Self-warming lidocaine/tetracaine patch effectively and safely induces local anesthesia during minor dermatologic procedures.

BACKGROUND: Dermatologic procedures often cause some degree of pain. A self-warming patch containing lidocaine and tetracaine (L/T) was developed to provide topical local anesthesia prior to painful procedures.

OBJECTIVES: To evaluate the safety and efficacy of a self-warming L/T patch to provide anesthesia in adult patients undergoing minor dermatologic procedures.

METHODS: An active or placebo study drug was placed on adults 30 minutes prior to minor dermatologic surgical procedures in a prospectively randomized, double-blinded manner. Subcutaneous lidocaine injection was available during the procedure as a rescue medication if requested by the subject. Immediately following the procedure, the subjects, the investigator, and an independent observer rated pain intensity and adverse events were recorded.

RESULTS: Patient-reported pain intensity was significantly lower in the L/T patch group (p<.001). Investigators and an independent observer rated the pain in the L/T patch group to be less than in the placebo patch group (p = .004 and p<.001, respectively). Forty-nine percent of patients in the placebo group required rescue subcutaneous lidocaine compared with 22% in the L/T patch study group (p = .008). One patient in the L/T patch group reported a transient moderate burning sensation.

CONCLUSION: The self-warming L/T patch was effective in providing clinically useful local anesthesia for minor dermatologic procedures in adult patients.