Highlights & Basics
- Acetaminophen overdose may occur after an acute single ingestion of a large amount of acetaminophen or acetaminophen-containing medication, or repeated ingestion of an amount exceeding recommended dosage.
- Patients are often asymptomatic or have only mild gastrointestinal symptoms at initial presentation. Untreated acetaminophen poisoning may cause varying degrees of liver injury over the 1 to 4 days following ingestion, including fulminant hepatic failure.
- Rarely, massive overdose may initially present with coma and severe metabolic acidosis. Presentation with coma may also occur if a combination preparation of acetaminophen and opioid is taken in overdose, or after an overdose of multiple drugs.
- Hepatotoxicity is extremely rare in patients treated with acetylcysteine within 8 hours of an acute acetaminophen overdose. The efficacy of acetylcysteine decreases subsequent to the first 8 hours following an acute acetaminophen overdose, with a corresponding stepwise increase in hepatotoxicity with increasing treatment delays beyond 8 hours.
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Definition
Epidemiology
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Citations
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American College of Medical Toxicology. ACMT Position statement: duration of intravenous acetylcysteine therapy following acetaminophen overdose. J Med Toxicol. 2017 Mar;13(1):126-7.[Abstract][Full Text]
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