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Acetaminophen, the active ingredient in the popular over-the-counter analgesic Tylenol, has recently been found to have effects on psychological responses other than just reducing pain. Prior work in the laboratory has found that acetaminophen increases aggressive behavior on one laboratory measure of aggression, the Competitive Reaction Time task. The goal of this experiment was to further explore these social side effects and determine if the increase in aggressive behavior after taking acetaminophen generalizes to a different laboratory aggression paradigm, the Point Subtraction Aggression Paradigm (PSAP). The PSAP is a computer task in which participants engage in a competitive point-earning game with a fictitious opponent. Participants (N = 106) received 1000mg of acetaminophen or placebo and one hour later completed a 10-minute session of the PSAP. There was no effect of acetaminophen on aggressive responding. However, the acetaminophen group had marginally significant reductions in aggressive motivations and emotions. Participants receiving acetaminophen also accurately perceived the number of points subtracted from them by their opponent (i.e. provocations), whereas the placebo group underestimated the number. Thus, the increase in aggressive behavior seen on the CRT does not appear to generalize to the PSAP. The reductions in aggressive emotions and motivations for those in the acetaminophen condition on the PSAP suggest that drug effects may vary by the situation. This work is important in understanding the psychological side effects of a drug that is used by many people on a regular basis.