Disturbance of menstruation as a side‐effect of nonsteroidal anti‐inflammatory drugs (NSAIDs)

Menstrual disturbances are not a generally recognized side‐effect of non‐steroidal antiinflammatory drugs (NSAIDs). Five case reports to the Netherlands Pharmacovigilance Foundation LAREB concern menstrual disturbances in suspected connection with the use of an NSAID. In one patient at several occasions the use of naproxen for dysmenorrhoea was followed by interruption of menstruation. In four other women the use of diclofenac, indomethacin or naproxen was followed by hypo‐ or amenorrhoea of one cycle duration. Prostaglandins play a complex role in the physiology of menstruation. The effects of NSAIDs on cyclo‐oxygenase and prostaglandin metabolism may explain the observed disturbances of menstruation. Female patients of child‐bearing age using an NSAID — either to treat dysmenorrhea or for other reasons — should be aware of the possibility of interruption, delay, decrease or missing of a menstrual period.