decreases cholinergic effects/transmission. Effect of interaction is not clear, use caution. Use Caution/Monitor.hydrocodoneMonitor Closely (1)hydrocodone, nortriptyline. 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 nortriptyline both increase sedation. Use Caution/Monitor.hydroxychloroquine sulfateSerious - Use Alternative (1)hydroxychloroquine sulfate and nortriptyline both increase QTc interval. Avoid or Use Alternate Drug.hydroxyprogesterone caproate (DSC)Minor (1)hydroxyprogesterone caproate (DSC), nortriptyline. 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 nortriptyline both increase QTc interval. Use Caution/Monitor. hydroxyzine and nortriptyline both increase sedation. Use Caution/Monitor.hyoscyamineMonitor Closely (1)hyoscyamine and nortriptyline both decrease cholinergic effects/transmission. Use Caution/Monitor.hyoscyamine sprayMonitor Closely (1)hyoscyamine spray and nortriptyline both decrease cholinergic effects/transmission. Use Caution/Monitor.ibutilideContraindicated (1)nortriptyline and ibutilide both increase QTc interval. Contraindicated.iloperidoneMonitor Closely (2)nortriptyline and iloperidone both increase QTc interval. Modify Therapy/Monitor Closely. iloperidone and nortriptyline both increase sedation. Use Caution/Monitor.imatinibMonitor Closely (1)imatinib will increase the level or effect of nortriptyline by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.imipramineMonitor Closely (2)imipramine and nortriptyline both decrease cholinergic effects/transmission. Use Caution/Monitor. imipramine and nortriptyline both increase sedation. Use Caution/Monitor.Serious - Use Alternative (2)imipramine and nortriptyline both increase QTc interval. Avoid or Use Alternate Drug. imipramine and nortriptyline both increase serotonin levels. Avoid or Use Alternate Drug.indacaterol, inhaledMonitor Closely (1)indacaterol, inhaled, nortriptyline. 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)nortriptyline and indapamide both increase QTc interval. Contraindicated.insulin aspartMinor (1)nortriptyline increases effects of insulin aspart by pharmacodynamic synergism. Minor/Significance Unknown.insulin detemirMinor (1)nortriptyline increases effects of insulin detemir by pharmacodynamic synergism. Minor/Significance Unknown.insulin glargineMinor (1)nortriptyline increases effects of insulin glargine by pharmacodynamic synergism. Minor/Significance Unknown.insulin glulisineMinor (1)nortriptyline increases effects of insulin glulisine by pharmacodynamic synergism. Minor/Significance Unknown.insulin lisproMinor (1)nortriptyline increases effects of insulin lispro by pharmacodynamic synergism. Minor/Significance Unknown.insulin NPHMinor (1)nortriptyline increases effects of insulin NPH by pharmacodynamic synergism. Minor/Significance Unknown.insulin regular humanMinor (1)nortriptyline increases effects of insulin regular human by pharmacodynamic synergism. Minor/Significance Unknown.iobenguane I 123Contraindicated (1)nortriptyline 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)nortriptyline 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 nortriptyline 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 nortriptyline both increase serotonin levels. Contraindicated.isofluraneMonitor Closely (1)isoflurane and nortriptyline both increase QTc interval. Use Caution/Monitor.isoniazidMonitor Closely (1)nortriptyline and isoniazid both increase serotonin levels. Modify Therapy/Monitor Closely.isoproterenolMonitor Closely (1)nortriptyline increases and isoproterenol decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.Serious - Use Alternative (1)nortriptyline, 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, nortriptyline. Mechanism: unknown. Minor/Significance Unknown. Risk of cardiac arrhythmias.itraconazoleMonitor Closely (1)itraconazole and nortriptyline both increase QTc interval. Use Caution/Monitor.Serious - Use Alternative (1)nortriptyline and itraconazole both increase QTc interval. Avoid or Use Alternate Drug.ivosidenibSerious - Use Alternative (1)ivosidenib and nortriptyline both increase QTc interval. Avoid or Use Alternate Drug. Avoid coadministration of QTc prolonging drugs with ivosidenib or replace with alternate therapies. If coadministration of a QTc prolonging drug is unavoidable, monitor for increased risk of QTc interval prolongation.ketamineMonitor Closely (1)ketamine and nortriptyline both increase sedation. Use Caution/Monitor.Minor (1)ketamine, nortriptyline. Mechanism: unspecified interaction mechanism. Minor/Significance Unknown. Risk of arrhythmias or hypotension.ketoconazoleSerious - Use Alternative (1)nortriptyline and ketoconazole both increase QTc interval. Avoid or Use Alternate Drug.ketotifen, ophthalmicMonitor Closely (1)nortriptyline and ketotifen, ophthalmic both increase sedation. Use Caution/Monitor.L-tryptophanMonitor Closely (1)nortriptyline and L-tryptophan both increase serotonin levels. Modify Therapy/Monitor Closely.lapatinibMonitor Closely (1)nortriptyline and lapatinib both increase QTc interval. Modify Therapy/Monitor Closely.lasmiditanMonitor Closely (2)lasmiditan, nortriptyline. Either