Comparison of 650 mg aspirin and 1,000 mg acetaminophen with each other, and with placebo in moderately severe headache.

Two-hundred-sixty-nine otherwise healthy persons experiencing periodic, moderately severe headache of a type that had previously responded to nonprescription medications completed this randomized, parallel, double-blind study. The three demographically similar subgroups took either 1,000 mg acetaminophen, 650 mg aspirin, or an identical placebo, for headache. Headache intensity and relief scores over the following six hours were obtained and assessed by sums of pain intensity difference and values of pain relief scores analyses. Responses for the group, and for the subgroup with tension headaches (107 persons) showed no differences between the effects of the active medications. The effects of each medication were strongly superior to placebo. There were no differences in side effects among the three treatment modalities. In persons experiencing tension-vascular headaches (162), only aspirin, at two hours, was superior to placebo, but direct comparison with acetaminophen suggested no real difference. Acetaminophen (1,000 mg) and aspirin (650 mg) are clinically similar in treating the headaches for which they are commonly taken. Recommendations for their use in treating headache should be based on individual patient suitability and on cost factors.