Preparation and Clinical Evaluation of Lidocaine Stick for Pinpoint Anesthesia

Abstract

Resembling lipstick,Lidocaine Stick (LS) is used for pinpoint anesthesia of the skin prior to invasive procedures in dermatology or plastic surgery treatments,and has been shown to produce a quick and sustained anesthetic effect.We designed a formula and preparation method for LS,and evaluated its anesthetic effect by conducting a prick test in volunteers and a clinical study in patients undergoing pimple excision.We were able to design a surfactant-containing oily formulation for LS and a preparation method for it.
The results of the prick test indicated that the anesthetic effect of a 60% LS was comparable to that of a commercially available tape preparation containing the same volume of lidocaine.In the clinical study on patients undergoing pimple excision,the 60% LS produced an anesthesia rate of 65.5%.Furthermore in a questionnaire survey,both volunteers and patients responded favorably with regard to the smoothness and ease of use of the 60% LS.