Development and evaluation of occlusive systems employing polyvinyl alcohol for transdermal delivery of sumatriptan succinate

The aim of the present study was to develop a sumatriptan succinate transdermal system for applying migraine treatments efficiently and easily. For this system polyvinyl alcohol was employed as a matrix and Azone (R) was added as a permeability enhancer. The physical characteristics, mechanical properties, and in vivo bioadhesion of the systems were evaluated, as was in vitro permeation across porcine skin. A uniform distribution of the drug in the matrix was observed, and moisture uptake values were constant. With regard to mechanical parameters, occlusive layer inclusion made the system more resistant, and no significant differences were detected with respect to other systems. Although Azone (R) reduced the bioadhesivity of the systems, adherence to skin was maintained 24 h after application. Permeation studies showed that the systems formulated with Azone (R) provided the highest permeability profiles for sumatriptan succinate.