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The information contained on this page is provided as general health information and is not intended to substitute as medical advice and direction from your physician or health care provider. Please direct any questions related to your health care provider. In an emergency, call 9-1-1 or go to the nearest emergency center.

Ulcer medications - histamine H2 antagonists


Histamine H2 antagonist ulcer medications include:

  • Cimetidine (Tagamet, Tagamet HB)
  • Famotidine (Pepcid, Pepcid AC, Heartburn Relief)
  • Nizatidine (Axid Oral Solution)
  • Ranitidine (Zantac, Taladine)

Histamine H2 antagonists may sometimes be combined with antacid. Such combination includes:

  • Famotidine/ calcium carbonate/ magnesium hydroxide (Pepcid Complete)


Taking histamine H2 antagonists may deplete vitamin B12.

Vitamin B12 (Cobalamin)

Low levels of vitamin B12 may cause any of the following symptoms:

  • Irritability
  • Weakness
  • Numbness
  • Anemia
  • Loss of appetite
  • Headache
  • Personality changes
  • Confusion

Low levels of vitamin B12 may increase the risk of heart diseases.

Editorial Note

The information presented here covers some of the nutrients that may be affected when you take certain medicines. If you have any of these signs and symptoms, it does not always mean you have low levels of these nutrients.

Factors that affect the level of nutrients are:

  • Your medical history
  • Diet
  • Lifestyle
  • How long you have been taking the medicine

Please talk to your health care provider. They can best address your health care needs and see if you are at risk for low levels of any nutrients.

Supporting Research

Dominiczak MH, Broom JI. Vitamins and minerals. In: Baynes JW, Dominiczak MH, eds. Medical Biochemistry. 4th ed. Philadelphia, PA: Elsevier Saunders; 2015:chap 11.

Gold Standard Drug Database. Drug Monograph: Calcium carbonate; Famotidine; Magnesium hydroxide, 2005.!/content/drug_monograph/6-s2.0-2588. Accessed July 19, 2016.

Gold Standard Drug Database. Drug Monograph: Cimetidine, 2016.!/content/drug_monograph/6-s2.0-126. Accessed July 5, 2016.

Gold Standard Drug Database. Drug Monograph: Famotidine, 2016.!/content/drug_monograph/6-s2.0-241. Accessed July 5, 2016.

Gold Standard Drug Database. Drug Monograph: Nizatidine, 2016.!/content/drug_monograph/6-s2.0-442. Accessed July 5, 2016.

Gold Standard Drug Database. Drug Monograph: Ranitidine, 2016.!/content/drug_monograph/6-s2.0-538. Accessed July 18, 2016.

National Institute of Health. Vitamin B12; Fact Sheet for Consumers. Updated June 24, 2011. Accessed July 8, 2016.

Sachdev HPS, Shah D. Vitamin B complex deficiencies and excess. In: Kliegman RM, Stanton BF, St Geme JW, Schor NF, eds. Nelson Textbook of Pediatrics. 20th ed. Philadelphia, PA: Elsevier; 2016:chap 49.

Shenkin A, Roberts NB. Vitamins and trace elements. In: Burtis CA, Ashwood ER, Bruns DE, eds. Tietz Textbook of Clinical Chemistry and Molecular Diagnostics. 5th ed. St Louis, MO: Elsevier Saunders; 2012:chap 31.