Acetylcysteine: Timing Is Everything

AcetylcysteineWhich is more effective in preventing hepatotoxicity for patients with acute generic acetaminophen poisoning: 20-hour intravenous (IV) or 72-hour oral – acetylcysteine? According to a Canadian study, it’s important to know when the overdose occurred.

Of 2,086 patients in the 20-hour IV group, 13.9% experienced hepatotoxicity, compared with 15.8% among the 1,962 patients in the 72-hour oral group. The relative risk of hepatotoxicity was lower in the 20-hour IV group when the acetylcysteine was started within 12 hours of ingestion. The risk was lower in the 72-hour group when acetylcysteine was started later than 18 hours after ingestion. The researchers observed no significant difference in risk between the two groups when acetylcysteine treatment was started 12 to 18 hours after ingestion.

Source: Ann Emerg Med 2009;54:606-614