Amoxicillin/Clavulanate (Augmentin®, Clavamox®)*
Class: β-lactam/ β-lactamase inhibitor combination
Amoxicillin is a type of aminopenicillin, a semisynthetic group of β-lactams that
was developed for effectiveness against both gram-negative and gram-positive
organisms. Aminopenicillins were created by joining penicillin to an amino group or side
chain. Addition of the side chain significantly changed the activity of the drug against
some bacteria. Initially these antimicrobials were effective against Proteus mirabilis, E.
coli, Shigella, Salmonella, Hemophilus and Neisseria species. However due to changes
in susceptibility, aminopenicillins are no longer the drug of choice in treating several of
Clavulanate was added to amoxicillin to give the combination drug greater
activity against those organisms that produce non-group 1 (class A) β-lactamases. The
mechanisms of action of amoxicillin/clavulanate are interference with cell wall synthesis
by attachment to penicillin-binding proteins (PBPs), inhibition of cell wall peptidoglycan
synthesis and inactivation of inhibitors to autolytic enzymes. Amoxicillin and its
clavulanate combination can be administered orally.
As with other β-lactams the mechanisms of resistance against amoxicillin and
amoxicillin combinations are production of β-lactamases, alteration of penicillin binding
proteins and decreased permeability through the bacterial cell wall.
Amoxicillin/clavulanate is commonly used to treat acute otitis media in humans.
Short course high dose treatment regimens of amoxicillin/clavulanate may improve
tolerability and adherence of the drug and prevent increases in resistance and improve
efficacy. The combination drug is considered one of the most efficacious antibiotics for
acute bacterial rhinosinusitis in humans. In fact short course high dose therapy with
amoxicillin/clavulanate and fluoroquinolones are the antimicrobial agents of choice in