MAOIs (Phenelzine, Tranylcypromine)
Common brand names: Nardil, Parnate, Emsam, Eldepryl, Azilect
Three nutrients listed against this medication. The most severe is marked critical.
At a glance
Two of the three are marked well documented. The other one carries its own evidence level.
At a glance
- Tyramine (dietary, CRITICAL)Critical · Well documented
- Vitamin B6 (P5P)Moderate · Well documented
- MelatoninMild · Traditionally cited, limited evidence
Color shows how serious each listed effect is. The label beside it shows how strong the evidence is. The cards below explain each one and show its evidence.
Nutrients it can lower
Mechanism, Phenelzine (a hydrazine derivative) forms inactive complexes with pyridoxal phosphate, functionally depleting active B6 in neurons.
Common signs, Peripheral neuropathy, depression paradox, insomnia
Heller et al. (Am J Med, 1983; PMID PubMed ID: the permanent number the US National Library of Medicine gives a published paper. Each one links to that paper's record on PubMed. 6638055): pyridoxine (B6) deficiency with peripheral neuropathy during long-term phenelzine, an MAOI.
P5P (the active form) was used at 25–50 mg daily. P5P is used rather than pyridoxine, since phenelzine blocks the pyridoxine-to-P5P conversion.
Mechanism, MAOIs inhibit monoamine oxidase, which breaks down serotonin, the precursor melatonin is made from. Blocking that breakdown tends to raise the precursor pool rather than lower melatonin. Sleep disruption on MAOIs is well recognized but has not been shown to be a melatonin deficiency.
Common signs, Sleep disturbance, circadian disruption
MAO inhibition tends to raise serotonin/melatonin precursors rather than deplete melatonin; sleep disruption on MAOIs is not a melatonin deficiency. Theoretical only.
Low-dose melatonin 0.3–1 mg was used cautiously, given complex serotonin interactions with MAOIs; this is discussed with the prescriber.
Mechanism, MAOIs block MAO-A in the gut and liver, which normally metabolizes dietary tyramine. Tyramine accumulation causes hypertensive crisis. Potentially fatal.
Common signs, Hypertensive crisis (severe headache, palpitations, sweating, potentially fatal stroke or MI)
McCabe (J Am Diet Assoc, 1986): review of dietary tyramine and pressor amines in MAOI regimens, the source of the standard diet-planning guidance for this interaction.
Tyramine-rich foods (aged cheeses, cured meats, fermented foods, draft beer, soy sauce) are avoided; this dietary restriction is strictly required with MAOI therapy.
For your next appointment
It prints or saves as a single page. Whether to add a supplement for a nutrient this medication may lower is a decision for your prescriber.
Disclosure
These statements have not been evaluated by the Food and Drug Administration. Any grade on this page describes the strength of published human trial evidence in the populations studied. It is not a recommendation for any individual and is not medical advice. Starting, stopping or changing any supplement or medication is a decision for your physician.
Grades move when new trials publish. A free monthly email lists every grade EBL moved, with the reason and the trial behind it: the sign-up is on the Evidence Log →