Hyperacidity, GERD, and ulcers:
Indications for: Cimetidine
Active duodenal or benign gastric ulcer. Maintenance of healed duodenal ulcers. Pathological hypersecretory conditions (eg, Zollinger-Ellison syndrome). GERD.
Active duodenal ulcer: 800mg at bedtime for 4–8 weeks. Maintenance: 400mg at bedtime. Active benign gastric ulcer: 800mg at bedtime or 300mg 4 times daily with meals and at bedtime for 6 weeks. Hypersecretory conditions: 300mg 4 times daily with meals and at bedtime; max 2.4g/day. GERD: 800mg 2 times daily or 400mg 4 times daily for max 12 weeks; see full labeling. For difficult to heal ulcers: see full labeling.
<16yrs: not recommended; see full labeling. Doses of 20–40mg/kg per day have been used.
Impaired renal or hepatic function. Elderly. Debilitated. Immunocompromised. Pregnancy (Cat.B). Nursing mothers: not recommended.
Avoid antacids within 1 hour of dosing. May potentiate anticoagulants, phenytoin, theophylline, lidocaine, and others (see literature) by inhibition of hepatic microsomal enzymes. May alter absorption of drugs affected by gastric pH (e.g., ketoconazole), give 2 hours before cimetidine.
Headache, diarrhea, dizziness, somnolence, CNS disturbances, gynecomastia, rash (maybe serious eg, Stevens-Johnson syndrome); rare: arthralgia, myalgia, blood dyscrasias, nephritis, increased serum transaminases, pancreatitis, bradycardia, tachycardia; increased risk of community-acquired pneumonia (see literature).
Formerly known under the brand name Tagamet.