Analgesic effect of topical lidocaine is enhanced by cold atmospheric plasma pretreatment in facial CO2 laser treatments

Background Topical anesthesia is widely used in many dermatological and cosmetic procedures. Nevertheless, the stratum corneum serves as the skin barrier, impedes the transdermal drug delivery greatly, and results in insufficient analgesia. Cold atmospheric plasma (CAP) has been researched as a transdermal drug delivery promoter with ex vivo experiments for a few years, while clinical trials are scarce. Aims To assess the efficacy and safety of CAP as a pretreatment to improve the transdermal absorption of topical anesthetic cream before the CO2 laser treatment for postacne scars in the human body. Patients/Methods Twenty patients, seeking full facial laser treatment for atrophic acne scars, underwent a randomized split-face study. One side of the face was pretreated by CAP before topical anesthetic cream was applied, and the other side was applied with topical anesthetic cream only as control. After that, the subjects went through full-face fractional CO2 laser treatment of postacne scars. They were asked to score the pain on a visual analogue scale (VAS) after the laser treatment to measure the anesthesia effects which indicates the transdermal absorption of the cream. Possible adverse effects of the plasma were recorded during the pretreatment including associated pain, heat, erythema, and edema. Results The VAS score of the treated side was statistically lower (5.1 +/- 2.1) compared with the nontreated side (6.3 +/- 1.9), with a mean difference of 1.3 (95% confidence interval [CI], 0.6-1.9; P < .0001). No severe adverse event was reported, and all the disturbing sensations and symptoms (pain, heat, and edema) were evaluated as mild with no mean score surpassing 4.0. Conclusion Plasma pretreatment of 5 minutes before topical anesthetic cream application gives significant pain reduction during the laser procedures, showing the potential effects of CAP on promoting transdermal drug delivery, with no obvious adverse effects reported.

Automated summary

The study found that pre-treatment with cold atmospheric plasma (CAP) for 5 minutes before applying topical anesthetic cream significantly improved the transdermal absorption of the cream and reduced pain during CO2 laser treatment for postacne scars. No severe adverse effects were reported, indicating the potential of CAP in promoting transdermal drug delivery.