A new meta-analysis of previous research on acetaminophen (also known as paracetamol outside the U.S.) vs. NSAIDs (nonsteroidal anti-inflammatory drugs) for treatment of menstrual pain indicates that NSAIDs are more effective. NSAIDs include aspirin, ibuprofen, and naproxen sodium, which are all readily available over-the-counter in the U.S. The research pooled results from 73 randomized controlled trials comparing the effectiveness and safety of NSAIDs vs. placebo, vs. acetaminophen, and each other.
The results don’t indicate whether one NSAID is any better than any other for menstrual pain. Researcher Jane Marjoribanks, M.D., Cochrane Menstrual Disorders and Subfertility Group in Auckland, New Zealand, says they work by reducing prostaglandins, the substance manufactured by the uterine lining to help the uterus contract and expel menstrual fluid.
“Research has shown that women with dysmenorrhoea have high levels of prostaglandins, hormones known to cause cramping abdominal pain. …NSAIDs are drugs which act by blocking prostaglandin production.”