A patient on a non-selective MAOI eats aged cheese with red wine. Within an hour their blood pressure spikes hard enough to bleed the brain. Here is exactly why, and what to grab off the crash cart.
Hypertensive Emergency
220 / 130
Stage One
The case at the door
Read it once. Watch for the clue. Tap to see the move.
Patient
A 38-year-old man with treatment-refractory depression is brought to the ED 45 minutes after dinner. He ate a charcuterie board (aged cheddar, salami, soppressata) and shared a bottle of red wine. He now has a sudden splitting occipital headache, palpitations, sweating, and flushing.
Vitals: BP 224/132, HR 118, RR 22, T 37.4 C. Pupils dilated. He is anxious and nauseated. His outpatient medication list includes phenelzine.
What is happening, and what do you reach for?
Tyramine-induced hypertensive crisis
Phenelzine is a non-selective irreversible MAOI. With MAO disabled in his gut and liver, the tyramine in aged cheese, cured meat, and red wine bypassed first-pass metabolism, flooded sympathetic nerve terminals, and displaced a tidal wave of norepinephrine. The result is a sudden hypertensive emergency.
First move: IV phentolamine, a non-selective alpha blocker. It directly reverses the alpha-1 vasoconstriction driving the BP. Nitroprusside is the backup. A beta-blocker by itself would be a mistake here.
Stage Two
Four clues, one diagnosis
When any three of these line up in a stem, the answer is tyramine crisis. Stop hunting.
💊
MAOI on board
Phenelzine, tranylcypromine, or isocarboxazid. Refractory depression or atypical depression history.
🧀
Trigger meal < 1 hour
Aged cheese, cured meat, red wine, draft beer, soy sauce, or fermented foods within an hour of onset.
📊
Sudden BP spike
Systolic often above 200. Onset over minutes, not hours. Often paired with bradycardia from baroreceptor reflex.
Same meal. Same gut. The only variable is whether monoamine oxidase is still working. Toggle to see what changes.
MAO degrades tyramine first-pass. NE stays parked. BP is boring.
Tyramine from food
Norepinephrine stored in vesicles
MAO in gut and liver (the gatekeeper)
NET uptake channel on the nerve terminal
Stage Four
The forbidden plate
High-tyramine foods. Tap each one to see why it lands on the no-list. The unifying theme is aging, curing, or fermentation: any bacterial decarboxylation of tyrosine cranks up tyramine content.
🧀
Aged cheese
cheddar, blue, brie
Cheese reaction
The original named trigger. Long aging means more bacterial tyrosine decarboxylation. Fresh mozzarella and cottage cheese are safer.
🥩
Cured meat
salami, soppressata, pepperoni
Aged protein
Bacterial breakdown of tyrosine during curing piles up tyramine. Fresh meat cooked the day it was bought is fine.
🍷
Soy sauce
tamari, fish sauce
Fermented condiment
Fermented soy is loaded. Sushi night with phenelzine is a trip to the ED.
🥣
Miso
soy paste, tempeh
Fermented soy
Same bacterial decarboxylation problem as soy sauce. Miso soup is not a free pass on an MAOI.
🍷
Red wine
chianti especially
Aged ferment
Chianti is the named offender. Tyramine content depends on aging and bacterial activity during fermentation.
🍺
Draft beer
tap beer, not bottled
Unpasteurized
Draft and unpasteurized beer keep live yeast working. Bottled pasteurized beer is much safer in small amounts.
🥫
Sauerkraut
kimchi, pickled cabbage
Lacto-fermented
Lactobacillus fermentation produces tyramine. Same logic for kimchi.
🍄
Fava beans
broad beans
L-dopa load
Fava beans carry levodopa and tyramine. Double trouble on an MAOI: extra catecholamine substrate plus the displacement engine.
Selegiline at low dose (10 mg/day or less) is MAO-B selective and does not strip the gut of MAO-A, so the dietary restriction is far looser. At higher doses selegiline loses selectivity and the diet rule comes back.
Stage Five
Treatment ladder
Goal is to drop BP fast without overshooting and without creating unopposed alpha vasoconstriction. Pick the rung that matches the physiology.
1
Phentolamine IV
Non-selective alpha blocker
The problem is alpha-1 vasoconstriction from a flood of NE. The fix is to directly block alpha-1. Phentolamine is short-acting and titratable. First-line and what the board wants.
2
Nitroprusside IV
Arterial and venous vasodilator (NO donor)
Acceptable if phentolamine is unavailable or if BP is refractory. Acts downstream of the receptor by relaxing vessel smooth muscle. Watch for cyanide toxicity on prolonged infusion and follow thiocyanate levels.
X
Beta-blocker monotherapy
Plain propranolol or metoprolol alone
Avoid. Beta-blockade without alpha-blockade leaves alpha-1 vasoconstriction unopposed; BP gets worse, not better. Same trap as pheochromocytoma. If you must use a beta blocker, only after alpha is already blocked, or use mixed alpha-beta blockade (labetalol) with caution.
Stage Six
The other MAOI trap
Tyramine crisis is not the only way to crash on these drugs. Serotonin syndrome is the other half of the MAOI safety story.
Serotonin syndrome alert
MAOI + serotonergic = ICU
An MAOI plus any of the agents below stacks serotonin to dangerous levels. Watch for the triad: autonomic instability (HTN, tachycardia, hyperthermia), neuromuscular hyperactivity (clonus, hyperreflexia, rigidity), and altered mental status.
SSRIfluoxetine, sertraline
SNRIvenlafaxine, duloxetine
Triptanssumatriptan
Opioidmeperidine, tramadol
Antibioticlinezolid
OTCdextromethorphan, St. John's wort
Two-week washout rule. Stop the MAOI for at least 14 days before starting any serotonergic drug, and the same when going the other direction. Fluoxetine needs 5 weeks because of its long half-life metabolite. Skip the washout and you can land a patient in the ICU.
Stage Seven
Choose before reveal
Do the bedside split first: tyramine crisis, serotonin syndrome, or allergic reaction.
A patient on phenelzine develops headache and diaphoresis 40 minutes after aged cheese. BP is 224/126, lungs are clear, skin has no urticaria, and neurologic exam shows no clonus. What lane is this?
Meal within an hour plus MAOI plus severe hypertension points to tyramine crisis. No urticaria or hypotension means not anaphylaxis. No clonus or hyperthermia means not serotonin syndrome.
Same patient, BP 230/132. Which pressure drug matches the receptor problem?
Alpha-1 vasoconstriction is the problem. Phentolamine blocks alpha receptors. Beta blocker alone can leave alpha-1 unopposed.
Visual check
Food triggers to recognize
These are pattern anchors, not diagnostic photos. Tap to enlarge.
Stage Eight
Lock it in
Five original vignettes. Read all five choices first, then hunt the stem for the clue.
0/5
Medically reviewed by Kaitlyn Cocuzzo, MD and Fatima Ali, DO · Last updated June 30, 2026 at 10:26 AM ET
Bone Wizardry is an independent educational resource for visual learning in the medical sciences. It is not affiliated with, endorsed by, or sponsored by any licensing or examination board, contains no real or recalled examination questions, and does not guarantee any educational or examination outcome.
