Misoprostol (59122-46-2)

The most commonly reported adverse effect of taking a Misoprostol (CAS NO.59122-46-2) 200 μg tablet by mouth four times a day to reduce the risk of NSAID-induced gastric ulcers is diarrhea. In clinical trials, an average 13% of patients reported diarrhea, which was dose-related and usually developed early in the course of therapy (after 13 days) and was usually self-limiting (often resolving within 8 days), but sometimes (in 2% of patients) required discontinuation of misoprostol.
The next most commonly reported adverse effects of taking a misoprostol 200 μg tablet by mouth four times a day to reduce the risk of NSAID-induced gastric ulcers are: abdominal pain, nausea, flatulence, headache, dyspepsia, vomiting, and constipation, but none of these adverse effects occurred significantly more often than when taking placebos.
Misoprostol should not be taken by pregnant women to reduce the risk of NSAID-induced gastric ulcers because it increases uterine tone and contractions in pregnancy which may cause partial or complete abortions, and because its use in pregnancy has been associated with birth defects.
A study published in the Journal of Immunology (June 15, 2008 online) suggests that the immunosuppressive effect of misoprostol, if given vaginally rather than orally along with RU-486 to terminate a pregnancy, is likely the reason a small number of women taking the two-drug combination have contracted a fatal bacterial infection.In animal and cell culture studies, the researchers found that misoprostol, when given directly in the reproductive tract (vaginally), suppresses key immune responses and can allow a normally non-threatening bacterium, Clostridium sordellii, to gain the upper hand and cause deadly infection. When absorbed through the stomach (orally), however, the drug did not compromise immune defenses or cause illness.