Famotidine (Pepcid)


  • Gastrointestinal


  • Antiulcer agent (H2 antagonist)


  • Short term and maintenance duodenal ulcer therapy

  • Short term benign gastric ulcer therapy

  • Pathological hypersecretory conditions (Zollinger-Ellison syndrome)

  • Gastroesophageal disease (GERD) and esophagitis due to GERD

Drug Interactions:

  • Reduction of gastric acidity reduces absorption and introduces potential for therapeutic failure: ketoconazole, enoxacin, cefpodoxime, cefuroxime

  • Increased absorption, potential for hypoglycemia: glipizide, glyburide

  • Increased concentrations: nifedipine, nisoldipine


  • Pregnancy category B; concentrated in breast milk (but less than cimetadine or ranitadine, but considered compatible with breast feeding)

  • Symptomatic response does not rule out gastric malignancy

Adverse Reactions (Side Effects):

  • CNS: anxiety, depression, dizziness, fever, headache, insomnia, paresthesia, seizures, somnolence

  • EENT: Orbital edema, taste change, tinnitis

  • HEME: Thrombocytopenia

  • RESP: Bronchospasm

  • Arthralgia, myalgia, rash


Available orally (suspension, tablet) and intravenously

  • Adult Dose:

    • Duodenal ulcer: 

      • 40mg orally every night at bedtime for 4-8 weeks, then 20mg thereafter if needed for maintenance.  

      • IV; 20mg every 12 hours if unable to tolerate PO

    • Gastric Ulcer: 

      • 40mg orally every night at bedtime

    • GERD: 

      • PO 20mg twice daily for up to 6 weeks; for esophagitis due to GERD, 20-40mg twice daily for up to 12 weeks

    • Hypersecretory conditions: 

      • PO 20mg every 6 hours; may give 160mg every 6 hours if needed.  

      • IV 20mg every 12 hours if unable to tolerate PO

    • Heartburn or acid indigestion: 

      • PO 10mg twice daily; to prevent heartburn, 10mg 1 hour before meals

    • Renal failure: 

      • PO 20mg at bedtime or increase dosing interval to 36-48 hours

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