Mechanism of action: Isocarboxazid balliculeVisual mnemonic: Isocarboxazid mascot “Ice box Mars plan” restricted dietary items with MAOIs Mao Zedong → MAO inhibitor
What it isIrreversible non-selective MAO inhibitor; depression.
Why this oneAn option when other MAOIs are not tolerated.
What limits itTyramine hypertensive crisis and serotonin syndrome, with a two-week washout each way. Rarely used, so pharmacy familiarity is low.
BOXED WARNING Suicidality — antidepressants increase risk of suicidal thinking/behavior in children, adolescents, and young adults; monitor closely. Not approved for pediatric use.
FDA dosing
Population
Start
Target
Max
Depression
Adults
10 mg BID
40 mg/day divided by end of week 1
60 mg/day divided BID-QID
Titration Increase by 10 mg every 2-4 days through week 1, then by up to 20 mg/week
Renal Contraindicated in severe renal impairment
Hepatic Contraindicated in liver disease or abnormal liver function tests
Instructions
Divide the daily dose into 2-4 doses
After maximum response, taper slowly over several weeks
Allow ≥1 week washout when switching to/from another MAOI or dibenzazepine, then start at half the usual dose
Discontinue ≥10 days before elective surgery requiring general anesthesia
Pregnancy Reproductive toxicity not adequately evaluated; use only if clearly needed. Antidepressant pregnancy registry available.
Lactation Undefined
Cost
Isocarboxazid (MARPLAN)
Strength
#/mo
generic $/mo
CostPlus
10 mg
tab
60 BID
not offered
NADAC is a voluntary CMS survey of what retail community pharmacies pay for the drugs they stock. Isocarboxazid is dispensed outside retail pharmacies, so it rarely appears on surveyed invoices.
Generic entryNo US generic
⚠ BOXED WARNING
Suicidal thoughts and behaviors in patients under 25