Trufix Mechanism of Action

Pharmacology: Pharmacodynamics: Mechanism of Action: The bactericidal action of Cefixime results from inhibition of cell-wall synthesis. Cefixime is highly beta-lactamase stable and as a result many organisms resistant to penicillins and some cephalosporins due to the presence of beta-lactamases may be susceptible to Cefixime. Clinical efficacy has been demonstrated in infections caused by commonly occurring pathogens including Streptococcus pneumoniae, Streptococcus pyogenes, Escherichia coli, Proteus mirabilis, Klebsiella species, Haemophilus influenzae (beta-lactamase positive and negative), Branhamella catarrhalis (beta-lactamase positive and negative) and Enterobacter species.
Most strains of Streptococcus faecalis, group D Staphylococci (including coagulase positive and negative strains and methicillin-resistant strains) are resistant to Cefixime. In addition, most strains of Pseudomonas, Bacteroides fragilis, Listeria monocytogenes and Clostridia are resistant to Cefixime.
Pharmacokinetics: Cefixime, given orally, is about 40% to 50% absorbed whether administered with or without food; however, time to maximal absorption is increased approximately 0.8 hours when administered with food. A single 200 mg capsule of Cefixime produces an average peak serum concentration of approximately 2 mcg/mL. Peak serum concentration following oral administration of the absorbed dose is excreted unchanged in the urine in 24 hours. In animal studies, it was noted that Cefixime is also excreted in bile in excess of 10% of the administered dose. Serum protein binding is concentration independent with a bound fraction of approximately 65%. The serum half-life of Cefixime in healthy subjects is independent of dosage form and average 3 to 4 hours. In subjects with moderate impairment of renal function, (20 to 40 mL/minute creatinine clearance), the average serum half-life of Cefixime is prolonged to 6.4 hours. In severe renal impairment (5 to 20 mL/minute creatinine clearance), the average serum half-life of Cefixime is prolonged to 11.5 hours. There is no evidence of metabolism of Cefixime in vivo.