Clinical Pharmacokinetics and Pharmacodynamics of Levobupivacaine

Levobupivacaine is a long-acting amide local anaesthetic used in analgesia and anaesthesia. Like other local anaesthetic drugs, levobupivacaine exhibits effects on motor and sensory nerves by inhibiting the opening of voltage-gated sodium channels, and hence propagation of neuronal action potentials. Levobupivacaine is the S(-) stereoisomer of dextrobupivacaine, although both are used commercially in the racemic form bupivacaine. A favourable safety and drug effect profile for levobupivacaine has led to widespread use. Levobupivacaine is generally well tolerated but dose adjustment is important in populations such as paediatrics and the elderly. The pharmacokinetic properties of levobupivacaine are similar to that of bupivacaine; both extensively metabolised in the liver, and excreted in the urine and faeces. In vitro, animal model and human studies confirm a lower risk of cardiac and central nervous system toxicity with levobupivacaine compared with bupivacaine. Clinical trials of relative potency are impaired by the variability in chosen endpoints for sensory and motor function blockade, but clinically significant differences in potency are minor, with most clinical trials showing similar duration and quality of anaesthesia between levo- and racemic bupivacaine. In practice, levobupivacaine is most commonly used in regional anaesthesia, neuraxial anaesthesia and local infiltration analgesia. This review includes an appraisal of evidence from clinical trials of the pharmacokinetic and pharmacodynamic properties of levobupivacaine.