Dosing & Uses
Dosage 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 established
Depression
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 pressure
Interactions
Interaction Checker
No Results
Contraindicated
Serious - Use Alternative
Significant - Monitor Closely
Minor
Contraindicated (91)
- amitriptyline
phenelzine and amitriptyline both increase serotonin levels. Contraindicated.
- amoxapine
phenelzine and amoxapine both increase serotonin levels. Contraindicated.
- apraclonidine
apraclonidine, phenelzine. Mechanism: unknown. Contraindicated. Contraindicated in mfr. prescribing info.
phenelzine, apraclonidine. Mechanism: unknown. Contraindicated. Contraindicated in mfr prescribing info. - armodafinil
phenelzine increases effects of armodafinil by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.
- atomoxetine
phenelzine increases effects of atomoxetine by pharmacodynamic synergism. Contraindicated. The use of atomoxetine with monoamine oxidase inhibitors (MAOIs) is contraindicated. Risk of acute hypertensive episode.
- benzphetamine
phenelzine increases effects of benzphetamine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.
- brimonidine
phenelzine, brimonidine. Mechanism: unknown. Contraindicated. Contraindicated in mfr prescribing info.
- bupropion
phenelzine 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 bupropion
- buspirone
phenelzine and buspirone both increase serotonin levels. Contraindicated.
phenelzine, buspirone. Mechanism: pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode. - caffeine
phenelzine increases effects of caffeine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.
- carbamazepine
carbamazepine increases toxicity of phenelzine by unknown mechanism. Contraindicated. D/C MAO inhibitor 2 weeks before.
- citalopram
phenelzine 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.
- clomipramine
phenelzine and clomipramine both increase serotonin levels. Contraindicated.
- cyclobenzaprine
phenelzine and cyclobenzaprine both increase serotonin levels. Contraindicated. Do not coadminister cyclobenzaprine with MAOIs or within 14 days of discontinuing an MAOI
- cyproheptadine
phenelzine, 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.
- desipramine
phenelzine and desipramine both increase serotonin levels. Contraindicated.
- desvenlafaxine
phenelzine and desvenlafaxine both increase serotonin levels. Contraindicated. At least 14 days should elapse between discontinuation of MAOIs and initiation of treatment with a serotonergic drug
- deutetrabenazine
phenelzine, 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.
- dexfenfluramine
phenelzine increases effects of dexfenfluramine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.
- dexmethylphenidate
phenelzine increases effects of dexmethylphenidate by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.
- dextroamphetamine
phenelzine increases effects of dextroamphetamine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.
- dextroamphetamine transdermal
phenelzine 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.
- dextromethorphan
phenelzine and dextromethorphan both increase serotonin levels. Contraindicated.
- diethylpropion
phenelzine increases effects of diethylpropion by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.
- dobutamine
phenelzine increases effects of dobutamine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.
- dopamine
phenelzine increases effects of dopamine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.
- dosulepin
phenelzine and dosulepin both increase serotonin levels. Contraindicated.
- doxepin
phenelzine and doxepin both increase serotonin levels. Contraindicated.
- duloxetine
phenelzine and duloxetine both increase serotonin levels. Contraindicated.
- entacapone
entacapone, 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.
- ephedrine
phenelzine increases effects of ephedrine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.
- epinephrine
phenelzine increases effects of epinephrine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.
- epinephrine inhaled
phenelzine 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.
- escitalopram
phenelzine and escitalopram both increase serotonin levels. Contraindicated.
- fenfluramine
phenelzine 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. - fentanyl
phenelzine 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 intranasal
phenelzine 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 transdermal
phenelzine 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 transmucosal
phenelzine 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.
- fluoxetine
phenelzine and fluoxetine both increase serotonin levels. Contraindicated.
- imipramine
phenelzine and imipramine both increase serotonin levels. Contraindicated.
- isocarboxazid
isocarboxazid and phenelzine both increase serotonin levels. Contraindicated.
- isometheptene
phenelzine, isometheptene. Either increases effects of the other by pharmacodynamic synergism. Contraindicated. Hypertension, V tach.
- isoproterenol
phenelzine increases effects of isoproterenol by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.
- levodopa
phenelzine, levodopa. Mechanism: pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.
- levodopa inhaled
levodopa 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.
- levomilnacipran
phenelzine 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 syndrome
- lisdexamfetamine
phenelzine, 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. .
- lofepramine
phenelzine and lofepramine both increase serotonin levels. Contraindicated.
- maprotiline
phenelzine and maprotiline both increase serotonin levels. Contraindicated.
- meperidine
phenelzine and meperidine both increase serotonin levels. Contraindicated.
phenelzine increases toxicity of meperidine by unknown mechanism. Contraindicated. - methamphetamine
phenelzine increases effects of methamphetamine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.
- methylenedioxymethamphetamine
phenelzine increases effects of methylenedioxymethamphetamine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.
- methylphenidate
phenelzine 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 transdermal
methylphenidate 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.
- midodrine
phenelzine increases effects of midodrine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.
- milnacipran
phenelzine and milnacipran both increase serotonin levels. Contraindicated.
- modafinil
phenelzine increases effects of modafinil by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.
- nefazodone
phenelzine and nefazodone both increase serotonin levels. Contraindicated.
- norepinephrine
phenelzine increases effects of norepinephrine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.
- nortriptyline
phenelzine and nortriptyline both increase serotonin levels. Contraindicated.
- opicapone
opicapone, 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.
- ozanimod
phenelzine 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.
- paroxetine
phenelzine and paroxetine both increase serotonin levels. Contraindicated.
- phendimetrazine
phenelzine increases effects of phendimetrazine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.
- phentermine
phenelzine increases effects of phentermine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.
- phenylephrine
phenelzine increases effects of phenylephrine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.
- phenylephrine PO
phenelzine increases effects of phenylephrine PO by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.
- procarbazine
phenelzine 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.
- propylhexedrine
phenelzine increases effects of propylhexedrine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.
- protriptyline
phenelzine and protriptyline both increase serotonin levels. Contraindicated.
- pseudoephedrine
phenelzine increases effects of pseudoephedrine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.
- rasagiline
rasagiline 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.
- safinamide
phenelzine, 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.
- selegiline
selegiline and phenelzine both increase serotonin levels. Contraindicated. At least 14 days should elapse between discontinuation of selegiline and initiation of another MAOI.
- selegiline transdermal
selegiline transdermal and phenelzine both increase serotonin levels. Contraindicated.
- serdexmethylphenidate/dexmethylphenidate
phenelzine increases effects of serdexmethylphenidate/dexmethylphenidate by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.
- sertraline
phenelzine and sertraline both increase serotonin levels. Contraindicated.
- solriamfetol
phenelzine 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 Wort
phenelzine and St John's Wort both increase serotonin levels. Contraindicated.
- tetrabenazine
tetrabenazine, 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.
- tolcapone
tolcapone, 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.
- tranylcypromine
phenelzine and tranylcypromine both increase serotonin levels. Contraindicated.
- trazodone
phenelzine and trazodone both increase serotonin levels. Contraindicated.
- trimipramine
phenelzine and trimipramine both increase serotonin levels. Contraindicated.
