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Patient handout

MAOI–tyramine hypertensive crisis ("cheese effect" — severe occipital headache + HTN crisis + tachycardia + diaphoresis after MAOI + tyramine-rich food or sympathomimetic exposure)

PRODUCTION

1. Your condition

This handout is for maoi–tyramine hypertensive crisis ("cheese effect" — severe occipital headache + htn crisis + tachycardia + diaphoresis after maoi + tyramine-rich food or sympathomimetic exposure). Your care team identified this based on: irreversible maoi (phenelzine, tranylcypromine, isocarboxazid, selegiline transdermal high-dose) + tyramine-rich food (aged cheese, cured meats, fava beans, soy sauce, draft beer, fermented foods) or sympathomimetic medication (decongestant, ephedra, otc cold med) within 30 min – 2 h (wimbiscus cleve clin j med 2010 pmid 21048054; shulman j clin psychiatry 2003 pmid 14728101).

Other reasons your team may use this plan: severe occipital headache + sbp ≥180/dbp ≥120 + diaphoresis + tachycardia + photophobia within 30 min – 2 h of maoi + tyramine/sympathomimetic exposure — classic "cheese reaction"; patient on irreversible maoi receiving meperidine, ssri, snri, tramadol, or dextromethorphan — drug-drug interaction with potential for tyramine-like surge or serotonin syndrome overlap.

2. Your medications

Take these medications exactly as prescribed. Do not stop or change a dose without talking to your provider.

MedicationStarting doseHowWhenWhat it does
phentolamine5 mg IV bolus q5-15 min titrate to SBP <160; typical total 5-20 mg cumulative; can give 1-5 mg increments for fine titrationIVPRN bolus titratedWimbiscus Cleve Clin J Med 2010 PMID 21048054 + Fiedorowicz 2004 PMID 15330418 — phentolamine cornerstone for tyramine crisis (reverses NE surge); same drug used for pheochromocytoma crisis (analogous catecholamine-excess physiology)
nicardipine5 mg/h IV titrate q5 min by 2.5 mg/h to max 15 mg/hIVcontinuousAHA 2025 HTN guideline + ACC 2017 — preferred IV agent if phentolamine unavailable; titratable + autoregulation-aware; safe in MAOI patients
labetalolUse ONLY AFTER alpha-blockade established with phentolamine; 10-20 mg IV q10 min, max 300 mgIVPRN bolusAHA 2025 HTN — mixed alpha-beta acceptable AFTER phentolamine controls alpha component (analogous to pheochromocytoma sequencing); tiny beta component initially raises unopposed alpha concern but practical use ok with simultaneous phentolamine
esmololUse ONLY AFTER alpha-blockade with phentolamine; 500 mcg/kg IV bolus then 50-200 mcg/kg/min infusion titrateIVcontinuous infusionShort half-life beta-blocker for HR control AFTER alpha-blockade; same logic as pheochromocytoma
acetaminophen650-1000 mg PO/IV q6hPO/IVq6h PRNNon-opioid headache control; first-line analgesic in MAOI patients (avoids meperidine + tramadol risks)
AVOID meperidineAVOIDN/AN/AFDA boxed warning — meperidine + MAOI = severe hyperthermic + hypertensive + serotonergic reactions; absolute contraindication
AVOID β-blocker monotherapyAVOID monotherapyN/AN/AUnopposed alpha vasoconstriction (analogous to pheochromocytoma + cocaine teaching); β-blocker only AFTER phentolamine alpha-blockade established
AVOID sympathomimetics (pseudoephedrine, phenylephrine, ephedra, OTC cold meds)AVOIDN/Along-term while on MAOISympathomimetics + MAOI = recurrent tyramine-like crises; lifetime avoidance + medication card education
AVOID SSRI/SNRI/tramadol/dextromethorphan during MAOI + 14-d washoutAVOID without 14-d washoutN/Along-termSerotonin syndrome risk; mandatory 14-d washout before/after irreversible MAOI; for fluoxetine require 5-wk washout (long half-life)
AVOID nitroprussideAVOID prolonged useN/AN/ACyanide accumulation with prolonged infusion; nicardipine preferred

Plan: MAOI–tyramine HTN crisis — phentolamine IV cornerstone (alpha-blocker) + nicardipine alternative; AVOID β-blocker monotherapy (unopposed alpha); AVOID meperidine (FDA boxed warning in MAOI); strict tyramine diet + sympathomimetic-medication-avoidance education

3. When to call your provider

Contact your care team if any of the following happen:

  • Recurrent tyramine crisis → ED + flag offending agent + reinforce education
  • BP rebound → urgent visit
  • New depression/SI → emergent psychiatry
  • New prescription needing interaction check → pharmacy MTM

4. When to seek emergency care

Call 911 or go to the nearest emergency room right away if you have:

  • New focal neurologic deficit OR sudden severe headache with declining mental status in MAOI-tyramine crisis — ICH (case-reported fatal complication of cheese reactions per Wimbiscus 2010)(life-threatening)
  • Severe back/chest pain + BP differential between arms or pulse deficit in MAOI-tyramine crisis — dissection from severe HTN (severe HTN is dissection risk factor)(life-threatening)
  • New meperidine, SSRI, SNRI, tramadol, or dextromethorphan ordered for MAOI patient during admission — interaction missed during med-rec — high risk for serotonin syndrome OR hypertensive crisis (FDA boxed warning for meperidine)
  • β-blocker monotherapy administered in MAOI-tyramine crisis — unopposed alpha vasoconstriction worsens HTN (analogous to pheochromocytoma + cocaine)

5. Follow-up

COMPREHENSIVE TYRAMINE-RESTRICTED DIET EDUCATION (handout + dietitian consult; high-tyramine foods to AVOID: aged cheeses, cured meats, fava beans, soy sauce, draft beer, sauerkraut, fermented soy, miso, tempeh, marmite/vegemite, tap beer; safe-in-moderation: pasteurized cheese, fresh meat, processed cheese); MEDICATION INTERACTION LIST education (AVOID sympathomimetics — pseudoephedrine, phenylephrine, ephedra, OTC cold meds, decongestants; AVOID meperidine — FDA boxed warning; AVOID SSRI/SNRI/tramadol/dextromethorphan during MAOI + 14-d washout); psychiatry consultation re: continuing MAOI vs alternative (consider switch to MAOI-B selective transdermal selegiline if low-dose tolerated, OR switch to other antidepressant class with appropriate washout); if MAOI required to continue, dietitian referral + medication card carried + family education + MedicAlert bracelet; outpatient PCP + psychiatry follow-up within 1-2 weeks

6. Sources

Guideline: Wimbiscus Cleve Clin J Med 2010 (PMID 21048054) — MAOI safety + tyramine reactions + drug interactions; 2025 ACC/AHA HTN (Whelton); FDA boxed warning meperidine + MAOI

  1. pubmed.ncbi.nlm.nih.gov/21048054
  2. pubmed.ncbi.nlm.nih.gov/14728101
  3. pubmed.ncbi.nlm.nih.gov/15330418