levobupivacaine: profile and news

Chirocaine ^® should be used with caution in patients receiving other local anesthetics or agents structurally related to amide-type local anesthetics since the toxic effects of these drugs could be additive. In vitro studies indicate CYP3A4 isoform and CYP1A2 isoform mediate the metabolism of levobupivacaine to desbutyl levobupivacaine and 3-hydroxy levobupivacaine, respectively. Thus agents likely to be concomitantly administered with Chirocaine that are metabolized by this isoenzyme family may potentially interact with Chirocaine. Although no clinical studies have been conducted, it is likely that the metabolism of levobupivacaine may be affected by the known CYP3A4 inducers (such as phenytoin, phenobarbital, rifampin), CYP3A4 inhibitors (azole antimycotics e.g., ketoconazole; certain protease inhibitors e.g., ritanovir; macrolide antibiotics e.g., erythromycin; and calcium channel antagonists e.g., verapamil), CYP1A2 inducers (omeprazole) and CYP1A2 inhibitors (furafylline and clarithromycin). Dosage adjustment may be warranted when levobupivacaine is concurrently administered with CYP3A4 inhibitors and CYP1A2 inhibitors as systemic levobupivacaine levels may rise resulting in toxicity.