Efficacy of fenoprofen in the treatment of primary dysmenorrhea.

We compared fenoprofen calcium, 200 mg; fenoprofen calcium, 400 mg; aspirin, 650 mg; and a placebo in 85 women for the relief of primary dysmenorrhea in a double-blind, clinical trial. The usefulness of these drugs was judged from data obtained over four consecutive menstrual periods on: restriction of daily activity, pain intensity scores, need for rescue analgesics, withdrawal due to lack of efficacy, and adverse events. Both fenoprofen, 200 mg, and fenoprofen, 400 mg, offered significant (P less than .01) pain relief when compared to placebo and aspirin. Analyses of data on 1, 2 and 3 indicated that aspirin was not significantly different from placebo. The aspirin-treated group reported the greatest number of adverse reactions, but the differences between the four groups were not statistically significant. Our study lends support to the concept of a "plateau analgesic effect" of nonsteroidal antiinflammatory drugs (NSAIDs): fenoprofen, 200 mg, appears to be as effective as fenoprofen, 400 mg. When this type of drug fails to provide relief for a woman suffering from primary dysmenorrhea, switching to another NSAID may be more appropriate than increasing the dosage and the probability of dosage-related side effects.