the dose of these drugs when given coadministered with methylphenidate. Monitor for drug toxiticities when initiating or discontinuing methylphenidate. metoclopramide intranasalSerious - Use Alternative (1)nortriptyline, metoclopramide intranasal. Either increases effects of the other by Other (see comment). Avoid or Use Alternate Drug. Comment: Avoid use of metoclopramide intranasal or interacting drug, depending on importance of drug to patient.midazolamMonitor Closely (1)midazolam and nortriptyline both increase sedation. Use Caution/Monitor.midazolam intranasalMonitor Closely (1)midazolam intranasal, nortriptyline. Either increases toxicity of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Concomitant use of barbiturates, alcohol, or other CNS depressants may increase the risk of hypoventilation, airway obstruction, desaturation, or apnea and may contribute to profound and/or prolonged drug effect.midodrineMonitor Closely (1)nortriptyline increases and midodrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.Serious - Use Alternative (1)nortriptyline, midodrine. 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.mifepristoneMonitor Closely (1)mifepristone, nortriptyline. QTc interval. Modify Therapy/Monitor Closely. Use alternatives if available.miglitolMinor (1)nortriptyline increases effects of miglitol by pharmacodynamic synergism. Minor/Significance Unknown.milnacipranSerious - Use Alternative (1)milnacipran and nortriptyline both increase serotonin levels. Avoid or Use Alternate Drug.mirabegronMonitor Closely (1)mirabegron will increase the level or effect of nortriptyline by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.mirtazapineMonitor 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.mobocertinibSerious - Use Alternative (1)mobocertinib and nortriptyline both increase QTc interval. Avoid or Use Alternate Drug. If coadministration unavoidable, reduce mobocertinib dose and monitor QTc interval more frequently.modafinilMonitor Closely (1)nortriptyline increases and modafinil decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.morphineMonitor Closely (2)nortriptyline and morphine both increase serotonin levels. Modify Therapy/Monitor Closely. morphine and nortriptyline both increase sedation. Use Caution/Monitor.motherwortMonitor Closely (1)nortriptyline and motherwort both increase sedation. Use Caution/Monitor.moxifloxacinSerious - Use Alternative (1)nortriptyline and moxifloxacin both increase QTc interval. Avoid or Use Alternate Drug.moxonidineMonitor Closely (1)nortriptyline and moxonidine both increase sedation. Use Caution/Monitor.nabiloneMonitor Closely (1)nortriptyline and nabilone both increase sedation. Use Caution/Monitor.nalbuphineMonitor Closely (1)nalbuphine and nortriptyline both increase sedation. Use Caution/Monitor.naratriptanMonitor Closely (1)naratriptan and nortriptyline both increase serotonin levels. Modify Therapy/Monitor Closely.nateglinideMinor (1)nortriptyline increases effects of nateglinide by pharmacodynamic synergism. Minor/Significance Unknown.nefazodoneSerious - Use Alternative (1)nefazodone and nortriptyline both increase serotonin levels. Avoid or Use Alternate Drug.nefopamMonitor Closely (1)nefopam, nortriptyline. Mechanism: unspecified interaction mechanism. Use Caution/Monitor. Use combination with caution.neostigmineMonitor Closely (1)neostigmine increases and nortriptyline decreases cholinergic effects/transmission. Effect of interaction is not clear, use caution. Use Caution/Monitor.netupitant/palonosetronSerious - Use Alternative (1)netupitant/palonosetron, nortriptyline. Either increases toxicity of the other by serotonin levels. Avoid or Use Alternate Drug.nilotinibMonitor Closely (1)nilotinib will increase the level or effect of nortriptyline by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.Serious - Use Alternative (1)nortriptyline and nilotinib both increase QTc interval. Avoid or Use Alternate Drug.norepinephrineMonitor Closely (2)nortriptyline increases effects of norepinephrine by unknown mechanism. Use Caution/Monitor. nortriptyline increases and norepinephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.Serious - Use Alternative (1)nortriptyline, norepinephrine. 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.octreotideSerious - Use Alternative (1)nortriptyline and octreotide both increase QTc interval. Avoid or Use Alternate Drug.octreotide (Antidote)Serious - Use Alternative (1)nortriptyline and octreotide (Antidote) both increase QTc interval. Avoid or Use Alternate Drug.ofloxacinMonitor Closely (1)nortriptyline and ofloxacin both increase QTc interval. Modify Therapy/Monitor Closely.olanzapineMonitor Closely (2)olanzapine and nortriptyline both increase QTc interval. Use Caution/Monitor. olanzapine and nortriptyline both increase sedation. Use Caution/Monitor.oliceridineMonitor Closely (2)nortriptyline, oliceridine. Either increases effects of the other by serotonin levels. Modify Therapy/Monitor Closely. nortriptyline increases toxicity of oliceridine by Other (see comment). Modify Therapy/Monitor Closely. Comment: Anticholinergic drugs may increase risk of urinary retention and/or severe constipation, which may lead to paralytic ileus. Monitor for signs of urinary retention or reduced