Drug

Famotidine

Common brand names:

Pepcid, Pepcid AC

Famotidine is a member of the H-2 blocker (histamine blocker) family of drugs that prevents the release of acid into the stomach. Famotidine is used to treat stomach and duodenal ulcers, reflux of stomach acid into the esophagus, and Zollinger-Ellison syndrome. Famotidine is available as a prescription drug and as a nonprescription product for relief of heartburn, acid indigestion, and sour stomach.

Summary of Interactions with Vitamins, Herbs, & Foods

  • Negative Interactions

    1
    • Famotidine

      Magnesium

      Reduces Effectiveness

      In healthy people, a magnesium hydroxide/aluminum hydroxide antacid, taken with famotidine, decreased famotidine absorption by 20–25%. People can avoid this interaction by taking famotidine two hours before or after any aluminum/magnesium-containing antacids. Some magnesium supplements such as magnesium hydroxide are also antacids.

      Magnesium
      Famotidine
      ×
      1. Bachmann KA, Sullivan TJ, Jauregui L, et al. Drug interactions of H2-receptor antagonists. Scand J Gastroenterol Suppl 1994;206:14-9.
  • Supportive Interactions

    5
    • Famotidine

      Beta-Carotene

      Replenish Depleted Nutrients

      This interaction is based on this drug belonging to a drug class. While this drug may differ from the text and references below, drugs within this class work in a similar way and this interaction is applicable to drugs within the same class.

      Omeprazole, a drug closely related to lansoprazole, taken for seven days led to a near-total loss of stomach acid in healthy people and interfered with the absorption of a single administration of 120 mg of beta-carotene. It is unknown whether repeated administration of beta-carotene would overcome this problem or if absorption of carotenoids from food would be impaired. Persons taking omeprazole and related acid-blocking drugs for long periods may want to have carotenoid blood levels checked, eat plenty of fruits and vegetables, and consider supplementing with carotenoids.

      Beta-Carotene
      Famotidine
      ×
      1. Tang G, Serfaty-Lacronsniere C, Camilo ME, Russell RM. Gastric acidity influences the blood response to a beta-carotene dose in humans. Am J Clin Nutr 1996;64:622-6.
    • Famotidine

      Copper

      Replenish Depleted Nutrients

      Some evidence indicates that other vitamins and minerals, such as folic acid and copper, require the presence of stomach acid for optimal absorption. Long-term use of H-2 blockers may therefore promote a deficiency of these nutrients. Individuals requiring long-term use of H-2 blockers may therefore benefit from a multiple vitamin/mineral supplement.

      Copper
      Famotidine
      ×
      1. Russell RM, Krasinski SD, Samloff IM. Correction of impaired folic acid (Pte Glu) absorption by orally administered HCl in subjects with gastric atrophy. Am J Clin Nutr 1984;39:656.
      2. Tompsett SL. Factors influencing the absorption of iron and copper from the alimentary tract. Biochem J 1940;34:961-9.
    • Famotidine

      Folic Acid

      Replenish Depleted Nutrients

      Some evidence indicates that other vitamins and minerals, such as folic acid and copper, require the presence of stomach acid for optimal absorption. Long-term use of H-2 blockers may therefore promote a deficiency of these nutrients. Individuals requiring long-term use of H-2 blockers may therefore benefit from a multiple vitamin/mineral supplement.

      Folic Acid
      Famotidine
      ×
      1. Russell RM, Krasinski SD, Samloff IM. Correction of impaired folic acid (Pte Glu) absorption by orally administered HCl in subjects with gastric atrophy. Am J Clin Nutr 1984;39:656.
      2. Tompsett SL. Factors influencing the absorption of iron and copper from the alimentary tract. Biochem J 1940;34:961-9.
    • Famotidine

      Iron

      Replenish Depleted Nutrients

      Stomach acid may increase absorption of iron from food. H-2 blocker drugs reduce stomach acid and are associated with decreased dietary iron absorption. The iron found in supplements is available to the body without the need for stomach acid. People with ulcers may be iron deficient due to blood loss. If iron deficiency is present, iron supplementation may be beneficial. Iron levels in the blood can be checked with lab tests.

      Iron
      Famotidine
      ×
      1. Aymard JP, Aymard B, Netter P, et al. Haematological adverse effects of histamine H2-receptor antagonists.Med Toxicol Adverse Drug Exp 1988;3:430-48.
    • Famotidine

      Vitamin B12

      Replenish Depleted Nutrients

      Stomach acid is needed for the vitamin B12 in food to be absorbed. H-2 blocker drugs reduce stomach acid and may therefore inhibit absorption of the vitamin B12 naturally present in food. However, the vitamin B12 found in supplements does not depend on stomach acid for absorption. Lab tests can determine vitamin B12 levels in people.

      Vitamin B12
      Famotidine
      ×
      1. Aymard JP, Aymard B, Netter P, et al. Haematological adverse effects of histamine H2-receptor antagonists.Med Toxicol Adverse Drug Exp 1988;3:430-48.
The Drug-Nutrient Interactions table may not include every possible interaction. Taking medicines with meals, on an empty stomach, or with alcohol may influence their effects. For details, refer to the manufacturers’ package information as these are not covered in this table. If you take medications, always discuss the potential risks and benefits of adding a new supplement with your doctor or pharmacist.

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