Littmox Mechanism of Action

Pharmacology: Pharmacodynamics and Pharmacokinetics: Amoxicillin exerts its bactericidal activity by interfering with the bacterial cell wall synthesis. Peptidoglycan is a heteropolymeric structure that provides the cell wall with mechanical stability. The final stage of peptidoglycan synthesis involves the completion of the cross-linking when the terminal glycine residue of the pentaglycine bridge is linked to the fourth residue of the pentapeptide. The transpeptidase that catalyzes this step is inhibited by penicillins. As a result, the bacterial cell wall is weakened, the cell swells, and then ruptures. Amoxicillin is readily hydrolyzed by the staphylococcal penicillinase.
Amoxicillin is a broad spectrum aminopenicillin antibiotic that is structurally related to ampicillin. It is rapidly bactericidal against susceptible organisms during the stage of active multiplication. It is ineffective in most staphylococcal infections since it is destroyed by β-lactamase.
Amoxicillin is active in vitro and in clinical infections against most strains of the following microorganisms: See Table 1.

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Amoxicillin is a semi-synthetic penicillin and a close chemical and pharmacological relative to Ampicillin. The drug is stable in acid and is designed for oral use. The antimicrobial spectrum of amoxicillin is essentially identical to that of Ampicillin with the important exception that Amoxicillin appears to be less effective than Ampicillin for shigellosis. Amoxicillin is more rapidly and completely absorbed from the gastrointestinal tract than ampicillin which is the major difference between the two. Peak concentration in plasma are two and one-half times greater for amoxicillin than ampicillin after oral administration of the same doses. Food does not interfere with absorption, perhaps because of more complete absorption of this congener.
Amoxicillin is stable in the presence of gastric acid and is rapidly absorbed after oral administration. Amoxicillin diffuses readily into most body tissues and fluids, with the exception of brain and spinal fluid, except when meninges are inflamed. The half-life of amoxicillin is 61.3 minutes. Most of the amoxicillin is excreted unchanged in the urine; its excretion can be delayed by concurrent administration of probenecid. In blood serum, amoxicillin is approximately 20% protein-bound. Orally administered doses of 250-mg and 500-mg amoxicillin capsules result in average peak blood levels 1 to 2 hours after administration in the range of 3.5 mcg/mL to 5.0 mcg/mL and 5.5 mcg/mL to 7.5 mcg/mL, respectively.