Efficacy and safety of acetaminophen in the treatment of migraine - Results of a randomized, double-blind, placebo-controlled, population-based study

Background: Although most persons with migraine treat their headaches with over-the-counter medication, systematic data on the safety and efficacy of widely used treatment, including acetaminophen, are sparse. Methods: This is a randomized, double-blind, placebo-controlled study compa ring oral acetaminophen, 1000 mg (two 500-mg Extra Strength Tylenol tablets ), with identical placebo in the treatment of a single acute migraine attac k. Eligible subjects met International Headache Society diagnostic criteria for migraine with or without aura. Patients who usually required bed rest with their headaches or who vomited more than 20% of the time were excluded . Main Outcome Measures: The percentage of subjects who, at 2 hours after dos ing, experienced a change in baseline pain intensity from severe or moderat e pain to mild or no pain (headache response); and pain intensity differenc e from baseline at the 2-hour postmedication assessment. Results: The headache response rate 2 hours after dosing was 57.8% in the a cetaminophen group and 38.7% in the placebo group (P = .002). Pain-free rat es at 2 hours were 22.4% in the acetaminophen group and 11.3% in the placeb o group (P = .01). The mean pain intensity difference from baseline 2 hours after dosing was 1.08 in the acetaminophen group and 0.73 in the placebo g roup (P<.001). At 2 hours, other migraine headache characteristics, such as functional disability (P=.002), photophobia (P=.02), and phonophobia (P=.0 8), were significantly improved after treatment with acetaminophen vs place bo. Conclusions: Acetaminophen was highly effective for treating pain, function al disability, photophobia, and phonophobia in a population-based sample of persons with migraine, excluding the most disabled persons with migraine. The drug also had an excellent safety profile and was well tolerated.