Comparative Efficacy Study of Chewable Aspirin and Acetaminophen in the Antipyresis of Children

Aspirin and acetaminophen are the most widely used antipyretics in pediatrics. Most clinicians believe the drugs to be equally effective, though clinical opinion often suggests that aspirin is more effective at higher temperatures. Fifty-nine outpatients (age range, 2-8 years), presenting with rectal temperatures of 38.8 to 40.5 degrees C, were enrolled in this double-blind trial. The children were stratified by weight and initial temperature. One dose of chewable aspirin or acetaminophen (10-15 mg/kg based on current recommendations for weight) was administered, and rectal temperatures were monitored for three hours. Of the 59 patients enrolled, 46 successfully completed the protocol. Both drugs significantly reduced temperatures in the groups studied. Age did not influence the response of the children to the antipyretic effects of either drug. Aspirin and acetaminophen appeared equally effective when initial temperatures were between 38.8 and 39.9 degrees C. However, when the initial temperature was between 40.0 and 40.5 degrees C, the duration of effect of acetaminophen was shorter than that for aspirin. This suggests that therapeutic differences in the antipyretic activities of aspirin and acetaminophen may exist at higher temperatures.