ABSTRACT

The ainı of this studv w as to evaluate the permeatioıı enhancing effect of cosolvents on transdermal gel formulation ofTolterodine Tartrate (TT) ıısing experimental design techmque. The two factors chosen for Taguchi robııst design were the concentrations of ethanol and propylene glycol. The influence of cosolvents on the invitro penetration of TT through a synthetic membrane and abdominal rat skin from carbopol gels were investigated ıısing Keshary-chein type diffusion cells. Penetration through the synthetic membrane was w eli described bv the Higuchi model where as when ıısing rat skin, the penetration rate w as controlled bv the membrane(skin). The permeatioıı rate ofTT signifıcantlv increased in proportioıı to the ethanol and propylene glycol concentration showing cosolvent action. In conclusion, a transdermal TT gel was formulated successfully ıısing the techniqııe of Taguchi robııst design and these results were usefııl in fınding the optimum formulation for transdermal drug release. The optimized ratios of cosolvents were ethanol (60%) and propylene glycol (10%).