Effect of Therapeutic Doses of Acetaminophen (up to 4 g/day) on Serum Alanine Aminotransferase Levels in Subjects Consuming Ethanol: Systematic Review and Meta-analysis of Randomized Controlled Trials

Study Objective. To quantify the effect of therapeutic doses of acetaminophen on serum alanine aminotransferase (ALT) levels in subjects who consumed ethanol. Design. Systematic review of six randomized placebo-controlled trials, of which five were included in a meta-analysis. Subjects. Subjects included in the meta-analysis were those who consumed ethanol and received acetaminophen in doses up to 4 g/day (551 subjects) or placebo (350 subjects). Measurements and Main Results. A comprehensive literature search of the MEDLINE, EMBASE, and International Pharmaceutical Abstracts databases and the Cochrane Central Register of Controlled Trials was performed to identify randomized, placebo-controlled trials that enrolled subjects who consumed ethanol, received acetaminophen in therapeutic doses up to 4 g/day, and had serum ALT level measurements. A total of 184 articles were identified; six articles met all criteria. Five of the six articles reported ALT levels on study day 4 for both groups of subjects who received acetaminophen or placebo. Thus, for the meta-analysis, we used the primary outcome of mean change in serum ALT level from baseline to day 4 in the acetaminophen groups compared with the placebo groups. We found that the difference in mean change from baseline ALT levels between the acetaminophen and placebo groups on day 4 was 0.0 U/L (95% confidence interval -0.2-0.1 U/L). There were no reports of liver dysfunction, liver failure, or death in any of the trials. Conclusion. In randomized, placebo-controlled trials of subjects who consumed ethanol, no elevation of ALT level on study day 4 was noted when subjects ingested up to 4 g/day of acetaminophen.