Augmentin: laboratory studies.

Clavulanic acid is a beta-lactam antibiotic which, although it has little intrinsic activity, is a potent inhibitor of bacterial beta-lactamases. When combined with amoxycillin its range of activity includes penicillinase-producing strains of Staphylococcus aureus and many of the beta-lactamase-producing strains of Gram-negative bacilli. Bacteria sensitive to augmentin include amoxycillin-resistant strains of Haemophilus influenzae and Escherichia coli, in addition strains of Klebsiella aerogenes, Proteus mirabilis, Proteus vulgaris and Bacteroides fragilis are usually sensitive. The beta-lactamases produced by Enterobacter spp, Proteus morgani, Serratia marcescens and Pseudomonas aeruginosa are less susceptible to clavulanic acid and these bacteria are usually resistant to augmentin (1).