Comparison of the efficacy and safety of nonprescription doses of naproxen and naproxen sodium with ibuprofen, acetaminophen, and placebo in the treatment of primary dysmenorrhea: a pooled analysis of five studies.
Dysmenorrhea is the most common menstrual complaint in young women, with a prevalence as high as 90%. It is responsible for substantial repeated short-term absenteeism from school and work in young women. Effective treatments are available, including nonsteroidal anti-inflammatory drugs (NSAIDs). In many countries, a variety of NSAIDs have become available as over-the-counter (OTC) drugs.
                The goal of this study was to compare the efficacy and safety of OTC doses of naproxen (400 mg) and naproxen/naproxen sodium (200/220 mg) with acetaminophen (1000 mg), ibuprofen (200 mg), and placebo in the treatment of primary dysmenorrhea.
                A pooled analysis of 5 trials was performed. Efficacy was assessed by pain relief, relief of other dysmenorrheic symptoms, time to backup medication or remedication, and treatment preference. Tolerability was assessed by recording adverse events (AEs).
                A total of 443 women were enrolled in the combined studies. Naproxen 400 mg provided greater pain relief than acetaminophen and placebo within 30 minutes of administration (P < 0.01 and P < 0.05, respectively). Furthermore, naproxen 400 mg and 200 mg provided greater pain relief than both acetaminophen (P < 0.01 and P < 0.05, respectively) and ibuprofen (P < 0.001 and P < 0.01, respectively) at 6 hours after administration. Both doses of naproxen had higher scores than placebo for symptom relief and drug preference (all P < 0.001). The AEs and their frequency were similar among the treatment groups. No serious AEs were reported.
                When administered at OTC doses, naproxen was effective in the relief of pain and other symptoms of primary dysmenorrhea and had a good safety profile in the population studied.
There is inconclusive evidence to show whether or not NSAIDs (naproxen) are effective in managing pain caused by endometriosis. There is no evidence on whether any individual NSAID is more effective than another. As shown in other Cochrane reviews, women using NSAIDs need to be aware of the possibility that these drugs may cause unintended effects.