Brofoxin Mechanism of Action

Pharmacological Classification: Antibacterial.
Pharmacology: Mechanism of Action: Cefoxitin is a cephamycin antibacterial which, like the other beta lactams, is bactericidal and is considered to act through the inhibition of bacterial cell wall synthesis. It has a similar spectrum of activity to cefamandole but is more active against anaerobic bacteria, especially Bacteroides fragilis. Cefoxitin can induce the production of beta-lactamases by some bacteria, and use of cefoxitin with other beta lactams have been shown to be antagonistic in vitro. Cefoxitin itself is considered to be resistant to a wide range of beta-lactamases, including those produced by Bacteroides spp. However, acquired resistance to cefoxitin has been reported in B. fragilis and has been attributed to beta-lactamase as well as to alterations in penicillin-binding proteins or to outer membrane proteins; there may be cross-resistance to other antibacterials.
Pharmacokinetics: Absorption: Not absorbed from the gastrointestinal tract; given parenterally as sodium salt.
Administration: Intramuscular (IM) injection: After 1 g, peak plasma concentration up to 30 μg/mL at 20-30 minutes.
Intravenous (IV) administration: 1 g over 3 minutes: 125 μg/mL, 1 g over 30 minutes: 72 μg/mL, 1 g over 120 minutes: 25 μg/mL.
Distribution: About 70% bound to plasma proteins.
Plasma half-life: 45-60 minutes (prolonged in renal impairment).
Widely distributed in the body.
Little penetration into CSF, even with inflamed meninges.
Crosses the placenta and detected in breast milk.
High concentrations in bile.
Metabolism: Majority excreted unchanged by kidneys.
Up to 2% metabolized to descarbamylcefoxitin (virtually inactive).
Excretion: Excreted in urine by glomerular filtration and tubular secretion.
About 85% of dose recovered within 6 hours; slowed by probenecid.
Peak urine concentrations >3 mg/mL after 1 g IM dose.
Removed to some extent by hemodialysis.