Misoprostol is a synthetic analogue of a natural prostaglandin E1, used in the treatment and prevention of stomach ulcers, sometimes administered concomitantly with NSAIDs to prevent the formation of duodenal/gastric ulcers. It is also used to induce abortion, and for post-partum hemorrhage. It is believed to induce the mucous membranes lining the gastrointestinal [GI] tract to secrete more mucous and mucosal blood flow, while acting on the parietal cells to limit the production of pepsin in the gastric juices, increasing the thickness of the mucosal layer, and stabilizing the tissues, which protects the GI tract and prevents the formation of ulcers.