A multicenter comparison of the safety of oral versus intravenous acetylcysteine for treatment of acetaminophen overdose

Clin Toxicol (Phila). 2010 Jun;48(5):424-30. doi: 10.3109/15563650.2010.486381.


Oral and intravenous (IV) N-acetylcysteine (NAC) are used for the treatment of acetaminophen poisoning. The objective of this multicenter study was to compare the safety of these two routes of administration.

Methods: We conducted a multicenter chart review of all patients treated with NAC for acetaminophen poisoning. The primary safety outcome was the percentage of patients with NAC-related adverse events.

Results: A total of 503 subjects were included in the safety analysis (306 IV-only, 145 oral-only, and 52 both routes). There were no serious adverse events related to NAC for either route. Nausea and vomiting were the most common related adverse events and were more common with oral treatment (23 vs. 9%). Anaphylactoid reactions were more common with IV administration (6 vs. 2%).

Conclusions: IV and oral NAC are generally mild adverse drug reactions.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acetaminophen / poisoning*
  • Acetylcysteine / administration & dosage*
  • Acetylcysteine / poisoning
  • Acetylcysteine / therapeutic use*
  • Anaphylaxis / chemically induced
  • Drug Administration Routes
  • Drug Overdose / drug therapy
  • Humans
  • Infusions, Intravenous
  • Injections, Intravenous
  • Nausea / chemically induced
  • Nausea / drug therapy
  • Safety
  • Treatment Outcome
  • Vomiting / chemically induced
  • Vomiting / drug therapy


  • Acetaminophen
  • Acetylcysteine