Development of Vaginal Tablet of Clotrimazole Prepared by Applying the Concept of Percolatio Threshold

Abstract

Clotrimazole is the drug of choice in the treatment of vulvovaginal candidiasis and belongs to biopharmaceutical classification system (BCS) class IIb. Therefore, it should be presented in appropriate form adopting a suitable formulation approach to ensure its fast and complete release in the vagina. Solid dispersion of clotrimazole was prepared using microcrystalline cellulose as a carrier material after confirming their miscibility into each other by the ‘melting point depression’ method. Vaginal tablets of the solid dispersion of clotrimazole were prepared by direct compression using co-processed crospovidone as a novel disintegrant (1.5% w/w) to ensure fast disintegration of the tablet. Co-processed crospovidone was selected as a novel disintegrant and its proportion in the formulation was decided by applying the concept of percolation threshold. The superior functionality of co-processed crospovidone as a disintegrant was because of its larger pore size i. e., 4.27Ao than the pore size of crospovidone 3.99Ao. The faster ingress of water through the larger pores leads to the fast disintegration of the tablet. Rapid release of the drug from the disintegrated tablet dosage form was confirmed by performing in-vitro antifungal studies. The statistical analysis of the data obtained after applying the student ‘t’ test indicated that there was a difference in the means of zone of inhibitions between the tablets of optimized composition and the tablets the plain clotrimazole at p less than 0.5.