Famotidine is used to treat and prevent ulcers in the stomach and intestines. It also treats conditions in which the stomach produces too much acid, such as Zollinger-Ellison syndrome.
Headache, constipation, or diarrhea may occur. If any of these effects persist or worsen, tell your doctor or pharmacist promptly.
It is contraindicated in patients with known hypersensitivity to the drug.