- tyramine
phenelzine 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.
- venlafaxine
phenelzine and venlafaxine both increase serotonin levels. Contraindicated.
- vilazodone
phenelzine, 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.
- vortioxetine
phenelzine increases toxicity of vortioxetine by serotonin levels. Contraindicated.
- xylometazoline
phenelzine increases effects of xylometazoline by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.
- yohimbine
phenelzine increases effects of yohimbine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.
Serious - Use Alternative (81)
- 5-HTP
phenelzine and 5-HTP both increase serotonin levels. Avoid or Use Alternate Drug.
- albuterol
phenelzine increases effects of albuterol by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.
- alfentanil
phenelzine increases toxicity of alfentanil by unknown mechanism. Avoid or Use Alternate Drug. Risk of hypotension, hyperpyrexia, somnolence, or death; separate by 14 d.
- almotriptan
almotriptan and phenelzine both increase serotonin levels. Avoid or Use Alternate Drug.
phenelzine increases levels of almotriptan by decreasing metabolism. Contraindicated. - arformoterol
phenelzine increases effects of arformoterol by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.
- belladonna and opium
phenelzine 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/acetaminophen
phenelzine increases toxicity of benzhydrocodone/acetaminophen by serotonin levels. Avoid or Use Alternate Drug. MAOI interactions with opioids may manifest as serotonin syndrome or opioid toxicity (eg, respiratory depression, coma). Opioids are not recommended for patients taking MAOIs or within 14 days of stopping MAOIs. If urgent opioid treatment needed, use test doses and frequent titration of small doses to treat pain while closely monitoring blood pressure and signs and symptoms of CNS and respiratory depression.
- buprenorphine
phenelzine increases toxicity of buprenorphine by unknown mechanism. Avoid or Use Alternate Drug. Risk of hypotension, hyperpyrexia, somnolence, or death; separate by 14 d.
- buprenorphine buccal
phenelzine increases toxicity of buprenorphine buccal by unknown mechanism. Avoid or Use Alternate Drug. Risk of hypotension, hyperpyrexia, somnolence, or death; separate by 14 d.
- butorphanol
phenelzine increases toxicity of butorphanol by unknown mechanism. Avoid or Use Alternate Drug. Risk of hypotension, hyperpyrexia, somnolence, or death; separate by 14 d.
- cocaine topical
phenelzine and cocaine topical both increase serotonin levels. Contraindicated.
- codeine
phenelzine increases toxicity of codeine by unknown mechanism. Avoid or Use Alternate Drug. Risk of hypotension, hyperpyrexia, somnolence, or death; separate by 14 d.
- desflurane
phenelzine increases levels of desflurane by pharmacodynamic synergism. Avoid or Use Alternate Drug.
- dexfenfluramine
phenelzine and dexfenfluramine both increase serotonin levels. Avoid or Use Alternate Drug.
- dextroamphetamine
phenelzine and dextroamphetamine both increase serotonin levels. Avoid or Use Alternate Drug.
- dextromoramide
phenelzine increases toxicity of dextromoramide by unknown mechanism. Avoid or Use Alternate Drug. Risk of hypotension, hyperpyrexia, somnolence, or death; separate by 14 d.
- diamorphine
phenelzine increases toxicity of diamorphine by unknown mechanism. Avoid or Use Alternate Drug. Risk of hypotension, hyperpyrexia, somnolence, or death; separate by 14 d.
- difenoxin hcl
phenelzine increases toxicity of difenoxin hcl by unknown mechanism. Avoid or Use Alternate Drug. Risk of hypotension, hyperpyrexia, somnolence, or death; separate by 14 d.
- dihydroergotamine
phenelzine and dihydroergotamine both increase serotonin levels. Avoid or Use Alternate Drug.
- dihydroergotamine intranasal
phenelzine and dihydroergotamine intranasal both increase serotonin levels. Avoid or Use Alternate Drug.
- diphenoxylate hcl
phenelzine increases toxicity of diphenoxylate hcl by unknown mechanism. Avoid or Use Alternate Drug. Risk of hypotension, hyperpyrexia, somnolence, or death; separate by 14 d.
- dipipanone
phenelzine increases toxicity of dipipanone by unknown mechanism. Avoid or Use Alternate Drug. Risk of hypotension, hyperpyrexia, somnolence, or death; separate by 14 d.
- dolasetron
dolasetron, phenelzine. Either increases toxicity of the other by serotonin levels. Avoid or Use Alternate Drug.
- dopexamine
phenelzine increases effects of dopexamine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.
- doxapram
doxapram increases effects of phenelzine by pharmacodynamic synergism. Avoid or Use Alternate Drug. Additive pressor effect.
- doxepin cream
phenelzine increases levels of doxepin cream by pharmacodynamic synergism. Contraindicated. D/C MAO inhibitor 2 weeks before.
- eletriptan
eletriptan and phenelzine both increase serotonin levels. Avoid or Use Alternate Drug.
phenelzine increases levels of eletriptan by decreasing metabolism. Contraindicated. - epinephrine racemic
phenelzine increases effects of epinephrine racemic by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.
- ergotamine
phenelzine and ergotamine both increase serotonin levels. Avoid or Use Alternate Drug.
- fenfluramine
phenelzine and fenfluramine both increase serotonin levels. Avoid or Use Alternate Drug.
- fluvoxamine
fluvoxamine and phenelzine both increase serotonin levels. Contraindicated.
- formoterol
phenelzine increases effects of formoterol by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.
- frovatriptan
frovatriptan and phenelzine both increase serotonin levels. Avoid or Use Alternate Drug.
phenelzine increases levels of frovatriptan by decreasing metabolism. Contraindicated. - granisetron
granisetron, phenelzine. Either increases toxicity of the other by serotonin levels. Avoid or Use Alternate Drug.
- hydrocodone
phenelzine increases toxicity of hydrocodone by serotonin levels. Avoid or Use Alternate Drug. MAOI interactions with opioids may manifest as serotonin syndrome or opioid toxicity (eg, respiratory depression, coma). Opioids are not recommended for patients taking MAOIs or within 14 days of stopping MAOIs. If urgent opioid treatment needed, use test doses and frequent titration of small doses to treat pain while closely monitoring blood pressure and signs and symptoms of CNS and respiratory depression.
- hydromorphone
phenelzine increases toxicity of hydromorphone by unknown mechanism. Avoid or Use Alternate Drug. Risk of hypotension, hyperpyrexia, somnolence, or death; separate by 14 d.
- iobenguane I 131
phenelzine 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.
- isoniazid
phenelzine and isoniazid both increase serotonin levels. Avoid or Use Alternate Drug.
- ketamine
phenelzine increases levels of ketamine by pharmacodynamic synergism. Avoid or Use Alternate Drug.
- L-tryptophan
phenelzine and L-tryptophan both increase serotonin levels. Avoid or Use Alternate Drug.
- levalbuterol
phenelzine increases effects of levalbuterol by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.
- levorphanol
phenelzine increases toxicity of levorphanol by unknown mechanism. Avoid or Use Alternate Drug. Risk of hypotension, hyperpyrexia, somnolence, or death; separate by 14 d.
- linezolid
linezolid and phenelzine 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.
