How it works

Famotidine treats some gastrointestinal diseases characterized by high acid production by reducing the quantity of stomach acid produced.

By blocking the action of histamine on histamine H2-receptors found on the parietal cells lining the stomach wall, famotidine lowers the release of gastric acid in the stomach. The chemical transmitter called histamine causes the parietal cells to secrete stomach acid. Famotidine prevents histamine from having this impact by inhibiting H2 receptors, which lowers gastric acid output.

Famotidine targets just H2 receptors (other drugs, called antihistamines, block H1 receptors that are primarily involved with allergic-type reactions).

Famotidine is a member of the class of medications known as H2 receptor antagonists (also called H2 blockers).