famotidine

Famotidine is an oral drug that blocks the production of acid by acid-producing cells in the stomach. Since excessive stomach acid can damage the esophagus, stomach, and duodenum, and lead to inflammation and ulceration, reducing stomach acid prevents and heals acid-induced inflammation and ulcers.

Famotidine belongs to a class of drugs called H2 (histamine-2) blockers that also includes cimetidine (Tagamet), nizatidine (Axid), and ranitidine (Zantac). Histamine is a naturally-occurring chemical that stimulates cells in the stomach (parietal cells) to produce acid. 

Famotidine blocks the action of histamine on stomach cells and reduces the production of acid by the stomach.

• Famotidine is useful in promoting the healing of stomach and duodenal ulcers and in reducing ulcer pain.
• Famotidine has been effective in preventing recurrence of ulcers when given in low doses for prolonged periods of time.
• Famotidine is also used for treating heartburn and in healing ulceration and inflammation of the esophagus (esophagitis) resulting from acid (gastroesophageal reflux disease or GERD).
• High doses are used for treating conditions in which there are marked increases in acid secretion such as Zollinger-Ellison syndrome.
• Over-the-counter preparations are used for treatment and prevention of occasional heartburn associated with acid indigestion (another name for GERD).

Famotidine was approved by the FDA in November 1986.

Side effects of famotidine are rare. The most commonly reported minor side effects are:

• constipation,
• diarrhea,
• fatigue,
• headache,
• insomnia,
• muscle pain,
• nausea, and
• vomiting.

Other important side effects include:

• anemia,
• confusion,
• easy bruising or bleeding,
• hair loss,
• rash,

More serious side effects include:

• depression,
• hallucinations,
• irregular heartbeat,
• visual changes, and
• yellowing of the skin or eyes (jaundice).

• The recommended adult oral dose for treating duodenal ulcers is 40 mg once daily at bedtime or 20 mg twice daily. Most patients heal their ulcers within 4 weeks. The regimen for maintenance therapy after the ulcers are healed is 20 mg once a day at bedtime. The recommended oral dose for adults with gastric ulcers is, 40 mg once daily at bedtime.
• Esophagitis is treated with 20 or 40 mg twice daily for up to 12 weeks. Zollinger-Ellison syndrome is treated with 20 mg every 6 hours, and doses up to 160 mg every 6 hours have been used in some patients.
• GERD is treated with 20 mg twice daily for up to 6 weeks. Occasional heartburn is treated with 10-20 mg daily administered 15 to 60 minutes before ingestion of food or beverages that cause heartburn.

• Famotidine, like other drugs that reduce stomach acid, may interfere with the absorption of drugs that require acid for adequate absorption. Examples include iron salts (for example iron sulphate), itraconazole (Sporanox), and ketoconazole (Nizoral, Extina, Xolegel, Kuric).

• Use of famotidine during pregnancy has not been adequately evaluated.
• Famotidine is secreted into breast milk. Due to the potential but unknown harm that famotidine might cause to the infant, nursing mothers should consider discontinuing famotidine.

What preparations of famotidine are available?

• Tablets: 10, 20, and 40 mg.
• Tablets (Chewable): 10 and 20 mg.
• Suspension: 40 mg per 5 ml (teaspoon). Injection: 10 mg/ml.

How should I keep famotidine stored?

Tablets and suspension should be stored at room temperature, 15 C - 30 C (59 F - 86 F). Injection should be stored between 2 C - 8 C (36 F - 46 F).