Enhanced Iontophoretic Permeation of Rizatriptan Benzoate from Thermo- reversible Gel Based System: Effect of Penetration Enhancers and Pulsed Current

formulation by using chemical penetration enhancers and to study the effect of pulsed current on permeation through guinea pig, Wistar rat and human cadaver skin. Modified Franz diffusion cell was used to study the in vitro permeation across various types of skin by iontophoresis. The thermo-reversible gel was prepared and optimized by cold method using poloxamer 407 as a gelling agent. Thermo-reversible gel with 20% w/v poloxamer 407 has suitable gelation temperature and viscosity for iontophoretic delivery of RZB. The highest permeation obtained was with iontophoresis in combination with 10% v/v PEG-400 as penetration enhancer. The permeation of RZB was significantly higher with pulsed current (1:1 as a ON: OFF ratio) at 0.5 mA/cm2 as a current density than direct continuous current. It was observed that highest permeation was obtained through the rat skin as compared to guinea pig skin, and the permeation through human epidermis was lowest. The study reveals that it is feasible to deliver RZB by iontophoresis in combination with penetration enhancer and pulsed current from Poloxamer thermo-reversible gel.