Clavicin Mechanism of Action

Pharmacology: Resistance to many antibiotics is caused by bacterial enzymes which destroy the antibiotic before it can act on the pathogen. The clavulanate in Amoxicillin and Clavulanic acid anticipates this defence mechanism by blocking the organisms sensitive to amoxicillin's rapid bactericidal effect at concentrations rapidly attainable in the body.
Clavulanate by itself has little antibacterial activity; however in association with amoxicillin as Amoxicillin and Clavulanic acid, it produces an antibiotic agent of broad spectrum with wide application in hospital and general practice.
Pharmacodynamics: Amoxicillin and Clavulanic acid combination is bactericidal to a wide range of organisms including: Gram-positive: Aerobes: Enterococcus faecalis*, Enterococcus faecium*, Streptococcus pneumoniae, Streptococcus pyogenes, Streptococcus viridans, Staphylococcus aureus*, Coagulase negative staphylococci* (including Staphylococcus epidermidis*), Corynebacterium sp, Bacillus anthracis *, Listeria monocytogenes.
Anaerobes: Clostridium sp, Peptococcus sp, Peptostreptococcus.
Gram-negative: Aerobes: Haemophilus influenzae*, Moraxella catarrhalis* (Branhamella catarrhalis), Eschirichia coli*, Proteus mirabilis*, Proteus vulgaris*, Klebsiella sp*, Salmonella sp*, Shigella sp*, Bordetella pertussis, Brucella sp, Neisseria gonorrhoeae*, Neiserria meningitidis*, Vibrio cholerae, Pasteurella multocida.
Anaerobes: Bacteroides sp* including B. fragilis.
* Some members of these species of bacteria produce β-lactamase, rendering them insensitive to amoxicillin alone.
Pharmacokinetics: The pharmacokinetics of the 2 components of Amoxicillin and Clavulanic acid are closely matched. Both clavulanate and amoxicillin have low levels of serum binding; about 70% remains free in the serum. Doubling the dosage of the Amoxicillin and Clavulanic acid approximately doubles the serum levels achieved.
When taken together with amoxicillin (500 mg), absorption of clavulanic acid (250 mg) is approximately the same, with a serum peak of around 6 mg.1^-1 and a peak amoxicillin level of 10 mg.1^-1, both after 1h. The urinary recovery is about 27-32% after a 250mg dose of clavulanic acid in combination with amoxicillin. The plasma half-life is 0.8-1h and plasma protein binding is 22-30%.
The activity of clavulanic acid is dependent upon the drug achieving concentrations at the site of action above the minimum inhibitory concentration (MIC).