Practice Patterns for N-acetylcysteine Dosing for Acetaminophen Toxicity in the United States

Background: Although the FDA approved acetaminophen toxicity dosing regimen for intravenous n-acetylcysteine (NAC) is a three-bag regimen, alternate regimens have been published which are generally simpler, and decrease errors and adverse effects. It is not clear how pervasive alternative regimens are used in hospitals in the US and reasons for a change from the FDA regimen. Objective: Characterize practice patterns for treating acetaminophen toxicity. Methods: A pilot-tested, electronic survey containing demographic and practice pattern questions for acetaminophen toxicity management was sent to residency program directors. The survey was open for 4 weeks with several reminder e-mails sent to non-responders. Descriptive statistics were used to summarize the data. Results: There were 119 responses (9.2% response rate). Responses were representative of all geographic areas in the US and were most commonly from community hospitals (67.2%) and those with 300 or more beds (72.2%). Nearly two-thirds used the FDA approved NAC regimen, whereas others used an alternate regimen. Reasons for making the change were for simplicity, to decrease errors or adverse events, or based on local poison center recommendations. More than one-third of respondents reported not using a maximum dosing weight. Conclusions: N-acetylcysteine is usually administered intravenously using the FDA approved regimen for acetaminophen toxicity. The weight for dosing was commonly capped at 100 kg, but some institutions did not use a maximum. Alternative intravenous regimens have been implemented at some institutions with the impetus for change being safety and simplicity.