)mirtazapine and pasireotide both increase QTc interval. Use Caution/Monitor.pazopanibSerious - Use Alternative (1)mirtazapine and pazopanib both increase QTc interval. Avoid or Use Alternate Drug.peginterferon alfa 2bMonitor Closely (1)peginterferon alfa 2b, mirtazapine. Other (see comment). Use Caution/Monitor. Comment: When patients are administered peginterferon alpha-2b with CYP2D6 substrates, the therapeutic effect of these drugs may be altered. Peginterferon alpha-2b may increase or decrease levels of CYP2D6 substrate.pentamidineSerious - Use Alternative (1)mirtazapine and pentamidine both increase QTc interval. Avoid or Use Alternate Drug.pentazocineMonitor Closely (2)pentazocine and mirtazapine both increase sedation. Use Caution/Monitor. mirtazapine and pentazocine both increase serotonin levels. Use Caution/Monitor.pentobarbitalMonitor Closely (1)pentobarbital and mirtazapine both increase sedation. Use Caution/Monitor.perphenazineMonitor Closely (2)perphenazine and mirtazapine both increase sedation. Use Caution/Monitor. mirtazapine and perphenazine both increase QTc interval. Use Caution/Monitor.phendimetrazineMonitor Closely (1)mirtazapine increases and phendimetrazine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.phenelzineSerious - Use Alternative (1)phenelzine and mirtazapine both increase serotonin levels. Avoid or Use Alternate Drug.phenobarbitalMonitor Closely (2)phenobarbital will decrease the level or effect of mirtazapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. phenobarbital and mirtazapine both increase sedation. Use Caution/Monitor.phentermineMonitor Closely (1)mirtazapine increases and phentermine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.phenylephrineMonitor Closely (1)mirtazapine increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.phenylephrine POMonitor Closely (1)mirtazapine increases and phenylephrine PO decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. .phenytoinMonitor Closely (1)phenytoin will decrease the level or effect of mirtazapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.pholcodineMonitor Closely (1)mirtazapine and pholcodine both increase sedation. Use Caution/Monitor.pimavanserinSerious - Use Alternative (1)mirtazapine and pimavanserin both increase QTc interval. Avoid or Use Alternate Drug.pimozideMonitor Closely (1)pimozide and mirtazapine both increase sedation. Use Caution/Monitor.Serious - Use Alternative (1)mirtazapine and pimozide both increase QTc interval. Contraindicated.pirbuterolMonitor Closely (1)mirtazapine increases and pirbuterol decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.pitolisantSerious - Use Alternative (2)mirtazapine decreases effects of pitolisant by Other (see comment). Avoid or Use Alternate Drug. Comment: Pitolisant increases histamine levels in the brain; therefore, H1 receptor antagonists that cross the blood-brain barrier may reduce the efficacy of pitolisant. mirtazapine and pitolisant both increase QTc interval. Avoid or Use Alternate Drug.ponesimodSerious - Use Alternative (1)mirtazapine and ponesimod both increase QTc interval. Avoid or Use Alternate Drug.posaconazoleContraindicated (1)mirtazapine and posaconazole both increase QTc interval. Contraindicated.Serious - Use Alternative (1)posaconazole will increase the level or effect of mirtazapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated.pregabalinMonitor Closely (1)pregabalin, 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.primaquineMonitor Closely (1)mirtazapine and primaquine both increase QTc interval. Use Caution/Monitor.primidoneMonitor Closely (2)primidone will decrease the level or effect of mirtazapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. primidone and mirtazapine both increase sedation. Use Caution/Monitor.procainamideSerious - Use Alternative (1)mirtazapine and procainamide both increase QTc interval. Avoid or Use Alternate Drug.procarbazineContraindicated (1)procarbazine and mirtazapine both increase serotonin levels. Contraindicated.prochlorperazineMonitor Closely (2)mirtazapine and prochlorperazine both decrease QTc interval. Use Caution/Monitor. prochlorperazine and mirtazapine both increase sedation. Use Caution/Monitor.promethazineMonitor Closely (2)mirtazapine and promethazine both decrease QTc interval. Use Caution/Monitor. promethazine and mirtazapine both increase sedation. Use Caution/Monitor.propafenoneSerious - Use Alternative (1)mirtazapine