unspecified interaction mechanism. Minor/Significance Unknown. Estrogens and progestins may decr tricyclic antidepressant effects, while increasing TCA plasma concentration and adverse effects.etomidateMonitor Closely (1)etomidate and amitriptyline both increase sedation. Use Caution/Monitor.Minor (1)etomidate, amitriptyline. Mechanism: unspecified interaction mechanism. Minor/Significance Unknown. Risk of arrhythmias or hypotension.etravirineMonitor Closely (1)etravirine will increase the level or effect of amitriptyline by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.Minor (1)etravirine will decrease the level or effect of amitriptyline by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.eucalyptusMinor (1)amitriptyline and eucalyptus both increase sedation. Minor/Significance Unknown.ezogabineMonitor Closely (1)ezogabine, amitriptyline. Either increases toxicity of the other by QTc interval. Use Caution/Monitor. Slight and transient QT-prolongation observed with ezogabine, particularly when dose titrated to 1200 mg/day. QT interval should be monitored when ezogabine is prescribed with agents known to increase QT interval.fedratinibMonitor Closely (1)fedratinib will increase the level or effect of amitriptyline by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor. Adjust dose of drugs that are CYP2D6 substrates as necessary.felbamateMonitor Closely (1)felbamate will increase the level or effect of amitriptyline by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.felodipineMonitor Closely (1)felodipine will increase the level or effect of amitriptyline by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor.Minor (1)felodipine will increase the level or effect of amitriptyline by affecting hepatic enzyme CYP2C19 metabolism. Minor/Significance Unknown.fenfluramineMonitor Closely (3)fenfluramine, amitriptyline. 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. amitriptyline and fenfluramine both increase serotonin levels. Modify Therapy/Monitor Closely. amitriptyline increases and fenfluramine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.Serious - Use Alternative (1)amitriptyline, fenfluramine. Other (see comment). Avoid or Use Alternate Drug. Comment: Tricyclic antidepressants increase or decrease effects of sympathomimetics, by blocking reuptake of NE, or blocking uptake of indirect sympathomimetics into the adrenergic neuron.fesoterodineMonitor Closely (1)fesoterodine and amitriptyline both decrease cholinergic effects/transmission. Modify Therapy/Monitor Closely.fexinidazoleSerious - Use Alternative (1)fexinidazole and amitriptyline both increase QTc interval. Avoid or Use Alternate Drug. Avoid coadministration of fexinidazole with drugs known to block potassium channels or prolong QT interval.fezolinetantContraindicated (1)amitriptyline 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 inhibitorsfingolimodMonitor Closely (1)fingolimod and amitriptyline both increase QTc interval. Use Caution/Monitor.flavoxateMonitor Closely (1)flavoxate and amitriptyline both decrease cholinergic effects/transmission. Modify Therapy/Monitor Closely.flecainideMonitor Closely (1)amitriptyline and flecainide both increase QTc interval. Modify Therapy/Monitor Closely.fluconazoleMonitor Closely (2)fluconazole will increase the level or effect of amitriptyline by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor. fluconazole will increase the level or effect of amitriptyline by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.Serious - Use Alternative (1)amitriptyline and fluconazole both increase QTc interval. Avoid or Use Alternate Drug.fludrocortisoneMinor (1)fludrocortisone will decrease the level or effect of amitriptyline by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.fluoxetineMonitor Closely (1)amitriptyline and fluoxetine both increase QTc interval. Modify Therapy/Monitor Closely.Serious - Use Alternative (2)fluoxetine and amitriptyline both increase serotonin levels. Avoid or Use Alternate Drug. fluoxetine will increase the level or effect of amitriptyline by affecting hepatic enzyme CYP2C19 metabolism. Avoid or Use Alternate Drug.fluphenazineMonitor Closely (1)fluphenazine and amitriptyline both