Food and medicine interaction
Aged, fermented and cured foods high in tyramine and MAO inhibitor antidepressants, such as phenelzine (Nardil)
EstablishedEvidence level: established. Shown in drug labeling or in controlled studies in people.
Last reviewed
What can happen
Eating high-tyramine foods while taking an MAO inhibitor can cause a sudden, dangerous rise in blood pressure, sometimes called the cheese reaction.
- Why it happens
- MAO inhibitors block the enzyme that normally breaks down tyramine in the gut and liver, so tyramine builds up and releases noradrenaline.
- At ordinary food amounts
- Yes, ordinary servings matter. MedlinePlus lists aged, smoked, improperly stored or spoiled meat, fish and cheese, alcoholic drinks and fermented yeast products among tyramine sources. Freshness matters because tyramine rises as foods age.
What to do
If you take an MAO inhibitor, follow the food list your prescriber or pharmacist gives you. Seek emergency care for a sudden severe headache, chest pain or a racing heart.
Never stop or change a prescribed medicine without talking to the prescriber.
Common questions
Can I have aged, fermented and cured foods high in tyramine while taking MAO inhibitors?
If you take an MAO inhibitor, follow the food list your prescriber or pharmacist gives you. Seek emergency care for a sudden severe headache, chest pain or a racing heart. Yes, ordinary servings matter. MedlinePlus lists aged, smoked, improperly stored or spoiled meat, fish and cheese, alcoholic drinks and fermented yeast products among tyramine sources. Freshness matters because tyramine rises as foods age.