Onset of Action and Efficacy of Famotidine

Pharmacodynamic Properties

The American Gastroenterological Association notes that intramuscular administration of famotidine provides approximately 6 hours of acid suppression 2

The American College of Gastroenterology recommends that PPIs are more effective than H2-receptor antagonists, including famotidine, for treating esophageal GERD syndromes and healing esophagitis 3
For short-term symptom relief or on-demand therapy, famotidine's rapid onset makes it useful when immediate effect is needed, as suggested by the American Gastroenterological Association 3

The American Heart Association suggests that patients on dual antiplatelet therapy should receive famotidine instead of PPIs, as famotidine does not interfere with clopidogrel's antiplatelet activity 2
The American College of Gastroenterology notes that all H2-receptor antagonists, including famotidine, develop tachyphylaxis within 6 weeks of continuous use, significantly limiting their effectiveness for long-term therapy 2
Standard-dose famotidine is ineffective for preventing NSAID-related gastric ulcers, though it reduces duodenal ulcers, as reported by the American Gastroenterological Association 4