- lithium
phenelzine and lithium both increase serotonin levels. Avoid or Use Alternate Drug.
- lorcaserin
phenelzine and lorcaserin both increase serotonin levels. Avoid or Use Alternate Drug.
- lsd
phenelzine and lsd both increase serotonin levels. Avoid or Use Alternate Drug.
- metaproterenol
phenelzine increases effects of metaproterenol by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.
- methadone
phenelzine increases toxicity of methadone by unknown mechanism. Avoid or Use Alternate Drug. Risk of hypotension, hyperpyrexia, somnolence, or death; separate by 14 d.
- methylene blue
methylene blue and phenelzine 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.
- metoclopramide intranasal
metoclopramide intranasal increases toxicity of phenelzine by Other (see comment). Avoid or Use Alternate Drug. Comment: Metoclopramide may enhance the hypertensive effect of monoamine oxidase inhibitors.
- mirtazapine
phenelzine and mirtazapine both increase serotonin levels. Avoid or Use Alternate Drug.
- morphine
phenelzine and morphine both increase serotonin levels. Avoid or Use Alternate Drug.
phenelzine increases toxicity of morphine by unknown mechanism. Avoid or Use Alternate Drug. Risk of hypotension, hyperpyrexia, somnolence, or death; separate by 14 d. - nalbuphine
phenelzine increases toxicity of nalbuphine by unknown mechanism. Avoid or Use Alternate Drug. Risk of hypotension, hyperpyrexia, somnolence, or death; separate by 14 d.
- naratriptan
naratriptan and phenelzine both increase serotonin levels. Avoid or Use Alternate Drug.
phenelzine increases levels of naratriptan by decreasing metabolism. Contraindicated. - netupitant/palonosetron
netupitant/palonosetron, phenelzine. Either increases toxicity of the other by serotonin levels. Avoid or Use Alternate Drug.
- ondansetron
ondansetron, phenelzine. Either increases toxicity of the other by serotonin levels. Avoid or Use Alternate Drug.
- opium tincture
phenelzine increases toxicity of opium tincture by unknown mechanism. Avoid or Use Alternate Drug. Risk of hypotension, hyperpyrexia, somnolence, or death; separate by 14 d.
- oxycodone
phenelzine increases toxicity of oxycodone by unknown mechanism. Avoid or Use Alternate Drug. Risk of hypotension, hyperpyrexia, somnolence, or death; separate by 14 d.
- oxymetazoline intranasal
phenelzine increases effects of oxymetazoline intranasal by pharmacodynamic synergism. Avoid or Use Alternate Drug. MAOIs cause norepinephrine accumulation within adrenergic neurons. Significant hypertension can result if coadministered with alpha1 agonists.
- oxymorphone
phenelzine increases toxicity of oxymorphone by unknown mechanism. Avoid or Use Alternate Drug. Risk of hypotension, hyperpyrexia, somnolence, or death; separate by 14 d.
- palonosetron
palonosetron, phenelzine. Either increases toxicity of the other by serotonin levels. Avoid or Use Alternate Drug.
- papaveretum
phenelzine increases toxicity of papaveretum by unknown mechanism. Avoid or Use Alternate Drug. Risk of hypotension, hyperpyrexia, somnolence, or death; separate by 14 d.
- pentazocine
phenelzine and pentazocine both increase serotonin levels. Avoid or Use Alternate Drug.
phenelzine increases toxicity of pentazocine by unknown mechanism. Avoid or Use Alternate Drug. Risk of hypotension, hyperpyrexia, somnolence, or death; separate by 14 d. - pirbuterol
phenelzine increases effects of pirbuterol by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.
- propofol
phenelzine increases levels of propofol by pharmacodynamic synergism. Avoid or Use Alternate Drug.
- rizatriptan
rizatriptan and phenelzine both increase serotonin levels. Avoid or Use Alternate Drug.
phenelzine increases levels of rizatriptan by decreasing metabolism. Contraindicated. - salmeterol
phenelzine increases effects of salmeterol by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.
- SAMe
phenelzine and SAMe both increase serotonin levels. Avoid or Use Alternate Drug.
- sevoflurane
phenelzine increases levels of sevoflurane by pharmacodynamic synergism. Avoid or Use Alternate Drug.
- sufentanil
phenelzine increases toxicity of sufentanil by unknown mechanism. Avoid or Use Alternate Drug. Risk of hypotension, hyperpyrexia, somnolence, or death; separate by 14 d.
- sufentanil SL
phenelzine increases toxicity of sufentanil SL by serotonin levels. Avoid or Use Alternate Drug. MAOI interactions with opioids may manifest as serotonin syndrome or opioid toxicity (eg, respiratory depression, coma). Opioids are not recommended for patients taking MAOIs or within 14 days of stopping MAOIs. If urgent opioid treatment needed, use test doses and frequent titration of small doses to treat pain while closely monitoring blood pressure and signs and symptoms of CNS and respiratory depression.
- sumatriptan
sumatriptan and phenelzine both increase serotonin levels. Avoid or Use Alternate Drug.
phenelzine increases levels of sumatriptan by decreasing metabolism. Contraindicated. - sumatriptan intranasal
sumatriptan intranasal and phenelzine both increase serotonin levels. Avoid or Use Alternate Drug.
phenelzine increases levels of sumatriptan intranasal by decreasing metabolism. Contraindicated. - tapentadol
phenelzine increases toxicity of tapentadol by unknown mechanism. Avoid or Use Alternate Drug. Risk of hypotension, hyperpyrexia, somnolence, or death; separate by 14 d.
- tedizolid
tedizolid, phenelzine. Either increases effects of the other by Mechanism: pharmacodynamic synergism. Avoid or Use Alternate Drug. Interaction with MAOIs were not studied in clinical trials; drugs within the same class(eg linezolid) are contraindicated with MAOIs.
- terbutaline
phenelzine increases effects of terbutaline by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.
- tramadol
phenelzine and tramadol both increase serotonin levels. Avoid or Use Alternate Drug.
phenelzine increases toxicity of tramadol by unknown mechanism. Avoid or Use Alternate Drug. Risk of hypotension, hyperpyrexia, somnolence, or death; separate by 14 d. - umeclidinium bromide/vilanterol inhaled
phenelzine and umeclidinium bromide/vilanterol inhaled both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Avoid or Use Alternate Drug. Exercise extreme caution if vilanterol coadministered with MAOIs or TCAs, or within 2 weeks of discontinuation of these drugs; adrenergic agonist effects on the cardiovascular system may be potentiated
- valbenazine
phenelzine, valbenazine. Other (see comment). Avoid or Use Alternate Drug. Comment: Coadministration of valbenazine with MAOIs may increase monoamine neurotransmitter concentration in synapses, potentially increasing risk of serotonin syndrome or attenuating valbenazine effect.
- vilanterol/fluticasone furoate inhaled
phenelzine and vilanterol/fluticasone furoate inhaled both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Avoid or Use Alternate Drug. Exercise extreme caution if vilanterol coadministered with MAOIs or TCAs, or within 2 weeks of discontinuation of these drugs; adrenergic agonist effects on the cardiovascular system may be potentiated
- zolmitriptan
zolmitriptan and phenelzine both increase serotonin levels. Avoid or Use Alternate Drug.
phenelzine increases levels of zolmitriptan by decreasing metabolism. Contraindicated.