and propafenone both increase QTc interval. Avoid or Use Alternate Drug.propofolMonitor Closely (2)propofol and mirtazapine both increase sedation. Use Caution/Monitor. mirtazapine and propofol both increase QTc interval. Use Caution/Monitor.propylhexedrineMonitor Closely (1)mirtazapine increases and propylhexedrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.protriptylineMonitor Closely (2)protriptyline and mirtazapine both increase serotonin levels. Modify Therapy/Monitor Closely. protriptyline and mirtazapine both increase sedation. Use Caution/Monitor.Serious - Use Alternative (1)mirtazapine and protriptyline both increase QTc interval. Avoid or Use Alternate Drug.quazepamMonitor Closely (1)quazepam and mirtazapine both increase sedation. Use Caution/Monitor.quetiapineMonitor Closely (1)quetiapine and mirtazapine both increase sedation. Use Caution/Monitor.Serious - Use Alternative (1)mirtazapine and quetiapine both increase QTc interval. Avoid or Use Alternate Drug.quinidineSerious - Use Alternative (1)mirtazapine and quinidine both increase QTc interval. Avoid or Use Alternate Drug.quinineSerious - Use Alternative (1)mirtazapine and quinine both increase QTc interval. Avoid or Use Alternate Drug.ramelteonMonitor Closely (1)mirtazapine and ramelteon both increase sedation. Use Caution/Monitor.ranolazineMonitor Closely (1)mirtazapine and ranolazine both increase QTc interval. Use Caution/Monitor.rasagilineContraindicated (1)rasagiline and mirtazapine both increase serotonin levels. Contraindicated. Avoid combination within 14 days of MAOI use.remifentanilMonitor Closely (1)mirtazapine, remifentanil. Either increases toxicity of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Increases risk of serotonin syndrome.remimazolamMonitor Closely (1)remimazolam, mirtazapine. Either increases toxicity of the other by sedation. Modify Therapy/Monitor Closely. Coadministration may result in profound sedation, respiratory depression, coma, and/or death. Continuously monitor vital signs during sedation and recovery period if coadministered. Carefully titrate remimazolam dose if administered with opioid analgesics and/or sedative/hypnotics.ribociclibMonitor Closely (1)ribociclib will increase the level or effect of mirtazapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.Serious - Use Alternative (1)mirtazapine and ribociclib both increase QTc interval. Avoid or Use Alternate Drug.rifabutinMonitor Closely (1)rifabutin will decrease the level or effect of mirtazapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.rifampinMonitor Closely (1)rifampin will decrease the level or effect of mirtazapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.rifapentineMonitor Closely (1)rifapentine will decrease the level or effect of mirtazapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.rilpivirineMonitor Closely (1)mirtazapine and rilpivirine both increase QTc interval. Use Caution/Monitor.risperidoneMonitor Closely (2)risperidone and mirtazapine both increase sedation. Use Caution/Monitor. mirtazapine and risperidone both increase QTc interval. Use Caution/Monitor.ritonavirMonitor Closely (1)ritonavir increases levels of mirtazapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Potential for increased toxicity.rizatriptanMonitor Closely (1)rizatriptan and mirtazapine both increase serotonin levels. Use Caution/Monitor.rolapitantMonitor Closely (1)rolapitant will increase the level or effect of mirtazapine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor. Rolapitant may increase plasma concentrations of CYP2D6 substrates for at least 28 days following rolapitant administration.romidepsinMonitor Closely (1)mirtazapine and romidepsin both increase QTc interval. Use Caution/Monitor.ropeginterferon alfa 2bSerious - Use Alternative (1)ropeginterferon alfa 2b and mirtazapine both increase Other (see comment). Avoid or Use Alternate Drug. Narcotics, hypnotics or sedatives can produce additive neuropsychiatric side effects. Avoid use and monitor patients receiving the combination for effects of excessive CNS toxicity.ruxolitinibMinor (1)mirtazapine will increase the level or effect of ruxolitinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.ruxolitinib topicalMinor (1)mirtazapine will increase the level or effect of ruxolitinib topical by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.sageMinor (1)mirtazapine and sage both increase sedation. Minor/Significance