Stability Evaluation of Compounded Benzocaine, Lidocaine, and Tetracaine in VersaPro™ Cream Base.

Compounded Benzocaine (20%), Lidocaine (6%), and Tetracaine (4%) in VersaPro™ Cream Base was studied to evaluate the chemical, physical, and microbial stability over a 180-day period. Preparations were stored in ambient conditions in tightly closed, light-resistant, metered-dose plastic containers. An HPLC assay was developed and validated to assess chemical stability, while physical stability was assessed by observing organoleptic characteristics and measuring pH levels. Antimicrobial effectiveness testing was conducted according to USP <51> at the final stability time point. The results indicate that combined Benzocaine (20%), Lidocaine (6%), and Tetracaine (4%) compounded in VersaPro™ Cream Base was stable for the duration of the study and may be assigned an extended beyond-use-date of 180 days under the examined conditions.