Famotidine

Famotidine (brand name Pepcid) is an H2 blocker that reduces stomach acid, used for conditions like GERD, ulcers, and heartburn, available OTC and by prescription. It works by blocking histamine receptors on stomach cells, decreasing acid production, with common side effects including headache, constipation, and diarrhea, but serious ones are rare. Always consult a doctor for proper use, especially with other medications or persistent symptoms