COMPARISON OF INTRAVENOUS FAMOTIDINE AND RANITIDINE IN SUPPRESSING GASTRIC-ACID SECRETION IN CRITICALLY ILL PATIENTS

Histamine(2) (H-2)-receptor antagonists are administered to raise gast ric pH levels and have been found to reduce the risk of stress ulcerat ion and gastrointestinal bleeding in patients admitted to intensive ca re units. This study compared the efficacy of famotidine to ranitidine in raising gastric pH above 4.00 in critically ill patients. Thirty-t wo patients were randomly assigned to receive intravenous bolus doses of either famotidine 20 mg every 12 hours (n = 16) or ranitidine 50 mg every 8 hours (n = 16) for a minimum of 3 days and a maximum of 7 day s, depending on when the nasogastric tube was removed from the patient . Gastric fluid was aspirated before the start of treatment (baseline) and six times during each 24-hour period; pH was measured using a pH meter. Baseline pH (mean +/- SD) was 1.87 +/- 0.42 for the famotidine group and 1.71 +/- 0.31 for the ranitidine group (P > 0.05). Famotidin e elevated gastric pH to higher levels than ranitidine, reaching stati stical significance (P < 0.05) from day 2 to day 7 for 20 of 36 collec tion periods. When averaged over the 7 days, gastric pH was raised to values above 4.00 in 79.4% of collected samples for famotidine, compar ed with 32.6% of samples in the ranitidine group. No adverse events oc curred during treatment with either drug. We concluded that, when give n by intermittent intravenous bolus injection, famotidine 20 mg every 12 hours is more effective than ranitidine 50 mg every 8 hours in elev ating gastric pH to above 4.00 in critically ill patients.