β-Lactamase Inhibitors



β-Lactamase Inhibitors

β-lactamase inhibitors potentiate / reestablish the antibacterial potency of penicillinase sensitive penicillins against β lactamase producing organisms by inhibiting the enzyme. These are structurally similar to penicillin and act as substitutes for penicillinase, causing inhibition of the enzyme.
These drugs have poor antimicrobial activity. They are inhibitors of bacterial beta-lactamase. (Suicidal inhibition). They are potent inhibitors of many bacterial beta-lactamases and can protect hydrolyzable penicillins from inactivation by these enzymes. They are included in combination with amoxacillin (Augmentum) or with ticaricillin. In particular, clavulanic acid is an irreversible, "suicide" inhibitor of beta-lactamase. (Potentiated penicillins)
e.g. Clavulanic Acid, Sulbactam and Tazobactam
Clavulanic acid
Obtained from S. clavuligerus, has no antibacterial activity of its own. Generally combined with Amoxicillin (2:1) or Ticarcillin (15:1)
Sulbactam
A semi-synthetic penicillinase inhibitor related chemically and in activity to clavulanic acid. Combined with ampicillin and preferably for oral and pareneteral admn.
Tazobactam
Similar to sulbactam and combined with piperacillin.
Penicillins with sulbactam and tazobactam are administered IV; whereas, those with clavulanic acid are administered orally or IV.
They are available only in fixed combinations with specific penicillins:
Ampicillin + sulbactam
Amoxicillin + clavulanic acid
Ticarcillin + clavulanate potassium
Piperacillin + tazobactam sodium

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