increase sedation. Use Caution/Monitor.Serious - Use Alternative (1)fluphenazine and amitriptyline both increase QTc interval. Avoid or Use Alternate Drug.Minor (2)amitriptyline, fluphenazine. Either increases levels of the other by decreasing metabolism. Minor/Significance Unknown. Additive anticholinergic effects. amitriptyline, fluphenazine. Either increases levels of the other by pharmacodynamic synergism. Minor/Significance Unknown. Additive anticholinergic effects.flurazepamMonitor Closely (1)flurazepam and amitriptyline both increase sedation. Use Caution/Monitor.fluvoxamineMonitor Closely (1)fluvoxamine and amitriptyline both increase QTc interval. Modify Therapy/Monitor Closely.Serious - Use Alternative (1)fluvoxamine and amitriptyline both increase serotonin levels. Avoid or Use Alternate Drug.formoterolMonitor Closely (1)amitriptyline increases and formoterol decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.Serious - Use Alternative (2)amitriptyline and formoterol both increase QTc interval. Avoid or Use Alternate Drug. amitriptyline, formoterol. Other (see comment). Avoid or Use Alternate Drug. Comment: Tricyclic antidepressants increase or decrease effects of sympathomimetics, by blocking reuptake of NE, or blocking uptake of indirect sympathomimetics into the adrenergic neuron.fosamprenavirMonitor Closely (1)fosamprenavir will increase the level or effect of amitriptyline by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.Serious - Use Alternative (1)fosamprenavir increases levels of amitriptyline by decreasing metabolism. Avoid or Use Alternate Drug.fosaprepitantMonitor Closely (1)fosaprepitant will increase the level or effect of amitriptyline by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.foscarnetMonitor Closely (1)amitriptyline and foscarnet both increase QTc interval. Modify Therapy/Monitor Closely.fosphenytoinMonitor Closely (2)fosphenytoin will decrease the level or effect of amitriptyline by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor. fosphenytoin will decrease the level or effect of amitriptyline by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.fostemsavirMonitor Closely (1)amitriptyline and fostemsavir both increase QTc interval. Use Caution/Monitor. QTc prolongation reported with higher than recommended doses of fostemsavir. frovatriptanMonitor Closely (1)frovatriptan and amitriptyline both increase serotonin levels. Modify Therapy/Monitor Closely.gabapentinMonitor Closely (1)gabapentin, amitriptyline. 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, amitriptyline. 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.galantamineMonitor Closely (1)galantamine increases and amitriptyline decreases cholinergic effects/transmission. Effect of interaction is not clear, use caution. Modify Therapy/Monitor Closely.ganaxoloneMonitor Closely (1)amitriptyline and ganaxolone both increase sedation. Use Caution/Monitor.gemifloxacinMonitor Closely (1)gemifloxacin and amitriptyline both increase QTc interval. Use Caution/Monitor.gilteritinibMonitor Closely (1)gilteritinib and amitriptyline both increase QTc interval. Use Caution/Monitor.givosiranSerious - Use Alternative (1)givosiran will increase the level or effect of amitriptyline 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.glecaprevir/pibrentasvirMonitor Closely (1)glecaprevir/pibrentasvir will increase the level or effect of amitriptyline by P-glycoprotein (MDR1) efflux transporter. Modify Therapy/Monitor Closely.glimepirideMinor (1)amitriptyline increases effects of glimepiride by pharmacodynamic synergism. Minor/Significance Unknown.glipizideMinor (1)amitriptyline increases effects of glipizide by pharmacodynamic synergism. Minor/Significance Unknown.glyburideMinor (1)amitriptyline increases effects of glyburide by pharmacodynamic synergism. Minor/Significance Unknown.glycopyrrolateMonitor Closely (2)glycopyrrolate and amitriptyline both decrease cholinergic effects/transmission. Modify Therapy/Monitor Closely. amitriptyline increases levels of glycopyrrolate by unknown mechanism. Use Caution/Monitor.glycopyrrolate inhaledMonitor Closely (2)glycopyrrolate inhaled and amitriptyline both decrease cholinergic effects/transmission. Modify Therapy/Monitor Closely. amitriptyline increases levels of glycopyrrolate inhaled by unknown mechanism. Use Caution/Monitor.glycopyrronium tosylate topicalMonitor Closely (1)glycopyrronium tosylate topical, amitriptyline. