Famotidine is a highly selective
histamine H2-receptor antagonist. In healthy volunteers and patients with
acid hypersecretory disease it is approximately 20 to 50 times more potent at inhibiting gastric acid secretion than
cimetidine and 8 times more potent than
ranitidine on a weight basis. As shown in placebo-controlled trials,
famotidine is effective in healing both duodenal and
gastric ulcers.
Famotidine 20mg twice daily or 40mg at bedtime achieves healing rates and symptom relief similar or superior to those achieved by
cimetidine 800mg daily or
ranitidine 300mg daily in patients with
peptic ulcer disease. Results of 1 placebo-controlled study suggest that
famotidine prevents recurrence of
duodenal ulcer, but comparative trials are needed to establish its relative efficacy in maintenance
therapy. The few non-comparative trials conducted to date also suggest that
famotidine 10 to 20mg twice daily may be effective in the treatment of
gastritis and reflux gastro-oesophagitis. In comparative trials,
famotidine was similar in efficacy to
cimetidine in the treatment of upper gastrointestinal
bleeding and to
ranitidine in the prevention of pulmonary aspiration of
acid. In patients with
Zollinger-Ellison syndrome, the potency and long duration of action of
famotidine may confer an advantage over other H2-receptor antagonists--in individualised doses (mean 0.33 g/day)
famotidine successfully controlled
acid secretion for up to 72 months in 1 study of such patients. Accumulated clinical evidence confirms that
famotidine is very well tolerated and is free of the antiandrogenic effects infrequently reported with
cimetidine. Moreover,
famotidine is not associated with altered hepatic metabolism of drugs. Thus,
famotidine is an effective, well-tolerated alternative to
cimetidine and
ranitidine.
Famotidine is also promising as maintenance
therapy for preventing recurrence of
duodenal ulcer and as initial or maintenance treatment of gastric hypersecretory disorders, but further clinical experience, particularly in the long term, is needed to define the relative efficacy and tolerability of
famotidine in these indications.