AdultPediatricGeriatricDosage Forms & Strengths tablet 15mg Depression Initial 15 mg PO q8hr, increase not to exceed 20-30 mg q8hr Dosage should be increased to at least 60 mg/day at a fairly rapid pace consistent with patient tolerance; may be necessary to increase dosage up to 90 mg/day to obtain sufficient MAO inhibition; many patients do not show a clinical response until treatment at 60 mg has been continued for at least 4 weeks After maximum benefit from drug is achieved, decrease dose after maximum response (2-6 weeks) over 2-6 week period to maintain dose as low as 15 mg qDay or every other day Monitor blood pressure Dose considerations When discontinuing antidepressant therapy lasting for >3 weeks, gradually taper dose over 2-4wk to minimize withdrawal adverse effects Safety & efficacy not establishedDepression Initial 15 mg PO q8hr, increase not to exceed 20-30 mg q8hr Decrease dose after maximum response (2-6 weeks) over 2-6 week period to maintain dose as low as 15 mg qDay or every other day Monitor blood pressureInteraction CheckerEnter a drug name and phenelzineNo Results No Interactions Found Interactions FoundContraindicatedSerious - Use AlternativeSignificant - Monitor CloselyMinorAll Interactions Sort By: SeverityName Contraindicated (91)amitriptylinephenelzine and amitriptyline both increase serotonin levels. Contraindicated.amoxapinephenelzine and amoxapine both increase serotonin levels. Contraindicated.apraclonidineapraclonidine, phenelzine. Mechanism: unknown. Contraindicated. Contraindicated in mfr. prescribing info.phenelzine, apraclonidine. Mechanism: unknown. Contraindicated. Contraindicated in mfr prescribing info.armodafinilphenelzine increases effects of armodafinil by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.atomoxetinephenelzine increases effects of atomoxetine by pharmacodynamic synergism. Contraindicated. The use of atomoxetine with monoamine oxidase inhibitors (MAOIs) is contraindicated. Risk of acute hypertensive episode.benzphetaminephenelzine increases effects of benzphetamine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.brimonidinephenelzine, brimonidine. Mechanism: unknown. Contraindicated. Contraindicated in mfr prescribing info.bupropionphenelzine and bupropion both increase dopaminergic effects. Contraindicated. Bupropion inhibits reuptake of dopamine and norepinephrine (NE), and MAOIs decrease metabolism of dopamine and NE; coadministration increases risk for hypertensive reactions; allow at least 14 days between discontinuation of MAOI and initiating bupropionbuspironephenelzine and buspirone both increase serotonin levels. Contraindicated.phenelzine, buspirone. Mechanism: pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.caffeinephenelzine increases effects of caffeine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.carbamazepinecarbamazepine increases toxicity of phenelzine by unknown mechanism. Contraindicated. D/C MAO inhibitor 2 weeks before.citalopramphenelzine and citalopram both increase serotonin levels. Contraindicated. At least 2 weeks should elapse between discontinuation of MAOI therapy and the start of citalopram therapy, and at least 2 weeks between discontinuation of citalopram therapy and commencement of MAOI therapy.clomipraminephenelzine and clomipramine both increase serotonin levels. Contraindicated.cyclobenzaprinephenelzine and cyclobenzaprine both increase serotonin levels. Contraindicated. Do not coadminister cyclobenzaprine with MAOIs or within 14 days of discontinuing an MAOIcyproheptadinephenelzine, cyproheptadine. Other (see comment). Contraindicated. Comment: MAO inhibitors may prolong and intensify the anticholinergic effects of antihistamines. Cyproheptadine may diminish the serotonergic effect of MAO inhibitors.desipraminephenelzine and desipramine both increase serotonin levels. Contraindicated.desvenlafaxinephenelzine and desvenlafaxine both increase serotonin levels. Contraindicated. At least 14 days should elapse between discontinuation of MAOIs and initiation of treatment with a serotonergic drugdeutetrabenazinephenelzine, deutetrabenazine. Either increases levels of the other by sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Contraindicated. Deutetrabenazine should not be used in combination with an MAOI, or within 14 days of discontinuing therapy with an MAOI.dexfenfluraminephenelzine increases effects of dexfenfluramine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.dexmethylphenidatephenelzine increases effects of dexmethylphenidate by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.dextroamphetaminephenelzine increases effects of dextroamphetamine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.dextroamphetamine transdermalphenelzine increases effects of dextroamphetamine transdermal by decreasing metabolism. Contraindicated. MAOIs slows amphetamine metabolism, increasing amphetamine?s effect on norepinephrine release and other monoamines from adrenergic nerve endings causing signs of hypertensive crisis. Do not administer dextroamphetamine during or within 14 days following MAOI administration.dextromethorphanphenelzine and dextromethorphan both increase serotonin levels. Contraindicated.diethylpropionphenelzine increases effects of diethylpropion by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.dobutaminephenelzine increases effects of dobutamine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.dopaminephenelzine increases effects of dopamine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.dosulepinphenelzine and dosulepin both increase serotonin levels. Contraindicated.doxepinphenelzine and doxepin both increase serotonin levels. Contraindicated.duloxetinephenelzine and duloxetine both increase serotonin levels. Contraindicated.entacaponeentacapone, phenelzine. Either increases effects