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Coadministration of glycopyrronium tosylate topical with other anticholinergic medications may result in additive anticholinergic adverse effects.granisetronSerious - Use Alternative (2)granisetron, amitriptyline. Either increases toxicity of the other by serotonin levels. Avoid or Use Alternate Drug. granisetron and amitriptyline both increase QTc interval. Avoid or Use Alternate Drug.grapefruitMonitor Closely (1)grapefruit will increase the level or effect of amitriptyline by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.griseofulvinMinor (1)griseofulvin will decrease the level or effect of amitriptyline by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.guanfacineSerious - Use Alternative (1)amitriptyline decreases effects of guanfacine by Other (see comment). Avoid or Use Alternate Drug. Comment: Inhibition of uptake by adrenergic neurons.haloperidolMonitor Closely (1)haloperidol and amitriptyline both increase sedation. Use Caution/Monitor.Serious - Use Alternative (1)amitriptyline and haloperidol both increase QTc interval. Avoid or Use Alternate Drug.henbaneMonitor Closely (1)henbane and amitriptyline both decrease cholinergic effects/transmission. Use Caution/Monitor.homatropineMonitor Closely (1)homatropine and amitriptyline both decrease cholinergic effects/transmission. Modify Therapy/Monitor Closely.huperzine AMonitor Closely (1)huperzine A increases and amitriptyline decreases cholinergic effects/transmission. Effect of interaction is not clear, use caution. Use Caution/Monitor.hydrocodoneMonitor Closely (1)hydrocodone, amitriptyline. 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.hydrocortisoneMinor (1)hydrocortisone will decrease the level or effect of amitriptyline by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.hydromorphoneMonitor Closely (1)hydromorphone and amitriptyline both increase sedation. Use Caution/Monitor.hydroxychloroquine sulfateSerious - Use Alternative (1)hydroxychloroquine sulfate and amitriptyline both increase QTc interval. Avoid or Use Alternate Drug.hydroxyprogesterone caproate (DSC)Minor (1)hydroxyprogesterone caproate (DSC), amitriptyline. Mechanism: unspecified interaction mechanism. Minor/Significance Unknown. Estrogens and progestins may decr tricyclic antidepressant effects, while increasing TCA plasma concentration and adverse effects.hydroxyzineMonitor Closely (2)hydroxyzine and amitriptyline both increase QTc interval. Use Caution/Monitor. hydroxyzine and amitriptyline both increase sedation. Use Caution/Monitor.hyoscyamineMonitor Closely (1)hyoscyamine and amitriptyline both decrease cholinergic effects/transmission. Use Caution/Monitor.hyoscyamine sprayMonitor Closely (1)hyoscyamine spray and amitriptyline both decrease cholinergic effects/transmission. Use Caution/Monitor.ibutilideContraindicated (1)amitriptyline and ibutilide both increase QTc interval. Contraindicated.iloperidoneMonitor Closely (2)amitriptyline and iloperidone both increase QTc interval. Modify Therapy/Monitor Closely. iloperidone and amitriptyline both increase sedation. Use Caution/Monitor.imipramineMonitor Closely (2)amitriptyline and imipramine both decrease cholinergic effects/transmission. Use Caution/Monitor. amitriptyline and imipramine both increase sedation. Use Caution/Monitor.Serious - Use Alternative (2)amitriptyline and imipramine both increase QTc interval. Avoid or Use Alternate Drug. amitriptyline and imipramine both increase serotonin levels. Avoid or Use Alternate Drug.indacaterol, inhaledMonitor Closely (1)indacaterol, inhaled, amitriptyline. QTc interval. Use Caution/Monitor. Indacaterol should be administered with extreme caution to patients treated with TCAs. Drugs that are known to prolong the QTc interval may have an increased the risk of ventricular arrhythmias.indapamideContraindicated (1)amitriptyline and indapamide both increase QTc interval. Contraindicated.indinavirMonitor Closely (1)indinavir