Monitor Closely (87)
- aripiprazole
phenelzine, aripiprazole. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).
- asenapine
phenelzine, asenapine. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).
- benazepril
phenelzine, benazepril. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Increases risk of hypotension.
- bretylium
phenelzine increases effects of bretylium by sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Modify Therapy/Monitor Closely. Bretylium produces release of catecholamines from nerve endings. This increased catecholamine release is potentiated by MAOIs.
- brompheniramine
phenelzine increases effects of brompheniramine by Other (see comment). Modify Therapy/Monitor Closely. Comment: Coadministration of phenelzine and antihistamines may result in additive CNS depressant effects. MAO inhibitors also prolong and intensify anticholinergic effects of antihistamines. .
- bupivacaine implant
phenelzine, bupivacaine implant. Either increases toxicity of the other by Other (see comment). Use Caution/Monitor. Comment: Local anesthetics may increase the risk of developing methemoglobinemia when concurrently exposed to drugs that also cause methemoglobinemia.
- buprenorphine subdermal implant
phenelzine, buprenorphine subdermal implant. Either increases toxicity of the other by serotonin levels. Use Caution/Monitor. Concomitant use could result in life-threatening serotonin syndrome. If concomitant use is warranted, carefully observe the patient, particularly during treatment initiation, and during dose adjustment of the serotonergic drug. Discontinue buprenorphine if serotonin syndrome is suspected.
- buprenorphine, long-acting injection
phenelzine, buprenorphine, long-acting injection. Either increases toxicity of the other by serotonin levels. Modify Therapy/Monitor Closely. Concomitant use could result in life-threatening serotonin syndrome or opioid toxicity (eg, respiratory depression, coma). Buprenorphine long-acting injection is not recommended for patients taking MAOIs or within 14 days of stopping such treatment.
- captopril
phenelzine, captopril. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Both drugs lower blood pressure. Monitor blood pressure.
- carbinoxamine
phenelzine increases effects of carbinoxamine by Other (see comment). Modify Therapy/Monitor Closely. Comment: Coadministration of phenelzine and antihistamines may result in additive CNS depressant effects. MAO inhibitors also prolong and intensify anticholinergic effects of antihistamines. .
- cariprazine
phenelzine, cariprazine. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).
- cetirizine
phenelzine increases effects of cetirizine by Other (see comment). Modify Therapy/Monitor Closely. Comment: Coadministration of phenelzine and antihistamines may result in additive CNS depressant effects. MAO inhibitors also prolong and intensify anticholinergic effects of antihistamines. .
- chlorpheniramine
phenelzine increases effects of chlorpheniramine by Other (see comment). Modify Therapy/Monitor Closely. Comment: Coadministration of phenelzine and antihistamines may result in additive CNS depressant effects. MAO inhibitors also prolong and intensify anticholinergic effects of antihistamines. .
- chlorpropamide
phenelzine increases effects of chlorpropamide by unknown mechanism. Use Caution/Monitor.
- clemastine
phenelzine increases effects of clemastine by Other (see comment). Modify Therapy/Monitor Closely. Comment: Coadministration of phenelzine and antihistamines may result in additive CNS depressant effects. MAO inhibitors also prolong and intensify anticholinergic effects of antihistamines. .
- clozapine
phenelzine, clozapine. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).
- desloratadine
phenelzine increases effects of desloratadine by Other (see comment). Modify Therapy/Monitor Closely. Comment: Potential for dangerous interaction. Use with caution and monitor closely.
- dexchlorpheniramine
phenelzine increases effects of dexchlorpheniramine by Other (see comment). Modify Therapy/Monitor Closely. Comment: Coadministration of phenelzine and antihistamines may result in additive CNS depressant effects. MAO inhibitors also prolong and intensify anticholinergic effects of antihistamines. .
- dextroamphetamine transdermal
phenelzine, dextroamphetamine transdermal. Either increases effects of the other by serotonin levels. Modify Therapy/Monitor Closely. Initiate with lower doses and monitor for signs and symptoms of serotonin syndrome, particularly during initiation or dosage increase. If serotonin syndrome occurs, discontinue dextroamphetamine transdermal and concomitant serotonergic drug(s).
- diazepam intranasal
diazepam intranasal, phenelzine. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Coadministration may potentiate the CNS-depressant effects of each drug.
- dichlorphenamide
dichlorphenamide, phenelzine. Either increases toxicity of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Both drugs can cause metabolic acidosis.
- difenoxin hcl
difenoxin hcl, phenelzine. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Risk of serotonin syndrome.
- diphenhydramine
phenelzine increases effects of diphenhydramine by Other (see comment). Modify Therapy/Monitor Closely. Comment: Coadministration of phenelzine and antihistamines may result in additive CNS depressant effects. MAO inhibitors also prolong and intensify anticholinergic effects of antihistamines. .
- diphenoxylate hcl
diphenoxylate hcl, phenelzine. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Risk of serotonin syndrome.
- donepezil transdermal
donepezil transdermal, phenelzine. Either decreases effects of the other by pharmacodynamic antagonism. Use Caution/Monitor.
- doxylamine
phenelzine increases effects of doxylamine by Other (see comment). Modify Therapy/Monitor Closely. Comment: Coadministration of phenelzine and antihistamines may result in additive CNS depressant effects. MAO inhibitors also prolong and intensify anticholinergic effects of antihistamines. .
- esketamine intranasal
esketamine intranasal, phenelzine. Either increases toxicity of the other by sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor. Closely monitor blood pressure with concomitant use of esketamine nasal with MAO-Is. .
- etomidate
phenelzine increases levels of etomidate by pharmacodynamic synergism. Use Caution/Monitor.
- fexofenadine
phenelzine increases effects of fexofenadine by Other (see comment). Modify Therapy/Monitor Closely. Comment: Coadministration of phenelzine and antihistamines may result in additive CNS depressant effects. MAO inhibitors also prolong and intensify anticholinergic effects of antihistamines. .
- fluphenazine
phenelzine, fluphenazine. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).
- gabapentin
gabapentin, phenelzine. 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 enacarbil
gabapentin enacarbil, phenelzine. 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.
- ganaxolone
phenelzine and ganaxolone both increase sedation. Use Caution/Monitor.
- glimepiride
phenelzine increases effects of glimepiride by unknown mechanism. Use Caution/Monitor.
- glipizide
phenelzine increases effects of glipizide by unknown mechanism. Use Caution/Monitor.
- glyburide
phenelzine increases effects of glyburide by unknown mechanism. Use Caution/Monitor.
- green tea
green tea, phenelzine. Other (see comment). Use Caution/Monitor. Comment: Avoid combination or excessive consumption of green tea. Combination may increase risk of cardiac arrhythmias or severe hypertension can occur due to caffeine component of green tea.
- haloperidol
phenelzine, haloperidol. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).
- hydralazine
hydralazine, phenelzine. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Risk of hypertension.
