Sections View Full Chapter Figures Tables Videos Annotate Full Chapter Figures Tables Videos Supplementary Content + Download Section PDF Listen ++ For further information, see CMDT Part 38-46: Monoamine Oxidase Inhibitors Overdose + Key Features Download Section PDF Listen +++ ++ Potential food or drug interactions can occur during therapeutic use Ingestion of tyramine-containing foods (eg, aged cheese and red wines) or any sympathomimetic drug may cause a severe hypertensive reaction Severe or fatal hyperthermia (serotonin syndrome) May occur when monoamine oxidase inhibitors (MAOIs) are given with serotonin-enhancing drugs (eg, meperidine, fluoxetine, paroxetine, fluvoxamine, venlafaxine, tryptophan, dextromethorphan, tramadol) Can also occur with moclobemide (an MAOI not available in the United States) and linezolid, which has MAOI properties Can also occur with selective serotonin reuptake inhibitors (SSRIs) in large doses or in combination with other SSRIs, even in the absence of an MAOI or meperidine + Clinical Findings Download Section PDF Listen +++ ++ Acute overdose Ataxia, excitement, hypertension, and tachycardia Several hours later: hypotension, convulsions, and hyperthermia Food or drug hypertensive reaction Hypertension Tachycardia Headache Possible intracranial hemorrhage Serotonin syndrome Fever Agitation Delirium Diaphoresis Hyperreflexia Clonus (spontaneous, inducible, ocular) Hyperthermia (can be life-threatening) + Diagnosis Download Section PDF Listen +++ ++ Serum drug levels are not available nor useful Generally not detected on urine toxicology screens + Treatment Download Section PDF Listen +++ ++ Acute overdose Administer activated charcoal, 60–100 g orally or via gastric tube, mixed in aqueous slurry if ingestion is within 1 Treat hypotension with fluids and positioning, but avoid use of pressor agents if possible Treat severe hypertension with nitroprusside, phentolamine, or other rapid-acting vasodilators Serotonin syndrome Cyproheptadine, 4 mg orally (or by gastric tube) every hour for three or four doses, or chlorpromazine 25 mg intravenously, can be effective Observe patients for at least 24 h because hyperthermia may be delayed (see Hyperthermia)