Intravenous acetylcysteine for the treatment of acetaminophen overdose.

IMPORTANCE OF THE FIELD: Acetaminophen is a leading cause of overdose-related hepatotoxicity. Although acetylcysteine prevents or minimizes acetaminophen-induced hepatotoxicity and reduces mortality, some patients presenting with complicated overdose scenarios (massive ingestions or combination or modified-release formulations) may develop toxicity despite administration of recommended dosage regimen. AREAS COVERED IN THIS REVIEW: The article evaluates evidence regarding intravenous acetylcysteine's effectiveness in patients with acute overdoses who receive treatment within 10 h or > 10 h, patients with chronic supratherapeutic ingestions, and those with acetaminophen-induced fulminant hepatic failure. Intravenous and oral acetylcysteine are compared. WHAT THE READER WILL GAIN: A one-size-fits-all approach towards acetylcysteine therapy provides suboptimal care in some patients. High-risk patients are identified. Specific discontinuation criteria are presented. TAKE HOME MESSAGE: The standard intravenous regimen will effectively treat most early-presenting uncomplicated overdoses. Acetylcysteine dosing should be individualized in patients with complicated presentations and in particular situations in which plasma acetaminophen concentrations may be persistently elevated at the end of the infusion or in late presenters. More studies are needed to evaluate the optimal intravenous dosage regimen and the role of oral acetylcysteine in these high-risk patients. Treatment decisions may be aided by consultation with a poison center and/or clinical toxicologist.