increases effects of the other by sedation. Use Caution/Monitor. Coadministration of lasmiditan and other CNS depressant drugs, including alcohol have not been evaluated in clinical studies. Lasmiditan may cause sedation, as well as other cognitive and/or neuropsychiatric adverse reactions. nortriptyline increases effects of lasmiditan by serotonin levels. Use Caution/Monitor. Coadministration may increase risk of serotonin syndrome.lefamulinSerious - Use Alternative (1)lefamulin and nortriptyline both increase QTc interval. Avoid or Use Alternate Drug.lemborexantMonitor Closely (1)lemborexant, nortriptyline. Either increases effects of the other by sedation. Modify Therapy/Monitor Closely. Dosage adjustment may be necessary if lemborexant is coadministered with other CNS depressants because of potentially additive effects.levalbuterolMonitor Closely (1)nortriptyline increases and levalbuterol decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.Serious - Use Alternative (1)nortriptyline, levalbuterol. 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.levofloxacinMonitor Closely (1)nortriptyline and levofloxacin both increase QTc interval. Modify Therapy/Monitor Closely.levoketoconazoleMonitor Closely (1)levoketoconazole will increase the level or effect of nortriptyline by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor.Serious - Use Alternative (1)nortriptyline and levoketoconazole both increase QTc interval. Avoid or Use Alternate Drug.levomilnacipranSerious - Use Alternative (1)levomilnacipran and nortriptyline both increase serotonin levels. Avoid or Use Alternate Drug.levorphanolMonitor Closely (1)levorphanol and nortriptyline both increase sedation. Use Caution/Monitor.levothyroxineMonitor Closely (1)levothyroxine increases effects of nortriptyline by Other (see comment). Use Caution/Monitor. Comment: Increased catecholamine receptor sensitivity; may increase CNS and cardiovascular effects, including arrhythmias.linezolidSerious - Use Alternative (1)linezolid and nortriptyline both increase serotonin levels. Avoid or Use Alternate Drug. Linezolid may increase serotonin as a result of MAO-A inhibition. If linezolid must be administered, discontinue serotonergic drug immediately and monitor for CNS toxicity. Serotonergic therapy may be resumed 24 hours after last linezolid dose or after 2 weeks of monitoring, whichever comes first.liothyronineMonitor Closely (1)liothyronine increases effects of nortriptyline by Other (see comment). Use Caution/Monitor. Comment: Increased catecholamine receptor sensitivity; may increase CNS and cardiovascular effects, including arrhythmias.liotrixMonitor Closely (1)liotrix increases effects of nortriptyline by Other (see comment). Use Caution/Monitor. Comment: Increased catecholamine receptor sensitivity; may increase CNS and cardiovascular effects, including arrhythmias.lisdexamfetamineMonitor Closely (2)nortriptyline, lisdexamfetamine. Either increases effects of the other by serotonin levels. Use Caution/Monitor. Initiate with lower doses and monitor for signs and symptoms of serotonin syndrome, particularly during initiation or dosage increase. If serotonin syndrome occurs, discontinue along with concomitant serotonergic drug(s). nortriptyline increases and lisdexamfetamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.Serious - Use Alternative (1)nortriptyline, lisdexamfetamine. 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.lithiumMonitor Closely (2)lithium and nortriptyline both increase QTc interval. Use Caution/Monitor. nortriptyline and lithium both increase serotonin levels. Modify Therapy/Monitor Closely.Minor (1)lithium, nortriptyline. Other (see comment). Minor/Significance Unknown. Comment: Risk of neurotoxicity in geriatric pts. Multiple mechanisms involved.lofepramineMonitor Closely (2)lofepramine and nortriptyline both decrease cholinergic effects/transmission. Use Caution/Monitor. lofepramine and nortriptyline both increase sedation. Use Caution/Monitor.Serious - Use Alternative (2)lofepramine and nortriptyline both increase QTc interval. Avoid or Use Alternate Drug. lofepramine and nortriptyline both increase serotonin levels. Avoid or Use Alternate Drug.lofexidineMonitor Closely (2)nortriptyline decreases effects of lofexidine by unspecified interaction mechanism. Use Caution/Monitor. nortriptyline and lofexidine both increase sedation. Use Caution/Monitor.loprazolamMonitor Closely (1)loprazolam and nortriptyline both increase sedation. Use Caution/Monitor.lorazepamMonitor Closely (1)lorazepam and nortriptyline both increase sedation. Use Caution/Monitor.lorcaserinMonitor Closely (1)lorcaserin will increase the level or effect of nortriptyline by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.Serious - Use Alternative (1)nortriptyline and lorcaserin both increase serotonin levels. Avoid or Use Alternate Drug.lormetazepamMonitor Closely (1)lormetazepam and nortriptyline both increase sedation. Use Caution/Monitor.loxapineMonitor Closely (1)loxapine and nortriptyline both increase sedation. Use Caution/Monitor.loxapine inhaledMonitor Closely (1)loxapine inhaled and nortriptyline both increase