Preparation of celecoxib solid dispersions for dermal application: in vitro characterization and skin irritation test

The purpose of this work was to improve the dissolution and skin permeability characterestics of celecoxib. Solid dispersions (SDs) of celecoxib were prepared using PEG 4000, PVP K30 and HPβCD by the kneading method. The dispersions were characterized by, (DSC), (XRD) and in vitro drug dissolution. The solubility and dissolution of SDs were markedly increased as compared to plain drug. The kneaded dispersions showing high dissolution were incorporated in an o/w cream and evaluated for in vitro drug permeation through rabbit skin. The permeation rate of celecoxib were significantly increased in the case of SDs when compared to plain drug. The anti-inflammatory effect of celecoxib-PVP K30 cream was more effective in inhibiting rat paw edema when compared to celecoxib cream. Skin irritancy and histopathological investigation of rat skin revealed its safety thus confirming the advantage of improved pharmacological activity and safety of celecoxib when administered topically as solid dispersion with PVPK30.