Effect of vehicles and pressure sensitive adhesives on the permeation of tacrine across hairless mouse skin

The purpose of this study was to investigate the feasibility of developing transdermal drug delivery (TDD) system for tacrine used for treating the symptoms of Alzheimer's disease. The effects of various vehicles on the percutaneous absorption of tacrine in solution formulation and in pressure sensitive adhesive (PSA) matrix across the hairless mouse skin were evaluated using flow-through diffusion cell system at 37 degrees C. The permeation profiles of tacrine from solutions were different depending on vehicles used. The flux of tacrine increased significantly as its concentration in the solutions increased. The permeation rate of tacrine was higher in acrylic adhesives with hydroxyl functional group and without functional group than in polyisobutylene adhesive matrix. Incorporation of vehicles into the acrylic adhesive matrix significantly enhanced the permeation rate and shortened the lag time of tacrine. The maximum flux obtained from pressure sensitive adhesive matrix seemed to be high enough to obtain therapeutic effect.