- hydroxyzine
phenelzine increases effects of hydroxyzine by Other (see comment). Modify Therapy/Monitor Closely. Comment: Coadministration of phenelzine and antihistamines may result in additive CNS depressant effects. MAO inhibitors also prolong and intensify anticholinergic effects of antihistamines. .
- iloperidone
phenelzine, iloperidone. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).
- indacaterol, inhaled
indacaterol, inhaled, phenelzine. QTc interval. Use Caution/Monitor. Indacaterol should be administered with extreme caution to patients treated with MAO inhibitors. Drugs that are known to prolong the QTc interval may have an increased the risk of ventricular arrhythmias.
- insulin aspart
phenelzine increases effects of insulin aspart by unknown mechanism. Use Caution/Monitor.
- insulin degludec
phenelzine, insulin degludec. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Both drugs decrease blood glucose.
- insulin degludec/insulin aspart
phenelzine, insulin degludec/insulin aspart. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Both drugs decrease blood glucose.
- insulin detemir
phenelzine increases effects of insulin detemir by unknown mechanism. Use Caution/Monitor.
- insulin glargine
phenelzine increases effects of insulin glargine by unknown mechanism. Use Caution/Monitor.
- insulin glulisine
phenelzine increases effects of insulin glulisine by unknown mechanism. Use Caution/Monitor.
- insulin inhaled
phenelzine, insulin inhaled. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Both drugs decrease blood glucose.
- insulin lispro
phenelzine increases effects of insulin lispro by unknown mechanism. Use Caution/Monitor.
- insulin NPH
phenelzine increases effects of insulin NPH by unknown mechanism. Use Caution/Monitor.
- insulin regular human
phenelzine increases effects of insulin regular human by unknown mechanism. Use Caution/Monitor.
- lasmiditan
lasmiditan, phenelzine. 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.
phenelzine increases effects of lasmiditan by serotonin levels. Use Caution/Monitor. Coadministration may increase risk of serotonin syndrome. - lemborexant
lemborexant, phenelzine. 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.
- levocetirizine
phenelzine increases effects of levocetirizine by Other (see comment). Modify Therapy/Monitor Closely. Comment: Coadministration of phenelzine and antihistamines may result in additive CNS depressant effects. MAO inhibitors also prolong and intensify anticholinergic effects of antihistamines. .
- lithium
lithium, phenelzine. Mechanism: unknown. Use Caution/Monitor. Risk of malignant hyperpyrexia. Interactions esp. expected w/non selective MAOIs.
- loratadine
phenelzine increases effects of loratadine by Other (see comment). Modify Therapy/Monitor Closely. Comment: Coadministration of phenelzine and antihistamines may result in additive CNS depressant effects. MAO inhibitors also prolong and intensify anticholinergic effects of antihistamines. .
- loxapine
phenelzine, loxapine. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).
- loxapine inhaled
phenelzine, loxapine inhaled. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).
- lurasidone
lurasidone increases effects of phenelzine by Other (see comment). Use Caution/Monitor. Comment: Potential for increased risk of hypotension with concurrent use. Monitor blood pressure and adjust dose of antihypertensive agent as needed.
lurasidone, phenelzine. Either increases toxicity of the other by sedation. Use Caution/Monitor. Potential for increased CNS depressant effects when used concurrently; monitor for increased adverse effects and toxicity.
phenelzine, lurasidone. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction). - metformin
phenelzine will increase the level or effect of metformin by unspecified interaction mechanism. Use Caution/Monitor.
- metrizamide
phenelzine, metrizamide. Mechanism: unspecified interaction mechanism. Use Caution/Monitor. Risk of seizure. D/C MAO inhibitor 24h before admin. of metrizamide.
- molindone
phenelzine, molindone. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).
- olanzapine
phenelzine, olanzapine. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).
- oliceridine
phenelzine, oliceridine. Either increases effects of the other by serotonin levels. Modify Therapy/Monitor Closely. If concomitant use is warranted, carefully monitor, particularly during treatment initiation and dose adjustment. Discontinue oliceridine if serotonin syndrome is suspected. .
- olodaterol inhaled
phenelzine and olodaterol inhaled both increase QTc interval. Use Caution/Monitor. MAO inhibitors prolong the QTc interval and may potentiate the effects of beta2 agonists on the cardiovascular system; increased risk of ventricular arrhythmias
- opium tincture
opium tincture, phenelzine. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Risk of serotonin syndrome.
- oxymetazoline topical
oxymetazoline topical and phenelzine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.
- paliperidone
phenelzine, paliperidone. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).
- perphenazine
phenelzine, perphenazine. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).
- phenylephrine ophthalmic
phenelzine increases effects of phenylephrine ophthalmic by pharmacodynamic synergism. Use Caution/Monitor. Some systemic absorption of ophthalmic phenylephrine; reduce dose within 21 days of MAO inhibitors.
- pimavanserin
phenelzine, pimavanserin. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).
- pimozide
phenelzine, pimozide. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).
- pregabalin
pregabalin, phenelzine. 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.
- promethazine
phenelzine increases effects of promethazine by Other (see comment). Modify Therapy/Monitor Closely. Comment: Coadministration of phenelzine and antihistamines may result in additive CNS depressant effects. MAO inhibitors also prolong and intensify anticholinergic effects of antihistamines. .
- quetiapine
phenelzine, quetiapine. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).
- remifentanil
remifentanil increases toxicity of phenelzine by serotonin levels. Modify Therapy/Monitor Closely. Increases risk of serotonin syndrome.
- remimazolam
remimazolam, phenelzine. 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.
- risperidone
phenelzine, risperidone. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).
- tapentadol
phenelzine and tapentadol both increase serotonin levels. Modify Therapy/Monitor Closely.
- thiothixene
phenelzine, thiothixene. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).
- tolazamide
phenelzine increases effects of tolazamide by unknown mechanism. Use Caution/Monitor.
- tolbutamide
phenelzine increases effects of tolbutamide by unknown mechanism. Use Caution/Monitor.
- trifluoperazine
phenelzine, trifluoperazine. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).
- valerian
valerian and phenelzine both increase sedation. Use Caution/Monitor.
- yohimbe
yohimbe increases effects of phenelzine by pharmacodynamic synergism. Use Caution/Monitor.
- ziprasidone
phenelzine, ziprasidone. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).
Minor (16)
- amobarbital
phenelzine increases levels of amobarbital by decreasing metabolism. Minor/Significance Unknown. Theoretical interaction.
- butabarbital
phenelzine increases levels of butabarbital by decreasing metabolism. Minor/Significance Unknown. Theoretical interaction.
- butalbital
phenelzine increases levels of butalbital by decreasing metabolism. Minor/Significance Unknown. Theoretical interaction.
- celandine
celandine increases effects of phenelzine by pharmacodynamic synergism. Minor/Significance Unknown. Based on animal studies.
- cordyceps
cordyceps increases effects of phenelzine by pharmacodynamic synergism. Minor/Significance Unknown.
- disulfiram
disulfiram, phenelzine. Mechanism: unknown. Minor/Significance Unknown. Risk of delirium (case report).
- panax ginseng
panax ginseng increases effects of phenelzine by pharmacodynamic synergism. Minor/Significance Unknown.
- pentobarbital
phenelzine increases levels of pentobarbital by decreasing metabolism. Minor/Significance Unknown. Theoretical interaction.
