[EMLA. A new topical anesthetic]

Abstract

The method most widely used at present for cutaneous analgesia is local anesthetic infiltration. Pain occurs when the needle penetrates and when the anesthetic is deposited and diffuses. The procedure is not risk-free. It is therefore not surprising that many attempts have been made to develop an anesthetic formula that is effective when applied topically to intact skin. Early efforts were unsuccessful due to either low analgesic efficacy or side effects. The problem was solved several years ago in the European market by the EMLA (Eutetic Mixture of Local Anesthetics) cream. The EMLA cream has been shown to be useful as a topical anesthetic on either intact or damaged skin. Its clinical profile is safe, with a low incidence of side effects. We feel it is a useful tool for preventing pain in a variety of procedures that call for cutaneous analgesia. It may also be used as premedication for perineural injection of anesthetics, providing greater comfort for the patient. This article describes the main pharmacological principles that make EMLA an effective topical analgesic, as well as indications for its use in the clinical practice of anesthesiology.