Background and Objectives Preventive analgesia has been proposed as a potential strategy to reduce postoperative pain. However, there is currently no review that focuses on acetaminophen for preventive analgesia.

Methods We conducted a search of MEDLINE, EMBASE, Cinahl, AMED, and CENTRAL databases identifying randomized controlled trials that compared preventive acetaminophen with postincision acetaminophen.

Results Seven studies with 544 participants were included. Overall, the studies showed a reduction in 24-hour opioid consumption (standardized mean difference [SMD] of −0.52; 95% confidence interval [95% CI], −0.98 to −0.06), lower pain scores at 1 hour (MD, −0.50; 95% CI, −0.98 to −0.02) and 2 hours (MD, −0.34; 95% CI, −0.67 to −0.01), and a lower incidence of postoperative vomiting (risk ratio, 0.50; 95% CI, 0.31–0.83) in the preventive acetaminophen group. Current studies are limited by a potential risk of bias.

Conclusions To our knowledge, this is the first review to describe a potential preventive effect of acetaminophen. However, well-conducted randomized controlled trials are necessary to substantiate the conclusions of this review.