What medication is used as prophylaxis against NSAID-induced ulcers?

Misoprostol is the medication that is specifically indicated for prophylaxis against NSAID-induced ulcers. It is a synthetic prostaglandin E1 analog that works by increasing the production of gastric mucus, enhancing bicarbonate secretion, and promoting mucosal blood flow. These mechanisms help protect the gastric lining from the damaging effects of nonsteroidal anti-inflammatory drugs (NSAIDs), which can lead to ulcers and gastrointestinal bleeding due to their inhibition of prostaglandin synthesis.

While famotidine and omeprazole are effective in managing acid-related conditions, they do not provide the protective mucosal effects needed to prevent NSAID-induced ulcers. Famotidine is an H2 receptor antagonist that reduces gastric acid secretion, and omeprazole is a proton pump inhibitor that provides more prolonged suppression of gastric acid production. Both may help in treating ulcers but are not primarily used for prophylaxis against NSAID-induced ulcers.

Diphenhydramine, an antihistamine primarily used for allergic reactions, does not play a role in ulcer prophylaxis and is unrelated to gastric protection from NSAIDs. Therefore, misoprostol's unique properties in healing and protecting the gastric mucosa make it the appropriate choice for this specific indication.