Assessment of clinical efficacy of lidocaine/tetracaine 7%/7% peel cream in fractional microablative laser procedure-associated pain for facial skin aging treatment. A randomized, controlled, single-blind trial.

Abstract

Lidocaine/tetracaine 7%/7% peel cream (L/T-pC) is very effective in reducing pain in several dermatological procedures, such as hair or tattoo laser removal or conventional photodynamic therapy associated pain. Fractional laser resurfacing (FLR) is an effective treatment strategy for facial skin aging. The main drawback of FLR is the procedure-associated pain. So far, no controlled data are available regarding the efficacy of L/T-pC in reducing pain during a full-facial microablative FLR session in subjects with facial skin aging. To assess the clinical efficacy of L/T-pC in reducing pain during microablative FLR treatment in subjects with facial skin aging. We conducted a prospective, randomized, parallel-group, controlled, single-blind trial, performed in out-patients attending to a Laser Clinic for facial skin aging treatment. A total of 30 subjects (4men, 26 women; mean age 42±10years; range 28-57) with mild to moderate facial skin aging (Glogau score ≥2), suitable for FLR treatment, were enrolled after their written informed consent. Participants were randomized to L/T-pC application (45min before the laser treatment with the removal of the cream just before the starting of laser session) (n=20) or to control (emollient cream; n=10). FLR was performing using a fractional microablative CO2 laser (Smartxide DOT 2 Deka) using a pulse power of 18W (range 15-20) and pulse duration of 1.5msec. The primary endpoint was the comparison of the mean visual analogue score (VAS) values between the two groups using a 10-cm scale (0=no pain; 10: the most severe pain). The VAS score was measured just after the FLR session. Effective anesthesia (percentage of subjects with a VAS score ≤3) and the assessment of local tolerability and safety of the peel cream were the secondary trial endpoints. All the enrolled subjects concluded the trial. In the L/T-pC group, the VAS mean score was 3.0±1.2. In the control group, the VAS mean score was 8.6±0.5, representing a 65% reduction of the VAS score in the active treated group vs. controls. The difference between the two groups was statistically significant (p=0.0001; Mann-Whitney test) with an absolute difference of -5±0.4cm; 95%CI of the difference: from -4.6 to -6.4cm). Adequate anesthesia (VAS score≤3) was reported in 80% of subjects in the active group vs. 0% in the control arm. The cream was very well tolerated. One subject in the active group manifested moderate/severe edema in the cream application area, subsiding in 6h. No other side effects were reported. The application of L/T pC 7%/7% peel cream before a fractional laser resurfacing session significantly reduced the procedure-associated pain with good tolerability and safety profile.