Famotidine

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Famotidine
Systematic (IUPAC) name
2-[4-[2-(amino-sulfamoylimino-methyl) ethylsulfanylmethyl]-1,3-thiazol-2-yl]guanidine
Identifiers
CAS number	76824-35-6
ATC code	A02BA03
PubChem	3325
DrugBank	APRD00296
Chemical data
Formula	C8H15N7O2S3
Mol. mass	337.449 g/mol
Pharmacokinetic data
Bioavailability	20–66%
Protein binding	10–28%
Metabolism	hepatic-less than 30%
Half life	2.5-4 hours (clinical half-life 8-12 hours)
Excretion	Principally excreted unchanged in urine
Therapeutic considerations
Licence data	US
Pregnancy cat.	B1 (Au), B (U.S.)
Legal status	S3/S4 (Au), POM/OTC (UK), OTC/℞-only (U.S.)
Routes	Oral, IV

Famotidine (INN) (pronounced /fəˈmɒtɪdiːn/) is a histamine H₂-receptor antagonist that inhibits stomach acid production, and is commonly used in the treatment of peptic ulcer disease (PUD) and gastroesophageal reflux disease (GERD/GORD). It is commonly marketed by J&J/Merck under the trade names Pepcidine and Pepcid.

[edit] Clinical use

Main article: H2-receptor antagonist

Certain preparations of famotidine are available over the counter (OTC) in various countries. In the United States, preparations of 10 mg and 20 mg tablets, sometimes in combination with a more traditional antacid, are available OTC. Larger doses still require a prescription.

Famotidine is given to surgery patients before operations to prevent post-operation nausea and to reduce the risk of aspiration pneumonitis.

[edit] History and development

Famotidine was developed 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 30 times more active than cimetidine.

It was first marketed in 1985. Pepcid RPD orally-disintegrating tablets (that are not swallowed) was released in 1999. Generic preparations became available in 2001, e.g. Fluxid (Schwarz) or Quamatel (Gedeon Richter Ltd.). In the United States, a product called Pepcid Complete is available that combines famotidine with an antacid in a chewable tablet to ameliorate the relatively slow onset of effects. In the UK, this product is known as Pepcidtwo.

v • d • e Drugs for acid related disorders: Drugs for peptic ulcer and GERD/GORD (A02B) H2 antagonists Cimetidine, Famotidine, Nizatidine, Ranitidine, Roxatidine Prostaglandins/analogues Misoprostol, Enprostil Proton pump inhibitors Esomeprazole, Lansoprazole, Omeprazole, Pantoprazole, Rabeprazole, Tenatoprazole Other Carbenoxolone, Sucralfate, Pirenzepine