Isocarboxazid (MARPLAN)
Isocarboxazid (MARPLAN)
Patients taking MAOIs (with the exception of the low strength EMSAM patch) must avoid tyramine-rich foods. The list of forbidden foods is long. Failure to adhere to a low tyramine diet may lead to what was originally called the “cheese effect”, a potentially fatal hypertensive crisis.
Tyramine is broken down by monoamine oxidase (MAO), which by definition MAOIs block. Without functioning MAO enzymes, tyramine accumulates and raises blood pressure.
The “tire rim” mnemonic can keep you from confusing tyramine with the amino acid tyrosine.
Note that if a patient is taking an oral MAOI for depression, phenelzine (Nardil) is the most likely prescription. Isocarboxazid (Marplan) scripts are exceedingly rare—it is the least prescribed of all antidepressants.
Dosing: Target dose is 20–60 mg/day divided BID–QID: Start 10 mg BID; May increase by 10 mg/day every 2–4 days; Max is 60 mg/day (20 mg TID or 30 mg BID); Taper gradually to stop.