and which should be physically and chemically compatible with thiamine and any carriers vehicles or other additives that are present examples of suitable adhesive materials include but are not limited to the following polyethylenes polysiloxanes polyisobutylenes polyacrylates polyacrylamides polyurethanes plasticized ethylene vinyl acetate copolymers and tacky rubbers such as polyisobutene polybutadiene polystyrene isoprene copolymers polystyrene butadiene copolymers and neoprene polychloroprene preferred adhesives are polyisobutylenes and polyacrylates during storage and prior to use the structure includes a release liner immediately prior to use this layer is removed from the device so that the system may be affixed to the skin the release liner should be made from a thiamine vehicle impermeable material and is a disposable element which serves only to protect the device prior to application typically the release liner is formed from a material impermeable to thiamine and which is easily stripped from the transdermal patch prior to use the thiamine reservoir and skin contact adhesive may be present as separate and distinct layers with the adhesive underlying the reservoir in such a case the reservoir may be a polymeric matrix as described above alternatively the reservoir may be comprised of a liquid or semisolid formulation contained in a closed compartment or u201c pouch u201d or may be a hydrogel reservoir or may take some other form hydrogels may be comprised of crosslinked hydrophilic polymers such as a polyurethane a polyvinyl alcohol a polyacrylic acid a polyoxyethylene a polyvinylpyrrolidone a polyhydroxyethyl methacrylate polyhema or a copolymer or mixture thereof particularly preferred hydrophilic polymers are copolymers of hema and polyvinylpyrrolidone additional.