Comparative Evaluation of Zidovudine Loaded Hydrogels and Emulgels

Zidovudine (AZT) is the widely used anti-retroviral drug associated with serious gastric side effects upon oral delivery also having short half life and poor partition coefficient. Upon oral administration it also undergoes first pass metabolism. Transdermal delivery of AZT encounters all the problems associated with oral route. In the present study we developed hydrogels as well as emugels loaded with AZT and investigated the ability of hydrogels as well as emulgels to deliver the AZT via transdermal route. All the gels were evaluated for their physical properties, drug content, viscosity, pH, spreadability and in vitro drug release. In vitro release pattern for all the formulations were found to be zero order diffusion controlled. All the formulations were found to be compatible with skin and stable as per ICH guidelines. Among all the formulations emulgels were found to be effective vehicles to deliver AZT because of the effective partition in both oil and aqueous phases.