Beta-lactamase inhibitors: another approach to overcoming antimicrobial resistance.

Beta-lactamase inhibitors in combination with a beta-lactam antimicrobial agent provide another approach to the treatment of infections caused by many bacteria resistant to commonly used agents. Currently two fixed combinations are commercially available. One is the oral preparation of amoxicillin and potassium clavulanate (Augmentin). The other is for intravenous therapy and combines ticarcillin and potassium clavulanate (Timentin). In vitro studies confirm that the combination of a beta-lactamase inhibitor and a beta-lactam can increase the activity of the beta-lactam to such important pathogens as S aureus, Klebsiella, H influenzae, Bacteroides spp and other bacteria which produce plasmid-mediated beta-lactamase. Clinical efficacy studies have demonstrated potential usefulness of these combinations particularly for therapy of suspected or proven infections caused by mixed aerobic and anaerobic bacteria. The combination of amoxicillin or ticarcillin with clavulanic acid can be used to improve cost-effectiveness of antimicrobial therapy if they replace regimens that use multiple drugs or drugs with a relatively high incidence of adverse reactions.