The Evaluation of Concentration - In-Vitro Release Relationship for Topical Semisolid Formulations of Sodium Cromoglycate

Purpose. The aim of the study was to evaluate the concentration - in-vitro release relationship for topical semisolid formulations of sodium cromoglycate. Materials / Methods. According to usual pharmaceutical compounding practice, commercially available cosmetic emulsions were used as vehicles for topical semisolid dosage forms containing 0.5, 2, 4 and 10% disodium cromoglycate (CS). The in-vitro release profiles and structural parameters of the resulting formulations was evaluated in a correlated manner, in order to reveal potential differences in the in-vivo performance. Results. Depending on the hydro-lipophilic characteristics of the vehicle and on the quantity of drug dissolved or dispersed, the structure and the release kinetics are distinct. Conclusions. The results suggested that current lack of an unitary approach for the compounding of semisolid dosage forms of CS, resulting from the lack of widely available, standardized dosage form could be a reasonable explanation for the apparent discrepancy in the reports of clinical outcome after topical administration.