will increase the level or effect of amitriptyline by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor.insulin aspartMinor (1)amitriptyline increases effects of insulin aspart by pharmacodynamic synergism. Minor/Significance Unknown.insulin detemirMinor (1)amitriptyline increases effects of insulin detemir by pharmacodynamic synergism. Minor/Significance Unknown.insulin glargineMinor (1)amitriptyline increases effects of insulin glargine by pharmacodynamic synergism. Minor/Significance Unknown.insulin glulisineMinor (1)amitriptyline increases effects of insulin glulisine by pharmacodynamic synergism. Minor/Significance Unknown.insulin lisproMinor (1)amitriptyline increases effects of insulin lispro by pharmacodynamic synergism. Minor/Significance Unknown.insulin NPHMinor (1)amitriptyline increases effects of insulin NPH by pharmacodynamic synergism. Minor/Significance Unknown.insulin regular humanMinor (1)amitriptyline increases effects of insulin regular human by pharmacodynamic synergism. Minor/Significance Unknown.iobenguane I 123Contraindicated (1)amitriptyline decreases effects of iobenguane I 123 by pharmacodynamic antagonism. Contraindicated. If clinically appropriate, discontinue drugs that decrease uptake of NE for at least 5 half-lives; may cause false-negative imaging results.iobenguane I 131Serious - Use Alternative (1)amitriptyline will decrease the level or effect of iobenguane I 131 by Other (see comment). Avoid or Use Alternate Drug. Based on the mechanism of action of iobenguane, drugs that reduce catecholamine uptake or that deplete catecholamine stores may interfere with iobenguane uptake into cells, and thus, reduce iobenguane efficacy. Discontinue interfering drugs for at least 5 half-lives before administration of either the dosimetry or an iobenguane dose. Do not administer these drugs until at least 7 days after each iobenguane dose.ipratropiumMonitor Closely (1)ipratropium and amitriptyline both decrease cholinergic effects/transmission. Use Caution/Monitor. Due to the poor systemic absorption of ipratropium, interaction unlikely at regularly recommended dosages.isocarboxazidContraindicated (1)isocarboxazid and amitriptyline both increase serotonin levels. Contraindicated.isofluraneMonitor Closely (1)isoflurane and amitriptyline both increase QTc interval. Use Caution/Monitor.isoniazidMonitor Closely (2)amitriptyline and isoniazid both increase serotonin levels. Modify Therapy/Monitor Closely. isoniazid will increase the level or effect of amitriptyline by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.Minor (1)isoniazid will increase the level or effect of amitriptyline by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.isoproterenolMonitor Closely (1)amitriptyline increases and isoproterenol decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.Serious - Use Alternative (1)amitriptyline, isoproterenol. Other (see comment). Avoid or Use Alternate Drug. Comment: Tricyclic antidepressants increase or decrease effects of sympathomimetics, by blocking reuptake of NE, or blocking uptake of indirect sympathomimetics into the adrenergic neuron.Minor (1)isoproterenol, amitriptyline. Mechanism: unknown. Minor/Significance Unknown. Risk of cardiac arrhythmias.istradefyllineMonitor Closely (1)istradefylline will increase the level or effect of amitriptyline 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.itraconazoleMonitor Closely (2)itraconazole will increase the level or effect of amitriptyline by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor. itraconazole and amitriptyline both increase QTc interval. Use Caution/Monitor.Minor (1)itraconazole will increase the level or effect of amitriptyline by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.ivacaftorMonitor Closely (1)ivacaftor increases levels of amitriptyline by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor. Ivacaftor and its M1 metabolite has the potential to inhibit P-gp; may significantly increase systemic exposure to sensitive P-gp substrates with a narrow therapeutic index.ivosidenibSerious - Use Alternative (1)ivosidenib and amitriptyline both increase QTc interval. Avoid or Use Alternate Drug. Avoid coadministration of