Misoprostol reduces stomach acid and helps protect the stomach from damage that can be caused by taking a nonsteroidal anti-inflammatory drug (NSAID) such as aspirin, ibuprofen (Advil, Motrin), naproxen (Aleve), celecoxib, diclofenac, indomethacin, meloxicam, and others. Misoprostol is used to prevent stomach ulcers during treatment with aspirin or an NSAID. Misoprostol can cause birth defects, premature birth, uterine rupture, miscarriage, or incomplete miscarriage and dangerous uterine bleeding. Do not use misoprostol if you are pregnant. If you are able to become pregnant, you will need to have a negative pregnancy test before starting this treatment. You will also need to use effective birth control to prevent pregnancy during treatment.