Prilocaine—An Underutilized Local Anesthetic

Abstract

The pharmacology and clinical use of prilocaine, an amide local anesthetic, are reviewed and compared with the properties of lidocaine—the standard drug of the group. In terms of potency and rate of onset, prilocaine is at least the equal of lidocaine, and, in most situations, it seems to have a slightly longer duration of action. Its outstanding feature is its lower systemic toxicity, because of a combination of a slower rate of absorption from the site of injection, greater tissue distribution, and more rapid metabolism than lidocaine. This means that prilocaine is particularly indicated for use during regional anesthetic techniques in which the risk of systemic toxicity is particularly high. Because of its safety, it also has much to offer the beginner as the standard drug for all block procedures. Its metabolites may cause methemoglobinemia, but, unless very large doses are employed, this complication is only a theoretical one that, in any case, is very easy to treat.