MAOIs structurally resemble and inhibit B6-dependent enzyme systems. Phenelzine specifically is a hydrazine derivative that forms inactive complexes with pyridoxal phosphate, functionally depleting active B6 in neurons.
Heller & Friedman (Am J Psychiatry, 1983) — phenelzine causes peripheral neuropathy reversed by B6 supplementation. B6 deficiency from MAOI hydrazine derivatives confirmed in multiple clinical reports.
Peripheral neuropathy (a known phenelzine side effect), depression paradox (B6 is required for serotonin synthesis that MAOIs are supposed to enhance), insomnia
P5P (pyridoxal-5-phosphate) 25–50mg daily. Use P5P not pyridoxine — phenelzine blocks pyridoxine-to-P5P conversion.
View on Fullscript: Thorne P-5-P (Pyridoxal 5'-Phosphate)Discuss with your physician before adjusting supplementation. This is educational content, not medical advice.
MAOIs inhibit MAO-A which also metabolizes serotonin — the precursor to melatonin. The net effect is complex: MAOIs may increase or decrease melatonin depending on timing and specific drug. Selegiline (MAO-B selective) has less melatonin interaction than non-selective MAOIs.
MAOIs affect the serotonin-to-melatonin pathway. Clinical sleep disruption is a documented MAOI side effect consistent with circadian melatonin alteration.
Sleep disturbance, circadian disruption
Low-dose melatonin 0.3–1mg — use cautiously given complex serotonin interactions with MAOIs. Discuss with prescriber.
View on Fullscript: Pure Encapsulations Melatonin 0.5mg — discuss with prescriberDiscuss with your physician before adjusting supplementation. This is educational content, not medical advice.
MAOIs block MAO-A in the gut and liver, which normally metabolizes dietary tyramine. Tyramine accumulation causes hypertensive crisis — potentially fatal. This is a dietary interaction, not a nutrient depletion per se, but it is the most critical nutrition-related concern with MAOI therapy.
The tyramine-MAOI hypertensive crisis is the most well-documented dietary drug interaction in medicine. Multiple fatalities documented. All MAOI prescribing requires detailed dietary counseling.
Hypertensive crisis (severe headache, palpitations, sweating, potentially fatal stroke or MI from blood pressure surge)
AVOID: aged cheeses, cured meats, fermented foods, draft beer, soy sauce, and any aged/fermented product. This dietary restriction is non-negotiable with MAOI therapy.
View on Fullscript: Strict dietary counseling required — discuss with prescriberDiscuss with your physician before adjusting supplementation. This is educational content, not medical advice.
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