A 28-year-old woman with generalized anxiety disorder started on phenelzine 45 mg daily three weeks ago presents with severe occipital headache, neck stiffness, and diaphoresis. Vital signs reveal BP 220/140 mmHg, HR 128/min, RR 22/min, temperature 38.2°C. She reports consuming aged cheddar cheese and red wine approximately 30 minutes prior. Fundoscopic examination reveals bilateral flame hemorrhages. Serum creatinine is normal; urinalysis shows no proteinuria. Plasma metanephrines are markedly elevated. She denies recent SSRI use or sympathomimetic ingestion. What mechanism explains this hypertensive crisis?
- A)Enhanced metabolism of dietary monoamines
- B)Activation of peripheral nicotinic receptors
- C)Tyramine-induced massive catecholamine release from sympathetic terminalsGABARITO
- D)Competitive inhibition of dopamine reuptake
- E)Direct serotonin agonism at vascular smooth muscle
Explicação
MAOIs inhibit monoamine oxidase, which normally breaks down tyramine. Dietary tyramine from aged foods accumulates and acts as an indirect sympathomimetic, releasing massive amounts of norepinephrine from nerve terminals, causing hypertensive crisis. Ver explicação completa e trilha adaptativa →