- phenobarbital
phenelzine increases levels of phenobarbital by decreasing metabolism. Minor/Significance Unknown. Theoretical interaction.
- pleurisy root
pleurisy root decreases effects of phenelzine by unspecified interaction mechanism. Minor/Significance Unknown. Theoretical interaction.
- primidone
phenelzine increases levels of primidone by decreasing metabolism. Minor/Significance Unknown. Theoretical interaction.
- secobarbital
phenelzine increases levels of secobarbital by decreasing metabolism. Minor/Significance Unknown. Theoretical interaction.
- succinylcholine
phenelzine increases levels of succinylcholine by decreasing metabolism. Minor/Significance Unknown.
- sulfadiazine
phenelzine increases levels of sulfadiazine by unspecified interaction mechanism. Minor/Significance Unknown.
- sulfamethoxazole
phenelzine increases levels of sulfamethoxazole by unspecified interaction mechanism. Minor/Significance Unknown.
- sulfisoxazole
phenelzine increases levels of sulfisoxazole by unspecified interaction mechanism. Minor/Significance Unknown.
Adverse Effects
Frequency Not Defined
Common
- Orthostatic hypotension
- Asthenia
- Dizziness
- Headache
- Drowsiness
- Fatigue
- Hyperreflexia
- Sleep disturbance
- Somnolence
- Weakness
- Tremor
- Constipation
- Dry mouth
- Weight gain
Less Common
- Confusion
- Decreased memory
- Paresthesia
- Anorexia
- Nausea
- Vomiting
- Impotence
- Increased LFT's
- Nystagmus
- Urinary frequency or retention
Uncommon
- Edema
- Anxiety
- Irritation
- Hypomania
- Hypermetabolic syndrome (hyperpyrexia, tachycardia, tachypnea, increased CPK, acidosis)
- Arthralgia
- SIADH
Rare
- Hypertensive crisis
- Ataxia
- Seizure
- Worsening depression
- Suicide
- Edema of glottis
- Leukopenia
- Hepatic necrosis, jaundice
- Drug-induced lupus erythematosus
- Visual disturbance
Warnings
Black Box Warnings
In short-term studies, antidepressants increased the risk of suicidal thinking and behavior in children, adolescents, and young adults (<24 yr of age) taking antidepressants for major depressive disorders and other psychiatric illnesses
This increase was not seen in patients aged >24 years; a slight decrease in suicidal thinking was seen in adults >65 years
In children and young adults, risks must be weighed against the benefits of taking antidepressants
Patients should be monitored closely for changes in behavior, clinical worsening, and suicidal tendencies; this should be done during initial 1-2 months of therapy and dosage adjustments
The patient’s family should communicate any abrupt changes in behavior to the healthcare provider
Worsening behavior and suicidal tendencies that are not part of the presenting symptoms may require discontinuation of therapy
This drug is not approved for use in pediatric patients
Contraindications
Hypersensitivity
Pheochromocytoma, congestive heart failure
Within 10 days of elective surgery using general anesthesia or spinal anesthesia
Liver disease, abnormal liver function tests, or history of hepatic disease
Renal disease, severe renal impairment, ESRD
Cautions
Orthostatic hypotension may occur
Hypertensive reactions may occur from consumption of foods high in tyramine or supplements containing caffeine, tyrosine, tryptophan, phenylalanine, or phenylalanine
Not first-line therapy
Discontinue 10 days before surgery
Therapy not approved for treating any indications in the pediatric population
Most serious reactions involve changes in blood pressure
Therapy may cause excessive stimulation in schizophrenic patients
Drug potentiates hexobarbital hypnosis in animals; barbiturates should be given at a reduced dose with phenelzine
Drug should be used with caution in diabetes mellitus; increased insulin sensitivity may occur; requirements for insulin or oral hypoglycemics may be decreased; there is conflicting evidence as to whether or not MAO inhibitors affect glucose metabolism or potentiate hypoglycemic agents; this should be kept in mind if drug is administered to diabetics
Hypertensive crises
- Most important reaction associated with therapy is the occurrence of hypertensive crises, which have sometimes been fatal
- The crises are characterized by occipital headache which may radiate frontally, palpitation, neck stiffness or soreness, nausea, vomiting, sweating (sometimes with fever and sometimes with cold, clammy skin), dilated pupils, and photophobia; either tachycardia or bradycardia may be present and can be associated with constricting chest pain
- Intracranial bleeding has been reported in association with increase in blood pressure; blood pressure should be observed frequently to detect evidence of any pressor response in all patients receiving therapy; therapy should be discontinued immediately upon occurrence of palpitation or frequent headaches during therapy
- If a hypertensive crisis occurs, drug should be discontinued immediately and therapy to lower blood pressure should be instituted immediately; on the basis of present evidence, phentolamine is recommended; dosage reported for phentolamine is 5 mg intravenously; care should be taken to administer this drug slowly in order to avoid producing an excessive hypotensive effect; fever should be managed by means of external cooling
Suicide risk
- Patients with major depressive disorder (MDD), both adult and pediatric, may experience worsening of their depression and/or the emergence of suicidal ideation and behavior (suicidality) or unusual changes in behavior, whether or not they are taking antidepressant medications, and this risk may persist until significant remission occurs
- Unknown whether the suicidality risk extends to longer-term use, ie, beyond several months; however, there is substantial evidence from placebo-controlled maintenance trials in adults with depression that the use of antidepressants can delay the recurrence of depression
- All patients being treated with antidepressants for any indication should be monitored appropriately and observed closely for clinical worsening, suicidality, and unusual changes in behavior, especially during the initial few months of a course of drug therapy, or at times of dose changes, either increases or decrease
- The following symptoms, anxiety, agitation, panic attacks, insomnia, irritability, hostility, aggressiveness, impulsivity, akathisia (psychomotor restlessness), hypomania, and mania, reported in adult and pediatric patients being treated with antidepressants for major depressive disorder as well as for other indications, both psychiatric and nonpsychiatric; although a causal link between emergence of such symptoms and either the worsening of depression and/or emergence of suicidal impulses has not been established, there is concern that such symptoms may represent precursors to emerging suicidality
- Consider changing the therapeutic regimen, including possibly discontinuing the medication, in patients whose depression is persistently worse, or who are experiencing emergent suicidality or symptoms that might be precursors to worsening depression or suicidality, especially if these symptoms are severe, abrupt in onset, or were not part of the patient's presenting symptoms
- Families and caregivers of patients being treated with antidepressants for major depressive disorder or other indications, both psychiatric and nonpsychiatric, should be alerted about need to monitor patients for emergence of agitation, irritability, unusual changes in behavior; monitoring should include daily observation by families and caregivers; prescriptions should be written for smallest quantity of tablets consistent with good patient management, in order to reduce risk of overdose
Bipolar disorder
- A major depressive episode may be initial presentation of bipolar disorder; it is generally believed that treating such an episode with an antidepressant alone may increase likelihood of precipitation of a mixed/manic episode in patients at risk for bipolar disorder; whether any of the symptoms of depression described represent such a conversion is unknown
- Of the more severe side effects reported with any consistency, hypomania has been the most common; this reaction has been largely limited to patients in whom disorders characterized by hyperkinetic symptoms coexist with, but are obscured by, depressive affect; hypomania usually appeared as depression improved; if agitation is present, may be increased with therapy; hypomania and agitation have also been reported at higher than recommended doses or following long-term therapy
- Prior to initiating treatment with an antidepressant, patients with depressive symptoms should be adequately screened to determine if they are at risk for bipolar disorder; such screening should include a detailed psychiatric history, including a family history of suicide, bipolar disorder, and depression; therapy is not approved to treat bipolar depression
Drug interaction overview
- In patients receiving nonselective monoamine oxidase (MAO) inhibitors in combination with serotoninergic agents there have been reports of serious, sometimes fatal, reactions; phenelzine should not be used concomitantly with a serotoninergic agent
- Administration of guanethidine to patients receiving a MAO inhibitor can produce moderate to severe hypertension due to release of catecholamines; at least two weeks should elapse between withdrawal of MAO inhibitor and initiation of guanethidine
Pregnancy & Lactation
Pregnancy Category: C
Lactation: unknown; use caution
Pregnancy Categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk. C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done. D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk. X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist. NA: Information not available.Pharmacology
Mechanism of Action
Nonselective monoamine oxidase inhibitor; may inhibit the enzyme monoamine oxidase, which is responsible for the breakdown of dopamine, serotonin, epinephrine, and norepinephrine, in turn causing an increase in endogenous concentrations of these neurotransmitters.
