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Name: Ranitidine

Pregnancy Category B

Drug classes

  • Histamine2 (H2) antagonist

Therapeutic actions

Competitively inhibits the action of histamine at the histamine2 (H2) receptors of the parietal cells of the stomach, inhibiting basal gastric acid secretion and gastric acid secretion that is stimulated by food, insulin, histamine, cholinergic agonists, gastrin, and pentagastrin.


  • Short-term treatment of active duodenal ulcer
  • Maintenance therapy for duodenal ulcer at reduced dosage
  • Short-term treatment of active, benign gastric ulcer
  • Short-term treatment of gastroesophageal reflux disease
  • Pathologic hypersecretory conditions (eg, Zollinger-Ellison syndrome)
  • Treatment of erosive esophagitis


  • Contraindicated in the presence of allergy to ranitidine, lactation.
  • Use caution in the presence of impaired renal or hepatic function.

Adverse effects

  • CNS: Headache, malaise, dizziness, somnolence, insomnia, vertigo
  • GI: Constipation, diarrhea, nausea, vomiting, abdominal pain, hepatitis, increased SGPT levels
  • CV: Tachycardia, bradycardia, PVCs (rapid IV administration)
  • Hematologic: Leukopenia, granulocytopenia, thrombocytopenia, pancytopenia
  • GU: Gynecomastia, impotence or loss of libido
  • Dermatologic: Rash, alopecia
  • Local: Pain at IM site, local burning or itching at IV site
  • Other: Arthralgias

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