In Vitro and In Vivo Evaluation of Diclofenac Sodium Gel Prepared with Cellulose Ether and Carbopol 934P

Purpose: To develop diclofenac sodium gel using high molecular weight hydroxypropyl ethylcellulose(HPMC) and Carbopol 934P for topical and systemic delivery. Methods: Diclofenac sodium gel was prepared with HPMC K100M and Carbopol 934P as gelling agents. The formulations were examined for pH, spreadability, consistency, viscosity, homogeneity, drug content and stability. In vitro drug release was evaluated using Franz diffusion cell. Carrageenan-induced rat paw oedema model was used for the evaluation of the anti-inflammatory activity of the gels. A commercial diclofenac sodium gel product was used as the reference drug. Results: Formulations containing glycerin as permeation enhancer gave drug release patterns comparable to that of the reference product. The drug content of F2, F5 and F9 was 99.81, 99.75 and 99.96 %, respectively. Accelerated stability results showed no significant variation in the appearance and drug release after storage for 3 months. Conclusion: Diclofenac sodium gel containing HPMC K100M and Carbopol 934P exhibited pronounced anti-inflammatory activity and could be further developed for topical and systemic delivery..