Pharmacokinetics
Peak Plasma Time: 43 min
Metabolism: by MAO
Onset of action: 2-4 weeks
Duration: Therapeutic effects and interactions may continue for up to 2 weeks after discontinuing therapy
Metabolites: phenylacetic acid & parahydroxyphenylacetic acid
Half-Life, Elimination: 11.6 hr
Excretion: Urine
Images
| BRAND | FORM. | UNIT PRICE | PILL IMAGE |
|---|---|---|---|
| phenelzine oral - | 15 mg tablet |  | |
| phenelzine oral - | 15 mg tablet |  | |
| Nardil oral - | 15 mg tablet | |
Copyright © 2010 First DataBank, Inc.
Patient Handout
phenelzine oral
PHENELZINE - ORAL
(FEN-el-zeen)
COMMON BRAND NAME(S): Nardil
WARNING: Antidepressant medications are used to treat a variety of conditions, including depression and other mental/mood disorders. These medications can help prevent suicidal thoughts/attempts and provide other important benefits. However, studies have shown that a small number of people (especially people younger than 25) who take antidepressants for any condition may experience worsening depression, other mental/mood symptoms, or suicidal thoughts/attempts. It is very important to talk with the doctor about the risks and benefits of antidepressant medication (especially for people younger than 25), even if treatment is not for a mental/mood condition.Tell the doctor right away if you notice worsening depression/other psychiatric conditions, unusual behavior changes (including possible suicidal thoughts/attempts), or other mental/mood changes (including new/worsening anxiety, panic attacks, trouble sleeping, irritability, hostile/angry feelings, impulsive actions, severe restlessness, very rapid speech). Be especially watchful for these symptoms when a new antidepressant is started or when the dose is changed.
USES: Phenelzine is an antidepressant (monoamine oxidase inhibitor). This medication treats depression by restoring the balance of certain natural substances (neurotransmitters) in the brain. Phenelzine can improve your mood and feelings of well-being. Usually, this medication is used in persons who have not responded to treatment with other drugs.
HOW TO USE: Read the Medication Guide available from your pharmacist before you start using phenelzine and each time you get a refill. If you have any questions, consult your doctor or pharmacist.Take this medication by mouth with or without food as directed by your doctor, usually 1 to 3 times a day. The dosage is based on your medical condition and response to treatment.To reduce your risk of side effects, your doctor may start you at a low dose and gradually increase your dose. Once your condition improves and you are better for a while, your doctor may work with you to reduce your regular dose. Follow your doctor's instructions carefully. Do not take more or less medication or take it more often than prescribed. Your condition will not improve any faster and your risk of side effects will increase.Use this medication regularly in order to get the most benefit from it. To help you remember, use it at the same time(s) each day. It may take several weeks for the full benefits of this medication to be noticed. Do not stop taking this medication without consulting your doctor.If you suddenly stop using this medication, you may have withdrawal symptoms (such as restlessness, confusion, hallucinations, headache, weakness, and diarrhea). To help prevent withdrawal, your doctor may lower your dose slowly. Withdrawal is more likely if you have used phenelzine for a long time or in high doses. Tell your doctor or pharmacist right away if you have withdrawal.Inform your doctor if your condition lasts or gets worse.
SIDE EFFECTS: See also Warning section.Dizziness, drowsiness, tiredness, weakness, problems sleeping, constipation, and dry mouth may occur. If any of these effects last or get worse, notify your doctor or pharmacist promptly.Remember that this medication has been prescribed because your doctor has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.Tell your doctor right away if you have any serious side effects, including: fainting, mental/mood changes (such as agitation, confusion), muscle stiffness, changes in sexual ability/interest, shaking (tremor), shivering, swollen ankles/legs, unusual weight gain, eye pain/swelling/redness, vision changes (such as double/blurred vision), signs of liver problems (such as nausea/vomiting that doesn't stop, stomach/abdominal pain, yellowing eyes/skin, dark urine), seizures.This drug may rarely cause an attack of extremely high blood pressure (hypertensive crisis), which may be fatal. Many drug and food interactions can increase this risk (See also Drug Interaction section.) Stop taking phenelzine and get medical help right away if any of these serious side effects occur: frequent/severe headache, fast/slow/irregular/pounding heartbeat, chest pain, neck stiffness/soreness, severe nausea/vomiting, sweating/clammy skin (sometimes with fever), widened pupils, sudden sensitivity to light (photophobia).This medication may increase serotonin and rarely cause a very serious condition called serotonin syndrome/toxicity. The risk increases if you are also taking other drugs that increase serotonin, so tell your doctor or pharmacist of all the drugs you take (see Drug Interactions section). Get medical help right away if you develop some of the following symptoms: fast heartbeat, hallucinations, loss of coordination, severe dizziness, severe nausea/vomiting/diarrhea, twitching muscles, unexplained fever, unusual agitation/restlessness.A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), dizziness, trouble breathing.This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.In the US -Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.
