Funding not secured

The purpose of this research study is to test which topical anesthesia: LMX4 (Lidocaine 4%) or BLT (Benzocaine 20%, Lidocaine 6%, and Tetracaine 4%) is more effective in reducing discomfort during treatment with the Fraxel DUAL 1550/1927 (Solta Medical, Hayward, CA). No studies have been done on the effectiveness of LMX4 versus BLT using the Fraxel DUAL, although individually LMX4, BLT, and the Fraxel DUAL have been studied extensively.

The hypothesis is that there will be no clinical difference between the two topical anesthetics.

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.

Inclusion Criteria:

• At least 28 subjects will be included in this study.
• Subjects capable of giving informed consent.
• Patients 18 years of age and older will be included in this study.
• Any patient seeking Fraxel DUAL1550/1927 (Solta Medical) treatment on the face for rhytids, photoaging, hyperpigmentation, and acne scarring at the Hershey Medical Center dermatology clinics will be asked to participate.

Exclusion Criteria:

• Age <18
• Allergy to lidocaine or tetracaine
• Women who are pregnant or breast-feeding
• Patients with cardiac or respiratory disease, seizure disorders, or neuropathy
• Patients currently taking anxiolytics and opiates