Cloxacillin

Cloxacillin

Clinical data
Trade names	Cloxapen, others
AHFS/Drugs.com	Micromedex Detailed Consumer Information
Pregnancy category	US: B (No risk in non-human studies)
Routes of administration	by mouth, IM
ATC code	J01CF02 (WHO) QJ51CF02 (WHO) QS01AA90 (WHO)
Pharmacokinetic data
Bioavailability	37 to 90%
Protein binding	95%
Biological half-life	30 minutes to 1 hour
Excretion	kidney and biliary
Identifiers
IUPAC name (2S,5R,6R)-6-{[3-(2-chlorophenyl)-5-methyl- oxazole-4-carbonyl]amino}-3,3-dimethyl-7-oxo- 4-thia-1-azabicyclo[3.2.0]heptane-2-carboxylic acid
CAS Number	61-72-3 Y
PubChem CID	6098
DrugBank	DB01147 Y
ChemSpider	5873 Y
UNII	O6X5QGC2VB
KEGG	D07733 Y
ChEBI	CHEBI:49566 Y
ChEMBL	CHEMBL891 Y
ECHA InfoCard	100.000.468
Chemical and physical data
Formula	C19H18ClN3O5S
Molar mass	435.88 g/mol
3D model (Jmol)	Interactive image
SMILES O=C(O)[C@@H]3N4C(=O)[C@@H](NC(=O)c2c(onc2c1ccccc1Cl)C)[C@H]4SC3(C)C
InChI InChI=1S/C19H18ClN3O5S/c1-8-11(12(22-28-8)9-6-4-5-7-10(9)20)15(24)21-13-16(25)23-14(18(26)27)19(2,3)29-17(13)23/h4-7,13-14,17H,1-3H3,(H,21,24)(H,26,27)/t13-,14+,17-/m1/s1 Y Key:LQOLIRLGBULYKD-JKIFEVAISA-N Y

Cloxacillin is an antibiotic useful for the treatment of a number of bacterial infections. This includes impetigo, cellulitis, pneumonia, septic arthritis, and otitis externa. It is not effective for Methicillin-resistant Staphylococcus aureus (MRSA). It is used by mouth and by injection.

Side effects include nausea, diarrhea, and allergic reactions including anaphylaxis.Clostridium difficile diarrhea may also occur. It is not recommended in people who have previously had a penicillin allergy. Use during pregnancy appears to be relatively safe. Cloxacillin is in the penicillin family of medications.

Cloxacillin was patented in 1960 and approved for medical use in 1965. It is on the World Health Organization's List of Essential Medicines, the most effective and safe medicines needed in a health system. The wholesale cost in the developing world is about 0.16 USD per day for the pills. It is not commercially available in the United States.

It is semisynthetic and in the same class as penicillin. Cloxacillin is used against staphylococci that produce beta-lactamase, due to its large R chain, which does not allow the beta-lactamases to bind. This drug has a weaker antibacterial activity than benzylpenicillin, and is devoid of serious toxicity except for allergic reactions.