Unknown.salmeterolMonitor Closely (1)mirtazapine increases and salmeterol decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.SAMeMonitor Closely (1)mirtazapine and SAMe both increase serotonin levels. Use Caution/Monitor.saquinavirMonitor Closely (2)saquinavir will increase the level or effect of mirtazapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. mirtazapine and saquinavir both increase QTc interval. Use Caution/Monitor.scullcapMonitor Closely (1)mirtazapine and scullcap both increase sedation. Use Caution/Monitor.secobarbitalMonitor Closely (1)secobarbital and mirtazapine both increase sedation. Use Caution/Monitor.selegilineContraindicated (1)selegiline and mirtazapine both increase serotonin levels. Contraindicated. At least 14 days should elapse between discontinuation of selegiline and initiation of mirtazapine.selegiline transdermalMonitor Closely (1)selegiline transdermal and mirtazapine both increase serotonin levels. Modify Therapy/Monitor Closely.selpercatinibSerious - Use Alternative (1)mirtazapine and selpercatinib both increase QTc interval. Avoid or Use Alternate Drug.sertralineMonitor Closely (2)sertraline and mirtazapine both increase serotonin levels. Modify Therapy/Monitor Closely. mirtazapine and sertraline both increase QTc interval. Use Caution/Monitor.sevofluraneMonitor Closely (1)sevoflurane and mirtazapine both increase sedation. Use Caution/Monitor.Serious - Use Alternative (1)sevoflurane and mirtazapine both increase QTc interval. Avoid or Use Alternate Drug.shepherd's purseMonitor Closely (1)mirtazapine and shepherd's purse both increase sedation. Use Caution/Monitor.siponimodSerious - Use Alternative (1)mirtazapine and siponimod both increase QTc interval. Avoid or Use Alternate Drug.sodium oxybateSerious - Use Alternative (1)mirtazapine, sodium oxybate. Either increases effects of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Profound sedation, respiratory depression, coma, and death may result if coadministered. Reserve concomitant prescribing of these drugs in patients for whom other treatment options are inadequate. Limit dosages and durations to the minimum required. Monitor closely for signs of respiratory depression and sedation.solifenacinMonitor Closely (1)mirtazapine and solifenacin both increase QTc interval. Use Caution/Monitor.sorafenibSerious - Use Alternative (1)mirtazapine and sorafenib both increase QTc interval. Avoid or Use Alternate Drug.sotalolSerious - Use Alternative (1)mirtazapine and sotalol both increase QTc interval. Avoid or Use Alternate Drug.St John's WortMonitor Closely (1)mirtazapine and St John's Wort both increase serotonin levels. Modify Therapy/Monitor Closely.stiripentolMonitor Closely (3)stiripentol, mirtazapine. Either increases effects of the other by sedation. Use Caution/Monitor. Concomitant use stiripentol with other CNS depressants, including alcohol, may increase the risk of sedation and somnolence. stiripentol, mirtazapine. affecting hepatic enzyme CYP1A2 metabolism. Modify Therapy/Monitor Closely. Stiripentol is a CYP1A2 inhibitor and inducer. Monitor CYP1A2 substrates coadministered with stiripentol for increased or decreased effects. CYP1A2 substrates may require dosage adjustment. stiripentol, mirtazapine. 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.sufentanilMonitor Closely (1)sufentanil and mirtazapine both increase sedation. Use Caution/Monitor.sufentanil SLMonitor Closely (1)sufentanil SL, 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.sumatriptanMonitor Closely (1)sumatriptan and mirtazapine both increase serotonin levels. Use Caution/Monitor.sumatriptan intranasalMonitor Closely (1)sumatriptan intranasal and mirtazapine both increase serotonin levels. Use Caution/Monitor.sunitinibMonitor Closely (1)mirtazapine and sunitinib both increase QTc interval. Use Caution/Monitor.Serious - Use Alternative (1)sunitinib and mirtazapine both increase QTc interval. Avoid or Use Alternate Drug.tacrolimusMonitor Closely (1)mirtazapine and tacrolimus both increase QTc interval. Use Caution/Monitor.tapentadolMonitor Closely (2)mirtazapine and tapentadol both increase serotonin levels. Modify Therapy/Monitor Closely. tapentadol and mirtazapine both increase sedation. Use Caution/Monitor.tazemetostatMonitor Closely (2)tazemetostat will decrease the level or effect of mirtazapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. mirtazapine will increase the level or effect of tazemetostat