In this factorial study, 148 outpatients with pain after oral surgery were randomly assigned, on a double-blind basis, a single oral dose of acetaminophen 650 mg, phenyltoloxamine 60 mg, a combination of acetaminophen 650 mg with phenyltoloxamine 60 mg, or placebo. Using a self-rating record, subjects rated their pain and its relief hourly for 6 hours after medication. Measures of total and peak analgesia were derived from these subjective reports. The acetaminophen effect was significant for every measure of total and peak analgesia. The phenyltoloxamine effect was not significant for any measure of analgesia. Although efficacy was lower for the acetaminophen-phenyltoloxamine combination than for acetaminophen alone, for every variable, the contrast for interaction was not statistically significant. The results of this study differ from those of previous studies in patients with headache and musculoskeletal pain. All adverse effects were transitory and consistent with the known pharmacologic profiles of the study medications or the backup analgesic.