What's New in Topical Anesthesia

Advances in topical anesthesia have brought new products, new drug delivery systems, and new indications. Eutectic mixture of local anesthetics, LMX4, and Synera are available for skin anesthesia before minor skin-breaking procedures such as venipuncture and intravenous cannulation. Several systems to enhance drug delivery, shortening onset of skin anesthesia to 5 minutes or less, are commercially available. These include iontophoresis, pretreatment of skin with laser or ultrasound, and needle-free jet injection of local anesthetics. Protocols for placing topical anesthetics at triage also reduce negative impact on emergency department flow. Despite these advances, topical anesthetics are not routinely used in emergency departments for minor procedures. This article reviews available and upcoming topical anesthetic products, as well as adverse effects, and procedure and disease-specific uses of topical anesthesia.