of the other by pharmacodynamic synergism. Contraindicated. Both nonselective MAO inhibitors and entacapone inhibit catecholamine metabolism, leading to increased levels of catecholamines. Potential for dangerously high HR or BP.ephedrinephenelzine increases effects of ephedrine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.epinephrinephenelzine increases effects of epinephrine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.epinephrine inhaledphenelzine and epinephrine inhaled both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Contraindicated. Coadministration of epinephrine inhaled with MAOIs or within 2 weeks after discontinuing an MAOI is contraindicated.escitalopramphenelzine and escitalopram both increase serotonin levels. Contraindicated.fenfluraminephenelzine increases effects of fenfluramine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.fenfluramine, phenelzine. Either increases effects of the other by serotonin levels. Contraindicated. Coadministration with drugs that increase serotonin may increase the risk of serotonin syndrome. Do not use concomitantly or within 14 days of MAOIs.fentanylphenelzine increases toxicity of fentanyl by Other (see comment). Contraindicated. Comment: Avoid fentanyl in patients who require concomitant administration MAOIs, or within 14 days of stopping an MAOI. Severe and unpredictable potentiation by MAO inhibitors has been reported with opioid analgesics.fentanyl intranasalphenelzine increases toxicity of fentanyl intranasal by Other (see comment). Contraindicated. Comment: Avoid fentanyl in patients who require concomitant administration MAOIs, or within 14 days of stopping an MAOI. Severe and unpredictable potentiation by MAO inhibitors has been reported with opioid analgesics.fentanyl transdermalphenelzine increases toxicity of fentanyl transdermal by Other (see comment). Contraindicated. Comment: Avoid fentanyl in patients who require concomitant administration MAOIs, or within 14 days of stopping an MAOI. Severe and unpredictable potentiation by MAO inhibitors has been reported with opioid analgesics.fentanyl transmucosalphenelzine increases toxicity of fentanyl transmucosal by Other (see comment). Contraindicated. Comment: Avoid fentanyl in patients who require concomitant administration MAOIs, or within 14 days of stopping an MAOI. Severe and unpredictable potentiation by MAO inhibitors has been reported with opioid analgesics.fluoxetinephenelzine and fluoxetine both increase serotonin levels. Contraindicated.imipraminephenelzine and imipramine both increase serotonin levels. Contraindicated.isocarboxazidisocarboxazid and phenelzine both increase serotonin levels. Contraindicated.isometheptenephenelzine, isometheptene. Either increases effects of the other by pharmacodynamic synergism. Contraindicated. Hypertension, V tach.isoproterenolphenelzine increases effects of isoproterenol by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.levodopaphenelzine, levodopa. Mechanism: pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.levodopa inhaledlevodopa inhaled increases effects of phenelzine by dopaminergic effects. Contraindicated. Levodopa may enhance risk for acute hypertensive episode if coadministered with nonselective MAOIs. Discontinue use of any nonselective MAO inhibitors at least 2 weeks before initiating levodopa inhaled.levomilnacipranphenelzine and levomilnacipran both increase serotonin levels. Contraindicated. Do not use MAOIs intended to treat psychiatric disorders with levomilnacipran or within 7 days of stopping levomilnacipran due to an increased risk of serotonin syndromelisdexamfetaminephenelzine, lisdexamfetamine. Either increases effects of the other by serotonin levels. Contraindicated. Do not use amphetamines during and within 14 days of discontinuation of monoamine oxidase inhibitors. .lofepraminephenelzine and lofepramine both increase serotonin levels. Contraindicated.maprotilinephenelzine and maprotiline both increase serotonin levels. Contraindicated.meperidinephenelzine and meperidine both increase serotonin levels. Contraindicated.phenelzine increases toxicity of meperidine by unknown mechanism. Contraindicated.methamphetaminephenelzine increases effects of methamphetamine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.methylenedioxymethamphetaminephenelzine increases effects of methylenedioxymethamphetamine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.methylphenidatephenelzine increases effects of methylphenidate by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode. Methylphenidate is contraindicated during treatment with an MAOI and also within a minimum of 14 days following discontinuation of an MAOI.methylphenidate transdermalmethylphenidate transdermal and phenelzine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Contraindicated. Coadministration of MAOIs and CNS stimulants can cause hypertensive crisis.midodrinephenelzine increases effects of midodrine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.milnacipranphenelzine and milnacipran both increase serotonin levels. Contraindicated.modafinilphenelzine increases effects of modafinil by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.nefazodonephenelzine and nefazodone both increase serotonin levels. Contraindicated.norepinephrinephenelzine increases effects of norepinephrine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.nortriptylinephenelzine and nortriptyline both increase serotonin levels. Contraindicated.opicaponeopicapone, phenelzine. Either increases effects of the other by pharmacodynamic synergism. Contraindicated. Both nonselective MAO inhibitors and opicapone inhibit catecholamine metabolism, leading to increased levels of catecholamines. Potential for dangerously high HR or BP.ozanimodphenelzine and ozanimod