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Name: Famotidine

Pregnancy Category B

Drug classes

  • Histamine2 (H2) antagonist

Therapeutic actions

Competitively blocks the action of histamine at the histamine (H2) receptors of the parietal cells of the stomach; inhibits basal gastric acid secretion and chemically induced gastric acid secretion.


  • Short-term treatment and maintenance of duodenal ulcer
  • Short-term treatment of benign gastric ulcer
  • Treatment of pathologic hypersecretory conditions
  • Short-term treatment of gastroesophageal reflux disease (GERD), esophagitis due to GERD


  • Allergy to famotidine; renal failure; pregnancy; lactation.

Adverse effects

  • CNS: Headache, malaise, dizziness, somnolence, insomnia
  • GI: Diarrhea, constipation, anorexia, abdominal pain
  • Dermatologic: Skin rash
  • Other: Muscle cramp, increase in total bilirubin, sexual impotence

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