Comparative efficiency of propylene glycol and polyethylene glycol in enhancing percutaneous absorption and release of a drug through silicone membrane and rat skin

The present study describes comparative efficiency of propylene glycol (pg) and polyethylene glycol (peg) in enhancing percutaneous absorption and release of cetirizine hydrochloride (a model drug) through silicone membrane and rat skin. various gel formulations of cetirizine hcl were prepared and optimized by using response surface methodology containing different ratios of pg(x1) and peg(x2) taken as two independent variables whereas cumulative amount of cetirizine hcl was used to calculate dependent (response) variables (y1 - y7). the results showed that independent variables had remarkable effects (p < 0.05) on dependant variables. the cetirizine hcl is freely soluble in water and pbs. the value of partition coefficient (ko/w) calculated is 1.91±0.03. formulations g1-g9,g11 and g13 showed good homogeneity while formulations g10 and g12 showed comparatively good homogeneity. formulations g2-g9 showed spreadability in a range of 3.2-4.6 cm while formulations g1 and g10- g13 showed comparatively less spreadability i.e. 2.0-2.3 cm. the ph values of the prepared gels were measured at 25±1°c which ranged between 5.8-7.2. the viscosity of all prepared gels was determined and they were found within the limits i.e. 130-138 cps × 103. primary skin irritation test was performed for optimized gels i.e. g4 and g8 on 11 volunteers and found no irritation or lesions. g4 and g8 possess greater values of flux er .the values of tlag of these gels were minimum. therefore g4 and g8 pass across the membrane in less time in comparison with other gels. values of kp and i/r were also more prominent in g4 and g8. it was concluded that pg and peg can be successfully used in combination as permeation enhancers for transdermal delivery of cetirizine hcl. © copyright 2014 zoological society of pakistan.