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What are H2 blockers?

Donna Hill Howes, RN
Family Practitioner

Histamine receptor blockers (H2 blockers) are drugs that interact with a receptor in the stomach to reduce stomach acid. H2 blockers include cimetidine (Tagamet), famotidine (Pepcid), nizatidine (Axid), and ranitidine (Zantac). They are all available over the counter in the US, but at lower dosages than prescription strength.

Talk to a doctor before taking an over-the-counter H2 blocker for longer than recommended. People with long-term heartburn are at risk for complications of acid reflux. They may also have other conditions not yet diagnosed.

This answer was adapted from Sharecare's award-winning AskMD app. Start a consultation now to find out what's causing your symptoms, learn how to manage a condition, or find a doctor.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.