both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Contraindicated. Coadministration of ozanimod with MAO-B inhibitors may decrease exposure of the active metabolites of ozanimod, which may inhibit MAO. The potential for a clinical interaction with MAO inhibitors has not been studied; however, the increased risk of nonselective MAO inhibition may lead to a hypertensive crisis. Allow at least 14 days to elapse between discontinuing ozanimod and initiating with MAO inhibitors.paroxetinephenelzine and paroxetine both increase serotonin levels. Contraindicated.phendimetrazinephenelzine increases effects of phendimetrazine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.phenterminephenelzine increases effects of phentermine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.phenylephrinephenelzine increases effects of phenylephrine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.phenylephrine POphenelzine increases effects of phenylephrine PO by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.procarbazinephenelzine and procarbazine both increase serotonin levels. Contraindicated. At least 2 weeks should elapse between discontinuation of one MAOI and initiation of therapy with the other.propylhexedrinephenelzine increases effects of propylhexedrine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.protriptylinephenelzine and protriptyline both increase serotonin levels. Contraindicated.pseudoephedrinephenelzine increases effects of pseudoephedrine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.rasagilinerasagiline and phenelzine both increase serotonin levels. Contraindicated. Increased risk of hypertensive crisis. At least 14 days should elapse between discontinuation of rasagiline and initiation of another MAOI or discontinuation of another MAOI and initiation of rasagiline.safinamidephenelzine, safinamide. Either increases toxicity of the other by serotonin levels. Contraindicated. Coadministration increases risk of nonselective MAO inhibition, that may lead to hypertensive crisis. At least 14 days should elapse between discontinuating safinamide and initiating MAOIs.selegilineselegiline and phenelzine both increase serotonin levels. Contraindicated. At least 14 days should elapse between discontinuation of selegiline and initiation of another MAOI.selegiline transdermalselegiline transdermal and phenelzine both increase serotonin levels. Contraindicated.serdexmethylphenidate/dexmethylphenidatephenelzine increases effects of serdexmethylphenidate/dexmethylphenidate by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.sertralinephenelzine and sertraline both increase serotonin levels. Contraindicated.solriamfetolphenelzine will increase the level or effect of solriamfetol by sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Contraindicated. Do no use solriamfetol during and/or within 14 days of discontinuing MAOI treatment. MAOIs irreversibly inhibit the enzyme monamine oxidase, an enzyme involved in the degradation of various monoamines, including dopamine and norepinephrine. Solriamfetol increases synaptic dopamine and norepinephrine.St John's Wortphenelzine and St John's Wort both increase serotonin levels. Contraindicated.tetrabenazinetetrabenazine, phenelzine. Other (see comment). Contraindicated. Comment: Risk of acute hypertensive episode; separate by 14 d. Mechanism: MAOI causes accumulation of NE in neuron and tetrabenazine stimulates NE release.tolcaponetolcapone, phenelzine. Either increases effects of the other by pharmacodynamic synergism. Contraindicated. Both nonselective MAO inhibitors and tolcapone inhibit catecholamine metabolism, leading to increased levels of catecholamines. Potential for dangerously high HR or BP.tranylcyprominephenelzine and tranylcypromine both increase serotonin levels. Contraindicated.trazodonephenelzine and trazodone both increase serotonin levels. Contraindicated.trimipraminephenelzine and trimipramine both increase serotonin levels. Contraindicated.tyraminephenelzine increases effects of tyramine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode. Tyramine containing foods include cheese, red wine, caviar, herring, canned figs, fermented meats, fava beans, yeast extracts, miso, avocado.venlafaxinephenelzine and venlafaxine both increase serotonin levels. Contraindicated.vilazodonephenelzine, vilazodone. Either increases toxicity of the other by serotonin levels. Contraindicated. Coadministration with MAO-A inhibitors are contraindicated. Do not prescribe vilazodone within 14 days of discontinuing or starting an MAO inhibitor.vortioxetinephenelzine increases toxicity of vortioxetine by serotonin levels. Contraindicated.xylometazolinephenelzine increases effects of xylometazoline by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.yohimbinephenelzine increases effects of yohimbine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.Serious - Use Alternative (81)5-HTPphenelzine and 5-HTP both increase serotonin levels. Avoid or Use Alternate Drug.albuterolphenelzine increases effects of albuterol by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.alfentanilphenelzine increases toxicity of alfentanil by unknown mechanism. Avoid or Use Alternate Drug. Risk of hypotension, hyperpyrexia, somnolence, or death; separate by 14 d.almotriptanalmotriptan and phenelzine both increase serotonin levels. Avoid or Use Alternate Drug.phenelzine increases levels of almotriptan by decreasing metabolism. Contraindicated.arformoterolphenelzine increases effects of arformoterol by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.belladonna and opiumphenelzine increases toxicity of belladonna and opium by unknown mechanism. Avoid or Use Alternate Drug. Risk of hypotension, hyperpyrexia, somnolence, or death; separate by 14 d.benzhydrocodone/acetaminophenphenelzine increases toxicity