Acid Control Disease Interactions

Histamine H2 receptor antagonists should not be used in the presence of vomit with blood, or bloody or black stools. These might be serious conditions and the diagnosis needs to be ruled out.

Famotidine is partially eliminated by the kidney as unchanged drug, the extent of which is dependent upon the route of administration (25% to 30% oral; 65% to 70% intravenous). The elimination half-life of famotidine may be prolonged considerably in patients with severe renal impairment (CrCl < 10 mL/min), possibly exceeding 20 hours and approaching approximately 24 hours in anuric patients. Since central nervous system adverse effects such as grand mal seizures and psychic disturbances have been reported in patients with moderate (CrCl < 50 mL/min) and severe renal impairment, dosage adjustments are recommended for these patients. Reducing the normally recommended dosage by one-half or prolonging the dosing interval to 36 to 48 hours may be appropriate, depending on the patient's clinical response.