Dietary tyramine load
Dietary tyramine load. Food that carries pressor amines produced by bacterial decarboxylation during ageing or fermentation. Harmless when gut and liver MAO-A destroy it. Not harmless when that enzyme is blocked.
Dietary L-dopa load. Food carrying levodopa, which is converted to dopamine and noradrenaline. This is why broad-bean PODS are on the MAOI list — the mechanism is L-dopa, not tyramine, and the distinction matters because it changes which part of the plant is the problem.
What acts on it
- Aged and mature cheese
— provides, strong
Walker et al. measured wide variation: many aged cheeses well above 6 mg per serving, some samples far higher, with the same named cheese varying between samples. Variability is the hazard — you cannot tell by looking. - Cured, dried and fermented meat
— provides, strong
Fermented and air-dried sausages are consistently high. Fresh meat is not a source; spoiled or improperly stored meat is. - Soy sauce and fermented soy
— provides, variable
Highly variable between products and brands. Ordinary soy sauce in a normal serving is usually modest; fermented soybean pastes and fermented bean curd can be high. - Yeast extract and brewer's yeast — provides, strong
- Tap (draught) and unpasteurised beer
— provides, variable
Bottled/canned commercial beer: low, and two standard drinks are generally regarded as acceptable in modern MAOI guidance. Tap, cask and home-brewed beer: unpredictable and occasionally high. Tailor et al. re-analysed the classic phenelzine + tap beer hypertensive case and confirmed pressor amines in the beer. - Sauerkraut, kimchi and fermented vegetables — provides, moderate
- Broad bean (fava) PODS
— provides, moderate
The mechanism is levodopa content in the pod, converted to dopamine and noradrenaline. The shelled bean itself is a much smaller concern. Stating this correctly is the difference between a workable diet and a needlessly restrictive one. - Anything aged, fermented, pickled, smoked or spoiled
— provides, variable
Tyramine is produced by bacterial decarboxylation of tyrosine. Freshness is the variable that matters; a food that was low last week can be high after poor storage.
What is affected by it
- Nothing in this dataset.
What a clean result means here
A clean result means NO DOCUMENTED INTERACTION IN THIS DATASET. It does not mean safe, and it is not a clearance. Most substances are not in this dataset at all, and for many pairs that are, nobody has ever studied the combination.
In this dataset
- Monoamine oxidase inhibition (prescription MAOIs, RIMAs, linezolid, methylene blue, harmala alkaloids)
- Serotonergic drugs and the serotonin-toxicity mechanism
- Dietary tyramine and L-dopa loads
- The major cytochrome P450 pathways: CYP3A4, CYP2D6, CYP1A2, CYP2C9, CYP2C19 — inhibition and induction
- P-glycoprotein inhibition and induction
- 11β-HSD2 inhibition (the licorice mechanism) and the potassium consequences that follow it
- QT prolongation as an additive pharmacodynamic axis
- Culinary seasonings and common foods with documented pharmacological activity
- A selected set of narrow-therapeutic-index drugs where those shifts matter most
Not in this dataset
- Any substance not named in this dataset — which is most substances. There are tens of thousands of marketed drugs and this table holds fewer than a hundred entries.
- Phase-2 conjugation (UGT, SULT, NAT2, COMT) except where a specific entry names it. The oilahuasca corpus turns heavily on phase 2 and this engine models it only in passing.
- Pharmacogenomics. CYP2D6 and CYP2C19 are strongly polymorphic; a poor metaboliser and an ultra-rapid metaboliser can have opposite outcomes from the same pair, and this engine does not know your genotype.
- Dose, timing, duration, formulation and route — all of which change whether a documented interaction is clinically real for you.
- Renal and hepatic impairment, age, pregnancy, and body composition.
- Additive sedation, respiratory depression, bleeding risk, hypoglycaemia and most other pharmacodynamic axes beyond the ones listed above.
- Herb–herb interactions outside the named entries, and essentially the whole botanical world: most plants have no interaction literature at all.
- Allergy, intolerance, and contamination or adulteration of unregulated products.
- Anything published after the last-reviewed date below.
72 substances, 20 mechanisms, 64 citations. Last reviewed . Primary literature (every DOI resolved against the Crossref API) and FDA drug labelling. There is no free, openly-licensed, comprehensive drug-interaction dataset to draw on; NLM retired its Drug Interaction API on 2024-01-02 and DrugBank's interaction set is a commercial licence.
References
- Walker SE, Shulman KI, Tailor SAN, Gardner D (1996). Tyramine Content of Previously Restricted Foods in Monoamine Oxidase Inhibitor Diets. Journal of Clinical Psychopharmacology. doi:10.1097/00004714-199610000-00007
- Shulman KI, Walker SE (1999). Refining the MAOI Diet. The Journal of Clinical Psychiatry. doi:10.4088/jcp.v60n0308
- Blackwell B (1963). Hypertensive crisis due to monoamine-oxidase inhibitors. The Lancet. doi:10.1016/S0140-6736(63)92743-0
- Blackwell B, Marley E, Price J, Taylor D (1967). Hypertensive Interactions Between Monoamine Oxidase Inhibitors and Foodstuffs. British Journal of Psychiatry. doi:10.1192/bjp.113.497.349
- Gardner DM, Shulman KI, Walker SE, Tailor SAN (1996). The making of a user friendly MAOI diet. The Journal of Clinical Psychiatry 57(3):99-104. PMID 8617704
- Gillman PK, Feinberg SS, Fochtmann LJ (2018). A reassessment of the safety profile of monoamine oxidase inhibitors: elucidating tired old tyramine myths. Journal of Neural Transmission. doi:10.1007/s00702-018-1932-y
- Shulman KI, Tailor SAN, Walker SE, Gardner DM (1997). Tap (Draft) Beer and Monoamine Oxidase Inhibitor Dietary Restrictions. The Canadian Journal of Psychiatry. doi:10.1177/070674379704200311
- Tailor SAN, Shulman KI, Walker SE, Moss J, Gardner D (1994). Hypertensive Episode Associated with Phenelzine and Tap Beer — A Reanalysis of the Role of Pressor Amines in Beer. Journal of Clinical Psychopharmacology. doi:10.1097/00004714-199402000-00002
Every DOI above was resolved against the Crossref API on 2026-09-09 and the returned title checked against the one printed here. Three DOIs in the first draft resolved to real but different papers and were corrected before publication.
Last reviewed . All interaction pages.