A beta-lactamase inhibitor is a drug given in conjunction with a beta-lactam antibiotic. Although the inhibitor does not usually have significant antibiotic activity on its own,^[1] it still plays an important role by disabling or slowing down the action of beta-lactamase.

Beta-lactamase inhibitors in clinical use include clavulanic acid and its potassium salt (usually combined with amoxicillin or ticarcillin), sulbactam and tazobactam.