A Double-Blind, Randomized, Split-Face Comparison Trial on Topical Anesthetic Agents Prior to Fractional Skin Resurfacing

Lasers can be effectively utilized for facial rejuvenation, reduction of photoinduced rhytides, and dyschromia. Topical anesthetics are used to minimize the discomfort associated with laser induced thermal pain. There are currently several formulations of topical anesthesia. However, studies comparing the products are limited especially for the new formulations that claim increased efficacy and faster onset. LMX4 (Ferndale Laboratories, Ferndale, Michigan) is over the counter topical anesthesia. It is 4% lidocaine that has been formulated into multilamellar vesicles containing several lipid bilayers. This unique liposomal-based delivery system has been reported to deliver a greater concentration of drug. This results in a longer duration of activity and faster onset of action without requiring occlusion.4 Liposomes assist with drug penetration because the skin is lipid bilayer that can encapsulate the drug. BLT is a compounded topical anesthetic containing 20% benzocaine, 6% lidocaine, and 4% tetracaine. It is commonly prescribed as topical anesthesia. All BLT products will be compounded at the University Physicians Center Pharmacy to ensure safety and uniformity. Anecdotally, some physicians claim it is the topical anesthesia of choice prior to laser surgery. The objective of the study is to evaluate the clinical efficacy of topical anesthetic compounds prior to fractional skin resurfacing.