sedation. Use Caution/Monitor.lsdMonitor Closely (1)nortriptyline and lsd both increase serotonin levels. Modify Therapy/Monitor Closely.lumefantrineSerious - Use Alternative (2)nortriptyline and lumefantrine both increase QTc interval. Avoid or Use Alternate Drug. lumefantrine will increase the level or effect of nortriptyline by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.lurasidoneMonitor Closely (1)lurasidone increases effects of nortriptyline by Other (see comment). Use Caution/Monitor. Comment: Potential for additive CNS effects .macimorelinSerious - Use Alternative (1)macimorelin and nortriptyline both increase QTc interval. Avoid or Use Alternate Drug. Macimorelin causes an increase of ~11 msec in the corrected QT interval. Avoid coadministration with drugs that prolong QT interval, which could increase risk for developing torsade de pointes-type ventricular tachycardia. Allow sufficient washout time of drugs that are known to prolong the QT interval before administering macimorelin.maprotilineMonitor Closely (2)maprotiline and nortriptyline both decrease cholinergic effects/transmission. Use Caution/Monitor. maprotiline and nortriptyline both increase sedation. Use Caution/Monitor.Serious - Use Alternative (2)maprotiline and nortriptyline both increase QTc interval. Avoid or Use Alternate Drug. maprotiline and nortriptyline both increase serotonin levels. Avoid or Use Alternate Drug.maravirocMonitor Closely (1)maraviroc will increase the level or effect of nortriptyline by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.marijuanaMonitor Closely (2)marijuana will increase the level or effect of nortriptyline by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor. nortriptyline and marijuana both increase sedation. Use Caution/Monitor.meclizineMonitor Closely (1)meclizine and nortriptyline both decrease cholinergic effects/transmission. Use Caution/Monitor.mefloquineSerious - Use Alternative (1)mefloquine increases toxicity of nortriptyline by QTc interval. Avoid or Use Alternate Drug. Mefloquine may enhance the QTc prolonging effect of high risk QTc prolonging agents.melatoninMonitor Closely (1)nortriptyline and melatonin both increase sedation. Use Caution/Monitor.meperidineMonitor Closely (1)meperidine and nortriptyline both increase sedation. Use Caution/Monitor.Serious - Use Alternative (1)nortriptyline and meperidine both increase serotonin levels. Avoid or Use Alternate Drug.meprobamateMonitor Closely (1)nortriptyline and meprobamate both increase sedation. Use Caution/Monitor.mestranolMinor (1)mestranol, nortriptyline. Mechanism: unspecified interaction mechanism. Minor/Significance Unknown. Estrogens and progestins may decr tricyclic antidepressant effects, while increasing TCA plasma concentration and adverse effects.metaproterenolMonitor Closely (1)nortriptyline increases and metaproterenol decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.Serious - Use Alternative (1)nortriptyline, metaproterenol. 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.metaxaloneMonitor Closely (1)metaxalone and nortriptyline both increase sedation. Use Caution/Monitor.metforminMinor (1)nortriptyline increases effects of metformin by pharmacodynamic synergism. Minor/Significance Unknown.methadoneMonitor Closely (2)nortriptyline and methadone both increase QTc interval. Modify Therapy/Monitor Closely. methadone and nortriptyline both increase sedation. Use Caution/Monitor.methamphetamineMonitor Closely (1)nortriptyline increases and methamphetamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.Serious - Use Alternative (1)nortriptyline, methamphetamine. 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.methocarbamolMonitor Closely (1)methocarbamol and nortriptyline both increase sedation. Use Caution/Monitor.methscopolamineMonitor Closely (1)methscopolamine and nortriptyline both decrease cholinergic effects/transmission. Use Caution/Monitor.methylene blueSerious - Use Alternative (1)methylene blue and nortriptyline both increase serotonin levels. Avoid or Use Alternate Drug. Methylene blue may increase serotonin as a result of MAO-A inhibition. If methylene blue must be administered, discontinue serotonergic drug immediately and monitor for CNS toxicity. Serotonergic therapy may be resumed 24 hours after last methylene blue dose or after 2 weeks of monitoring, whichever comes first.methylenedioxymethamphetamineMonitor Closely (1)nortriptyline increases and methylenedioxymethamphetamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.Serious - Use Alternative (1)nortriptyline, methylenedioxymethamphetamine. 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.methylphenidateMonitor Closely (1)nortriptyline, methylphenidate. Other (see comment). Use Caution/Monitor. Comment: Tricyclic antidepressants increase or decrease effects of sympathomimetics, by blocking reuptake of NE, or blocking uptake of indirect sympathomimetics into the adrenergic neuron.methylphenidate transdermalMonitor Closely (1)methylphenidate transdermal will increase the level or effect of nortriptyline by decreasing elimination. Modify Therapy/Monitor Closely. Consider decreasing