Fixbact Mechanism of Action

Pharmacology: Pharmacodynamics: Cefixime exerts its bactericidal activity by interfering with the synthesis of the bacterial cell wall. It binds to specific penicillin-binding proteins responsible for the synthesis of peptidoglycan, a heteropolymeric structure that gives the cell wall its mechanical stability. The final stage of peptidoglycan synthesis involves completion of the cross-linking of the terminal glycine residue of the pentaglycine bridge to the fourth residue of the pentapeptide. The transpeptidase that catalyzes this step is inhibited by cephalosporins. Thus, inhibition of the transpeptidase interrupts peptidoglycan synthesis, causing formation of defective cell walls and osmotically unstable spheroplasts and lysis of the bacteria.
Pharmacokinetics: Cefixime is about 30% to 50% absorbed after oral administration; food has no effect on its absorption. Peak serum concentrations (C_max) after a single, oral 200 or 400 mg dose of cefixime as capsule, tablet or oral suspension are attained between 2 to 6 hours. Although there are differences in pharmacokinetic parameters between the formulations, results of controlled, cross-over studies in healthy adults indicate that the capsules are essentially bioequivalent to tablets. However, oral suspension is more completely absorbed than tablets, thus, tablets theoretically should not be substituted for oral suspension.