Development and pre-clinical study of anti-allergic cream containing dexamethasone and chlorpheniramine

Objectives: In this study, we aimed to develop and optimize the anti-allergic cream containing dexamethasone and chlorpheniramine using the design of experiments (DoE) method. The optimized product was investigated the physicochemical properties and in vivo therapeutic effects in rabbits.
Materials and Methods: The creams were formulated by the simple mixing process, which was optimized by the Design Expert software. The products were then evaluated the properties such as pH, skin diffusion profile, short-term stability, qualitative, and assay, using the newly validated UV-Vis spectrophotoscopy quantitative method. In vivo efficacy test in rabbits of the best products were compared with the marketed Phenergan® (promethazine 2%).
Results: The UV-Vis method to simultaneously determine the amount of both dexamethasone and chlorpheniramine was successfully developed and validated. Using DoE method, it was clear that the release profile of dexamethasone was depended on the amount of sodium lauryl sulfate, propylene glycol, and DMSO. Whereas, only DMSO affected the release pattern of chlorpheniramine. Also, the best formulation was optimized by the software. The product showed acceptable parameters in pH (5.7 ± 0.1), short-term stability in 10 days, skin diffusion profiles of 20.47 ± 1.25% and 4.92 ± 0.42%, after 40 minutes, for dexamethasone and chlorpheniramine, respectively. In addition, the product demonstrated no observable inflammatory response in experimental animals. Also, it illustrated 2-fold better anti-allergic efficacy than the marketed product (i.e., 27.2 compared to 43.4 minutes in the recovery time).
Conclusion: We were successful in developing and optimizing the anti-allergic cream containing dexamethasone and chlorpheniramine. The best product satisfied all required parameters. Interestingly, our product showed higher efficacy than the Phenergan®. These results can be a background for further study in clinical trials.