What is the use of Famotidine (Histamine-2 (H2) receptor antagonist)?

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From the Guidelines

Famotidine is a suitable alternative to proton pump inhibitors (PPIs) for patients taking dual-antiplatelet therapy, as it does not interfere with the antiplatelet activity of clopidogrel, according to the FDA 1.

Use of Famotidine

Famotidine is a histamine-2 (H2) blocker medication primarily used to reduce stomach acid production and treat conditions like heartburn, acid reflux, gastroesophageal reflux disease (GERD), and peptic ulcers.

  • The typical adult dosage is 20-40 mg once or twice daily, with 20 mg usually sufficient for heartburn relief and 40 mg often prescribed for ulcer treatment.
  • For over-the-counter use, the standard dose is 10-20 mg as needed.
  • Famotidine works by blocking histamine receptors in the stomach lining, which decreases acid secretion by the parietal cells.

Benefits of Famotidine

This medication begins working within an hour and its effects can last 10-12 hours.

  • Common brand names include Pepcid, Pepcid AC, and Pepcid Complete.
  • Famotidine is generally well-tolerated with minimal side effects, though headache, dizziness, and constipation may occur.
  • It's essential to take famotidine as directed, typically 15-60 minutes before meals for preventive use or when symptoms occur for relief.

Comparison to Proton Pump Inhibitors

Unlike proton pump inhibitors, famotidine doesn't require several days to reach full effectiveness and can be used intermittently as needed.

  • The FAMOUS trial, a phase II, double-blind, randomized, placebo-controlled trial, found that among patients with a history of coronary heart disease, diabetes mellitus, or cerebrovascular disease who were taking low-dose ASA, 12 weeks of famotidine 20 mg twice daily was beneficial in reducing the incidence of peptic ulcer or esophagitis during follow-up endoscopy at 12 weeks 1.
  • The use of famotidine is recommended as an alternative to PPIs in patients taking dual-antiplatelet therapy, as it does not interfere with the antiplatelet activity of clopidogrel, according to the FDA 1.

From the FDA Drug Label

12.1 Mechanism of Action Famotidine is a competitive inhibitor of histamine-2 (H2) receptors. The primary clinically important pharmacologic activity of famotidine is inhibition of gastric secretion. 12. 2 Pharmacodynamics Adults Famotidine inhibited both basal and nocturnal gastric secretion, as well as secretion stimulated by food and pentagastrin.

The use of Famotidine, a Histamine-2 (H2) receptor antagonist, is to inhibit gastric secretion, suppressing both the acid concentration and volume of gastric secretion.

  • The primary clinically important pharmacologic activity of famotidine is the inhibition of gastric secretion.
  • Famotidine is used to inhibit basal and nocturnal gastric secretion, as well as secretion stimulated by food and pentagastrin 2.

From the Research

Uses of Famotidine

Famotidine is a highly selective histamine H2-receptor antagonist with several uses, including:

  • Healing duodenal and gastric ulcers, with healing rates and symptom relief similar or superior to those achieved by cimetidine and ranitidine 3, 4
  • Preventing recurrence of duodenal ulcer, although comparative trials are needed to establish its relative efficacy in maintenance therapy 3, 4
  • Treating gastritis and reflux gastro-oesophagitis, with doses of 10 to 20mg twice daily 3
  • Treating upper gastrointestinal bleeding, with efficacy similar to cimetidine 3
  • Preventing pulmonary aspiration of acid, with efficacy similar to ranitidine 3
  • Controlling acid secretion in patients with Zollinger-Ellison syndrome, with a mean daily dose of 0.24g 5
  • Managing gastro-oesophageal reflux disease, with 70% of patients experiencing complete day-time heartburn relief and 75% experiencing complete night-time heartburn relief 6

Therapeutic Indications

Famotidine is indicated for the treatment of:

  • Duodenal ulcer
  • Gastric ulcer
  • Gastroesophageal reflux disease
  • Zollinger-Ellison syndrome 7

Dosage and Administration

Famotidine can be administered in various doses, including:

  • 20mg twice daily or 40mg at bedtime for healing duodenal and gastric ulcers 3, 4
  • 10 to 20mg twice daily for treating gastritis and reflux gastro-oesophagitis 3
  • Up to 800mg daily for patients with Zollinger-Ellison syndrome or other conditions requiring high doses 7

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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