gastric motility if oliceridine is coadministered with anticholinergics.olodaterol inhaledMonitor Closely (1)nortriptyline and olodaterol inhaled both increase QTc interval. Use Caution/Monitor. TCAs prolong the QTc interval and may potentiate the effects of beta2 agonists on the cardiovascular system; increased risk of ventricular arrhythmiasolopatadine intranasalSerious - Use Alternative (1)nortriptyline 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. onabotulinumtoxinAMonitor Closely (1)onabotulinumtoxinA and nortriptyline both decrease cholinergic effects/transmission. Use Caution/Monitor.ondansetronSerious - Use Alternative (2)nortriptyline and ondansetron both increase QTc interval. Avoid or Use Alternate Drug. Avoid with congenital long QT syndrome; ECG monitoring recommended with concomitant medications that prolong QT interval, electrolyte abnormalities, CHF, or bradyarrhythmias. ondansetron, nortriptyline. Either increases toxicity of the other by serotonin levels. Avoid or Use Alternate Drug.opium tinctureMonitor Closely (1)opium tincture and nortriptyline both increase sedation. Use Caution/Monitor.orphenadrineMonitor Closely (2)nortriptyline and orphenadrine both decrease cholinergic effects/transmission. Use Caution/Monitor. orphenadrine and nortriptyline both increase sedation. Use Caution/Monitor.osilodrostatMonitor Closely (1)osilodrostat and nortriptyline both increase QTc interval. Use Caution/Monitor.osimertinibMonitor Closely (1)osimertinib and nortriptyline both increase QTc interval. Use Caution/Monitor. Conduct periodic monitoring with ECGs and electrolytes in patients taking drugs known to prolong the QTc interval.oxazepamMonitor Closely (1)oxazepam and nortriptyline both increase sedation. Use Caution/Monitor.oxybutyninMonitor Closely (1)oxybutynin and nortriptyline both decrease cholinergic effects/transmission. Use Caution/Monitor.oxybutynin topicalMonitor Closely (1)oxybutynin topical and nortriptyline both decrease cholinergic effects/transmission. Use Caution/Monitor.oxybutynin transdermalMonitor Closely (1)oxybutynin transdermal and nortriptyline both decrease cholinergic effects/transmission. Use Caution/Monitor.oxycodoneMonitor Closely (1)oxycodone and nortriptyline both increase sedation. Use Caution/Monitor.oxymetazoline intranasalMonitor Closely (1)nortriptyline increases effects of oxymetazoline intranasal by pharmacodynamic synergism. Use Caution/Monitor. TCAs inhibit norepinephrine uptake in adrenergic neurons, thereby increasing synaptic norepinephrine levels. Coadministration with alpha1 agonists may cause increased adrenergic receptor stimulation. When oxymetazoline is combined with intranasal tetracaine for dental anesthesia, avoid or use alternant anesthetic in patients taking TCAs.oxymorphoneMonitor Closely (1)oxymorphone and nortriptyline both increase sedation. Use Caution/Monitor.ozanimodMonitor Closely (1)ozanimod and nortriptyline both increase QTc interval. Modify Therapy/Monitor Closely. The potential additive effects on heart rate, treatment with ozanimod should generally not be initiated in patients who are concurrently treated with QT prolonging drugs with known arrhythmogenic properties.Serious - Use Alternative (1)ozanimod increases toxicity of nortriptyline by sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Avoid or Use Alternate Drug. Because the active metabolite of ozanimod inhibits MAO-B in vitro, there is a potential for serious adverse reactions, including hypertensive crisis. Therefore, coadministration of ozanimod with drugs that can increase norepinephrine or serotonin is not recommended. Monitor for hypertension with concomitant use.paliperidoneMonitor Closely (2)nortriptyline and paliperidone both increase QTc interval. Modify Therapy/Monitor Closely. paliperidone and nortriptyline both increase sedation. Use Caution/Monitor.palonosetronSerious - Use Alternative (1)palonosetron, nortriptyline. Either increases toxicity of the other by serotonin levels. Avoid or Use Alternate Drug.panax ginsengMinor (1)panax ginseng increases effects of nortriptyline by pharmacodynamic synergism. Minor/Significance Unknown.pancuroniumMonitor Closely (1)pancuronium and nortriptyline both decrease cholinergic effects/transmission. Use Caution/Monitor.papaveretumMonitor Closely (1)papaveretum and nortriptyline both increase sedation. Use Caution/Monitor.papaverineMonitor Closely (1)nortriptyline and papaverine both increase sedation. Use Caution/Monitor.parecoxibMonitor Closely (1)parecoxib will increase the level or effect of nortriptyline by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.paroxetineMonitor Closely (1)nortriptyline and paroxetine both increase QTc interval. Modify Therapy/Monitor Closely.Serious - Use Alternative (2)paroxetine and nortriptyline both increase serotonin levels. Avoid or Use Alternate Drug. paroxetine will increase the level or effect of nortriptyline by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.pasireotideMonitor Closely (1)nortriptyline and pasireotide both increase QTc interval. Modify Therapy/Monitor Closely.pazopanibMonitor Closely (1)nortriptyline and pazopanib both increase QTc interval. Use Caution/Monitor.peginterferon alfa 2bMonitor Closely (1)peginterferon alfa 2b, nortriptyline. 