PRECAUTIONS: Before taking phenelzine, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.Before using this medication, tell your doctor or pharmacist your medical history, especially of: a certain kind of adrenal gland tumor (pheochromocytoma), cerebrovascular disease (such as stroke), heart problems (such as heart failure, heart attack, coronary artery disease), high blood pressure, history of severe/frequent headaches, liver problems, kidney disease, personal/family history of mental/mood disorders (such as schizophrenia, bipolar disorder), diabetes, certain nervous system diseases (Parkinson's syndrome, seizures), overactive thyroid (hyperthyroidism), personal/family history of glaucoma (angle-closure type).This drug may make you dizzy or drowsy. Alcohol or marijuana (cannabis) can make you more dizzy or drowsy. Do not drive, use machinery, or do anything that needs alertness until you can do it safely. Avoid alcoholic beverages. Talk to your doctor if you are using marijuana (cannabis).To minimize dizziness and the risk of fainting, get up slowly when rising from a sitting or lying position.Before having surgery or any procedures requiring use of contrast dye (such as myelography), tell your doctor or dentist you are on this medication. You may need to stop taking this drug beforehand. Follow your doctor's instructions carefully.If you have heart disease, this medication may mask chest pain. Avoid strenuous exercise while taking this medication.If you have diabetes, phenelzine may lower your blood sugar. Check your blood sugar regularly as directed and share the results with your doctor. Tell your doctor right away if you have symptoms of low blood sugar such as sudden sweating, shaking, fast heartbeat, hunger, blurred vision, dizziness, or tingling hands/feet. Your doctor may need to adjust your diabetes medication, exercise program, or diet.Older adults may be more sensitive to the side effects of this drug, especially the effects on blood pressure.During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor.Since untreated mental/mood problems (such as depression) can be a serious condition, do not stop taking this medication unless directed by your doctor. If you are planning pregnancy, become pregnant, or think you may be pregnant, immediately discuss with your doctor the benefits and risks of using this medication during pregnancy.It is unknown if this drug passes into breast milk. Consult your doctor before breast-feeding.
DRUG INTERACTIONS: Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.Some products that may interact with this drug include: other antidepressants (including maprotiline, mirtazapine, nefazodone, TCAs such as amitriptyline/nortriptyline), appetite suppressants (such as diethylpropion), drugs for attention deficit disorder (such as atomoxetine, methylphenidate), apraclonidine, bupropion, buspirone, carbamazepine, cyclobenzaprine, deutetrabenazine, dextromethorphan, certain drugs for high blood pressure (such as guanethidine, methyldopa, beta blockers such as atenolol, clonidine, rauwolfia alkaloids), other MAO inhibitors (isocarboxazid, linezolid, metaxalone, methylene blue, moclobemide, procarbazine, rasagiline, safinamide, selegiline, tranylcypromine), metoclopramide, certain opioid medications (such as fentanyl, meperidine, methadone, tapentadol), certain drugs for Parkinson's (such as entacapone, levodopa, tolcapone), street drugs (such as LSD, mescaline), stimulants (such as amphetamines, cocaine, dopamine, epinephrine, phenylalanine), tetrabenazine, "triptan" migraine drugs (such as sumatriptan, rizatriptan), tramadol, tyrosine, tryptophan, valbenazine.The risk of serotonin syndrome/toxicity increases if you are also taking other drugs that increase serotonin. Examples include street drugs such as MDMA/ "ecstasy," St. John's wort, certain antidepressants (including SSRIs such as fluoxetine/paroxetine, SNRIs such as duloxetine/venlafaxine), among others. The risk of serotonin syndrome/toxicity may be more likely when you start or increase the dose of these drugs.Tell your doctor or pharmacist if you are using any of these medications before, during, or within 2 weeks after treatment with phenelzine. Tell your doctor or pharmacist if you have taken fluoxetine during at least 5 weeks before starting phenelzine. Discuss with your doctor how much time to wait between starting or stopping any of these drugs and taking phenelzine.Tell your doctor or pharmacist if you are taking other products that cause drowsiness such as opioid pain or cough relievers (such as codeine, hydrocodone), alcohol, marijuana (cannabis), drugs for sleep or anxiety (such as alprazolam, lorazepam, zolpidem), muscle relaxants (such as carisoprodol, cyclobenzaprine), or antihistamines (such as cetirizine, diphenhydramine).Check the labels on all your medicines (such as allergy, cough-and-cold products, decongestants, diet pills) because they may contain dextromethorphan, decongestants, stimulants, or ingredients that cause drowsiness. Ask your pharmacist about the safe use of those products.It is very important that you follow special dietary restrictions in order to limit the amount of tyramine in your diet. Avoid drinking large amounts of beverages containing caffeine (coffee, tea, colas) or eating large amounts of chocolate. Caffeine can increase the side effects of this medication. Foods and beverages high in tyramine should be avoided while you are taking this medication and for at least 2 weeks after you stop using this medication.Foods high in tyramine include: aged cheeses (cheddar, camembert, emmenthaler, brie, stilton blue, gruyere, gouda, brick, bleu, roquefort, boursault, parmesan, romano, provolone, liederdranz, colby, edam), aged/dried/fermented/salted/smoked/pickled/processed meats and fish (includes bacon, summer sausage, liverwurst, hot dogs, corned beef, pepperoni, salami, bologna, ham, mortadella, pickled or dried herring), banana peel, beef/chicken liver (stored, not fresh), bouillon cubes, commercial gravies, concentrated yeast extracts, fava beans, Italian green beans, broad beans, fermented bean curd, homemade yeast-leavened bread, kim chee (Korean fermented cabbage), orange pulp, overripe or spoiled fruits, packaged soups, red wine, sauerkraut, sherry, snow pea pods, sourdough bread, soy sauce, soybeans, soybean paste/miso, tofu, tap beer and ale, vermouth.Moderate-to-low tyramine content foods include: alcohol-free beer, avocados, bananas, bottled beer and ale, chocolate and products made with chocolate, coffee, cola, cultured dairy products (such as buttermilk, yogurt, sour cream), distilled spirits, eggplant, canned figs, fish roe (caviar), green bean pods, pate, peanuts, port wine, raisins, raspberries, red plums, spinach, tomatoes, white wine.Tell your doctor or pharmacist right away if you notice symptoms of high blood pressure such as fast/slow heartbeat, vomiting, sweating, headache, chest pain, sudden vision changes, weakness on one side of the body, or trouble speaking.Contact your healthcare professionals (such as doctor, pharmacist, dietician) for more information, including recommendations for your diet.
OVERDOSE: If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center.
NOTES: Do not share this medication with others.Lab and/or medical tests (such as blood pressure, liver function) should be done while you are taking this medication. Keep all medical and lab appointments. Consult your doctor for more details.
MISSED DOSE: If you miss a dose, take as soon as you remember unless the next scheduled dose is within 2 hours. In that case, skip the missed dose. Take your next dose at the regular time. Do not double the dose to catch up.
STORAGE: Store at room temperature away from light and moisture. Do not store in the bathroom. Keep all medications away from children and pets.Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.
MEDICAL ALERT: Your condition can cause complications in a medical emergency. For information about enrolling in MedicAlert, call 1-888-633-4298 (US) or 1-800-668-1507 (Canada).
Information last revised May 2023. Copyright(c) 2023 First Databank, Inc.
IMPORTANT: HOW TO USE THIS INFORMATION: This is a summary and does NOT have all possible information about this product. This information does not assure that this product is safe, effective, or appropriate for you. This information is not individual medical advice and does not substitute for the advice of your health care professional. Always ask your health care professional for complete information about this product and your specific health needs.
Formulary
Adding plans allows you to compare formulary status to other drugs in the same class.
To view formulary information first create a list of plans. Your list will be saved and can be edited at any time.
Adding plans allows you to:
- View the formulary and any restrictions for each plan.
- Manage and view all your plans together – even plans in different states.
- Compare formulary status to other drugs in the same class.
- Access your plan list on any device – mobile or desktop.
