Pronunciation /fəˈmɒtɪdiːn/ AHFS/Drugs.com Monograph License data US FDA: Famotidine Molar mass 337.449 g/mol | Trade names Pepcid, others MedlinePlus a687011 CAS ID 76824-35-6 | |
Pregnancycategory AU: B1US: B (No risk in non-human studies) | ||
Overview famotidine used to treat ulcers gerd erosive esophagitis and others
Famotidine, sold under the trade name Pepcid among others, is a histamine H2 receptor antagonist that inhibits stomach acid production. It is commonly used in the treatment of peptic ulcer disease and gastroesophageal reflux disease.
Contents
- Overview famotidine used to treat ulcers gerd erosive esophagitis and others
- Famotidine nursing considerations side effects and mechanism of action pharmacology for nurses
- Medical uses
- Preparations
- Side effects
- History
- Research
- References
Unlike cimetidine, the first H2 antagonist, famotidine has no effect on the cytochrome P450 enzyme system, and does not appear to interact with other drugs.
It was discovered in 1979.
Famotidine nursing considerations side effects and mechanism of action pharmacology for nurses
Medical uses
Famotidine is also given to dogs and cats with acid reflux. Famotidine has been used in combination with an H1 antagonist to treat and prevent urticaria caused by an acute allergic reaction.
Preparations
Certain preparations of famotidine are available over the counter (OTC) in various countries. In the United States and Canada, 10 mg and 20 mg tablets, sometimes in combination with an antacid, are available OTC. Larger doses still require a medical prescription.
Formulations of famotidine in combination with ibuprofen were marketed by Horizon Pharma under the trade name Duexis.
Side effects
Side effects associated with famotidine use include headache, dizziness, and constipation or diarrhea.
History
Famotidine was developed by Yamanouchi Pharmaceutical Co. It was licensed in the mid-1980s by Merck & Co. and is marketed by a joint venture between Merck and Johnson & Johnson. The imidazole ring of cimetidine was replaced with a 2-guanidinothiazole ring. Famotidine proved to be 9 times more potent than ranitidine, and 32 times more potent than cimetidine.
It was first marketed in 1981. Pepcid RPD orally disintegrating tablets were released in 1999. Generic preparations became available in 2001, e.g. Fluxid (Schwarz) or Quamatel (Gedeon Richter Ltd.).
In the United States and Canada, a product called Pepcid Complete, which combines famotidine with an antacid in a chewable tablet to quickly relieve the symptoms of excess stomach acid, is available. In the UK, this product was known as Pepcidtwo prior to its discontinuation in April 2015.
Famotidine suffers from poor bioavailability (50%), as it is poorly soluble in the low pH of the stomach. When used in combination with antacids, it promotes local delivery of these drugs to the receptor of the parietal cell wall. Therefore, researchers are developing innovative formulations of tablets, such as gastroretentive drug delivery systems. Such tablets are retained in the stomach for a longer period of time, thereby improving the bioavailability of drugs. Local delivery also increases bioavailability at the stomach wall receptor site and increases the efficacy of drugs to reduce acid secretion.
Research
Famotidine has been investigated as an adjunct in treatment-resistant schizophrenia. In one trial, it caused a 10% reduction in schizophrenic symptom severity in treatment-resistant patients.