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H2 blockers

Peptic ulcer disease - H2 blockers; PUD - H2 blockers; Gastroesophageal reflux - H2 blockers; GERD - H2 blockers

H2 blockers are medicines that work by reducing the amount of stomach acid secreted by glands in the lining of your stomach.

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How H2 Blockers Help you

H2 blockers are used to:

Types of H2 Blockers

There are different names and brands of H2 blockers. All are available over the counter without a prescription. Most work equally as well. Side effects may vary from drug to drug.

Taking Your H2 Blockers

H2 blockers are most often taken by mouth. You can get them in the form of tablets, liquids, or capsules.

H2 blockers may be bought in lower doses at the store without a prescription. If you find yourself taking these most days for 2 weeks or more for acid reflux symptoms, make sure you see your health care provider about your symptoms.

If you have a peptic ulcer, your provider may prescribe H2 blockers along with 2 or 3 other medicines for up to 2 weeks.

If your provider prescribed these medicines for you:

Side Effects

Side effects from H2 blockers are rare.

If you are breastfeeding or pregnant, talk to your provider before taking these medicines. If you have kidney problems, do not use famotidine without talking to your provider.

Tell your provider about other medicines you are taking. H2 blockers may change the way certain drugs work. This problem is less likely with cimetidine and nizatidine.

When to Call the Doctor

Call your provider if:

References

Katz PO, Gerson LB, Vela MF. Guidelines for the diagnosis and management of gastroesophageal reflux disease. Am J Gastroenterol. 2013;108(3):308-328. PMID: 23419381 pubmed.ncbi.nlm.nih.gov/23419381/.

Richter JE, Vaezi MF. Gastroesophageal reflux disease. In: Feldman M, Friedman LS, Brandt LJ, eds. Sleisenger and Fordtran's Gastrointestinal and Liver Disease. 11th ed. Philadelphia, PA: Elsevier; 2021:chap 46.

Waller DG. Dyspepsia, peptic ulcer disease, and gastrooesophageal reflux disease. In: Waller DG, Sampson A, Hitchings A, eds. Medical Pharmacology and Therapeutics. 6th ed. Philadelphia, PA: Elsevier; 2022:chap 33.

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Review Date: 4/22/2021  

Reviewed By: Michael M. Phillips, MD, Emeritus Professor of Medicine, The George Washington University School of Medicine, Washington, DC. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team. Editorial update 11/29/2021.

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