FORMULATION, CHARACTERIZATION AND EVALUATION OF SOLID DISPERSION FOR CNS DRUG LOADED IN TRANSDERMAL PATCH

Bromocriptine Mesylate (BM) solid dispersion (SD) was formulated and loaded into matrix type transdermal patch, optimized and characterized. BM, an anti-Parkinson’s agent, belonging to BCS Class II, has low aqueous solubility and high permeability. Solubility and bioavailability was enhanced by SDs using Hydroxy propyl beta cyclodextrin (HP-b-C) and Hydroxy propyl cellulose (HPC), by Solvent evaporation and Kneading method. The SD was selected based on %yield, %drug content and in vitro dissolution data. The SD prepared by kneading method using combination of 2 carriers in a drug carrier ratio of 1: 0.5 :3 (F4), exhibited highest percentage yield of 97.640 ± 0.7692%, percentage drug content of 98.770 ± 0.8129 % and in vitro release 98.85 % in 60 mins. Hence, F4 was used. Concentration of HPMC K4M, Eudragit RL 100 and Propylene glycol were selected as independent variables for design of experiment (DoE) using 23 Full factorial design. A formula for 8 runs was generated, and formulated. Diffusion study and folding endurance were selected as dependent variables. Based on response data, a formula was generated for the optimized transdermal patch (E9) and evaluated for thickness, weight variation, %drug content, %elongation, folding endurance, surface pH, in-vitro diffusion study, ex-vivo permeation study and skin irritancy study. BM-SD transdermal patch was successfully developed with improved dissolution profile, avoidance of extensive firstpass metabolism, improved patient compliance, effective and safe for use.