Class: Histamine H2 Antagonist
Dosage Forms. Tablet: 75 mg, 150 mg, 300 mg; Capsule: 150 mg, 300 mg; Syrup: 15 mg/mL
Common FDA Label Indication, Dosing, and Titration.
1. Duodenal ulcer, acute or maintenance, gastric ulcer, acute or maintenance, erosive esophagitis, acute or maintenance: Children 1 mo to 16 y: 2-4 mg/kg po bid, max of 300 mg/d; Adults: 150 mg po bid or 300 mg po daily hs
2. Indigestion, prevention or treatment: 75-150 mg po bid
1. Helicobacter pylori GI tract infection, quadruple therapy: 150 mg po bid × 10-14 d in combination with metronidazole 250 mg po qid, bismuth subsalicylate 525 mg po qid, and tetracycline 500 mg po qid
2. Stress ulcer prophylaxis: 150 mg po bid
MOA. Ranitidine is a competitive inhibitor of histamine H2 receptors. The primary clinically important pharmacologic activity of ranitidine is inhibition of gastric secretion. Both the acid concentration and volume of gastric secretion are suppressed by ranitidine, while changes in pepsin secretion are proportional to volume output.
Drug Characteristics: Ranitidine
Medication Safety Issues: Ranitidine
Drug Interactions: Ranitidine
Adverse Reactions: Ranitidine
Efficacy Monitoring Parameters. Resolution of gastrointestinal discomfort, resolution of ulcers shown on endoscopy.
Toxicity Monitoring Parameters. Severe blistering skin rash.
Key Patient Counseling Points. Advise patients to take at bedtime. Patients may take with food or antacids, if needed.
Clinical Pearls. This and other PPI and H2 antagonists available OTC; warn patients not to take multiple products concurrently to avoid additive risk of adverse effects. Injectable dosage form also available; when the intravenous route is used, treatment should be converted to oral route as soon as possible to avoid cost and risks associated with intravenous therapy.