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.pentamidineContraindicated (1)nortriptyline and pentamidine both increase QTc interval. Contraindicated.pentazocineMonitor Closely (2)nortriptyline and pentazocine both increase serotonin levels. Modify Therapy/Monitor Closely. pentazocine and nortriptyline both increase sedation. Use Caution/Monitor.pentobarbitalMonitor Closely (1)pentobarbital and nortriptyline both increase sedation. Use Caution/Monitor.Minor (1)pentobarbital, nortriptyline. Other (see comment). Minor/Significance Unknown. Comment: Barbiturates may increase adverse effects, including respiratory depression, produced by toxic doses of TCAs. With therapeutic doses of TCAs, barbiturates increase metabolism and decrease blood concentrations of TCAs.perphenazineMonitor Closely (2)perphenazine will increase the level or effect of nortriptyline by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor. perphenazine and nortriptyline both increase sedation. Use Caution/Monitor.Serious - Use Alternative (1)perphenazine and nortriptyline both increase QTc interval. Avoid or Use Alternate Drug.Minor (2)nortriptyline, perphenazine. Either increases levels of the other by decreasing metabolism. Minor/Significance Unknown. Additive anticholinergic effects. nortriptyline, perphenazine. Either increases levels of the other by pharmacodynamic synergism. Minor/Significance Unknown. Additive anticholinergic effects.phendimetrazineMonitor Closely (1)nortriptyline increases and phendimetrazine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.Serious - Use Alternative (1)nortriptyline, phendimetrazine. 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.phenelzineContraindicated (1)phenelzine and nortriptyline both increase serotonin levels. Contraindicated.phenobarbitalMonitor Closely (1)phenobarbital and nortriptyline both increase sedation. Use Caution/Monitor.Minor (1)phenobarbital, nortriptyline. Other (see comment). Minor/Significance Unknown. Comment: Barbiturates may increase adverse effects, including respiratory depression, produced by toxic doses of TCAs. With therapeutic doses of TCAs, barbiturates increase metabolism and decrease blood concentrations of TCAs.phentermineMonitor Closely (1)nortriptyline increases and phentermine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.Serious - Use Alternative (1)nortriptyline, phentermine. 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.phenylephrineMonitor Closely (1)nortriptyline increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.Serious - Use Alternative (1)nortriptyline, phenylephrine. 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.phenylephrine ophthalmicMonitor Closely (1)nortriptyline, phenylephrine ophthalmic. 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.phenylephrine POMonitor Closely (1)nortriptyline increases and phenylephrine PO decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. .Serious - Use Alternative (1)nortriptyline, phenylephrine PO. 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.pholcodineMonitor Closely (1)nortriptyline and pholcodine both increase sedation. Use Caution/Monitor.physostigmineMonitor Closely (1)physostigmine increases and nortriptyline decreases cholinergic effects/transmission. Effect of interaction is not clear, use caution. Use Caution/Monitor.pilocarpineMonitor Closely (1)pilocarpine increases and nortriptyline decreases cholinergic effects/transmission. Effect of interaction is not clear, use caution. Use Caution/Monitor.pimozideContraindicated (1)nortriptyline and pimozide both increase QTc interval. Contraindicated.Monitor Closely (1)pimozide and nortriptyline both increase sedation. Use Caution/Monitor.pioglitazoneMinor (1)nortriptyline increases effects of pioglitazone by pharmacodynamic synergism. Minor/Significance Unknown.pirbuterolMonitor Closely (1)nortriptyline increases and pirbuterol decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.Serious - Use Alternative (1)nortriptyline, pirbuterol. 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.pitolisantSerious - Use Alternative (1)nortriptyline 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.pleurisy rootMinor (1)pleurisy root decreases effects of nortriptyline by unspecified interaction mechanism. Minor/Significance Unknown. Theoretical interaction.posaconazoleMonitor Closely (1)nortriptyline and posaconazole both increase QTc interval. Modify Therapy/Monitor Closely.pralidoximeMonitor Closely (1)pralidoxime and nortriptyline both decrease cholinergic effects/transmission. Use Caution/Monitor.pregabalinMonitor Closely (1)pregabalin, nortriptyline. 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.primidoneMonitor Closely (1)primidone and nortriptyline both increase sedation. Use Caution/Monitor.Minor (1)primidone, nortriptyline. Other (see comment). Minor/Significance Unknown. Comment: Barbiturates may increase adverse effects, including respiratory depression, produced by toxic doses of TCAs. With therapeutic doses of TCAs, barbiturates increase metabolism and decrease blood concentrations of TCAs.procainamideContraindicated (1)nortriptyline and procainamide both increase QTc interval. Contraindicated.procarbazineContraindicated (1)procarbazine and nortriptyline both