An MAOI class interaction is any supplement pattern that overlaps with monoamine oxidase inhibitor medications, a small but high-stakes prescription class where co-ingestion errors can produce severe hypertensive or serotonergic events. The platform treats MAOI flags as absolute rather than relative — a matched pair holds the supplement out of activation entirely until a prescriber explicitly clears it.
Why the class is high-stakes
Many MAOIs irreversibly or non-selectively inhibit the enzymes that clear monoamines such as tyramine, dopamine, and serotonin. When a dietary or supplement source raises monoamine levels on top of this inhibition, the result can be a sharp blood pressure rise or, in the case of serotonergic loading, a toxicity syndrome. The window is narrow and the failure mode can be fast, which is why the platform does not offer a "proceed with monitoring" path for this class.
Supplements most commonly flagged
Serotonergic precursors and modulators are absolute holds against an MAOI. The list includes 5-HTP, tryptophan, St. John's Wort, and high-dose saffron extracts. See serotonergic interaction for the symptom-escalation rules that follow if a pair is taken before the platform flag is acknowledged.
Tyramine-adjacent inputs are a separate flag. Product labels that include fermented concentrates, aged extracts, or stimulant formulas are routed to prescriber review because the medication-specific restriction is stricter than a general supplement caution.
Why "non-selective" matters
Older MAOIs are non-selective and irreversible — their effect persists for weeks after the last dose. Newer reversible inhibitors of MAO-A and selective MAO-B inhibitors used in movement disorders carry a narrower but still real risk profile. The platform stores the specific medication rather than a generic class label so the screen matches the prescription on the user's chart.
For first-time stack builders on any MAOI, the pillar overview at building your first supplement stack covers why the platform shows a much shorter candidate list once an MAOI prescription is in the profile.
Wash-out windows
Stopping an MAOI does not immediately clear the flag. Irreversible inhibitors require an extended wash-out for enzyme regeneration; reversible inhibitors clear faster but still carry a documented transition window. The platform extends the hold across this window rather than reactivating on the last prescription date, and the prescribing clinician sets the actual duration.
What the flag preserves
The relevant record is the specific product label, any standardized extract content, the medication class, and the reason the pair was flagged. Some pairs are not treated as dose-adjustable in public safety references.
How this appears in Unfair
An MAOI prescription in the user profile triggers a class-wide screen and blocks activation for matched supplements with a clinician-question template pre-filled. The screen extends across the wash-out window after the prescription stops.
Clinical safety note
Severe headache, chest pain, rapid heart rate, or symptoms suggestive of serotonin toxicity are outside the scope of a glossary entry or supplement journal.