Nafcillin

Nafcillin

Clinical data
AHFS/Drugs.com	Monograph
MedlinePlus	a685019
Pregnancy category	US: B (No risk in non-human studies)
Routes of administration	IM, IV
ATC code	J01CF06 (WHO)
Legal status
Legal status	In general: ℞ (Prescription only)
Pharmacokinetic data
Protein binding	90%
Metabolism	<30% hepatic
Biological half-life	0.5 hours
Excretion	Biliary and renal
Identifiers
IUPAC name (2S,5R,6R)-6-[(2-ethoxy-1-naphthoyl)amino]-3,3-dimethyl-7-oxo-4-thia-1-azabicyclo[3.2.0]heptane-2-carboxylic acid
CAS Number	985-16-0 Y
PubChem CID	8982
DrugBank	DB00607 Y
ChemSpider	8634 Y
UNII	SY07234TTS
ChEBI	CHEBI:7447 Y
ChEMBL	CHEMBL1443 Y
ECHA InfoCard	100.005.174
Chemical and physical data
Formula	C21H22N2O5S
Molar mass	414.476 g/mol
3D model (Jmol)	Interactive image
SMILES O=C(O)[C@@H]3N4C(=O)[C@@H](NC(=O)c2c1ccccc1ccc2OCC)[C@H]4SC3(C)C
InChI InChI=1S/C21H22N2O5S/c1-4-28-13-10-9-11-7-5-6-8-12(11)14(13)17(24)22-15-18(25)23-16(20(26)27)21(2,3)29-19(15)23/h5-10,15-16,19H,4H2,1-3H3,(H,22,24)(H,26,27)/t15-,16+,19-/m1/s1 Y Key:GPXLMGHLHQJAGZ-JTDSTZFVSA-N Y

Nafcillin sodium is a narrow-spectrumbeta-lactam antibiotic of the penicillin class. As a beta-lactamase-resistant penicillin, it is used to treat infections caused by Gram-positive bacteria, in particular, species of staphylococci that are resistant to other penicillins.

Nafcillin is considered therapeutically equivalent to oxacillin, although its safety profile is somewhat different.

Nafcillin is indicated in the treatment of staphylococcal infections, except those caused by MRSA.

U.S. clinical practice guidelines recommend either nafcillin or oxacillin as the first-line treatment of choice for staphylococcal endocarditis in patients without artificial heart valves.

As with all penicillins, serious life-threatening allergic reactions can occur.

Milder side-effects include:

There is evidence that it induces enzymes specifically CYP2C9. Several drugs with a narrow theraputic window, such as warfarin and nifedipine, are metabolized by CYP2C9.

Nafcillin contains salts added as stability media. These added salts could cause edema or fluid accumulation. It would be prudent to avoid this medication if there were a concern for a congestive heart failure or kidney disease.