摘要 |
The process results in an adhesive plaster for the transdermal adminstration of pharmaceutical, in particular heat-sensitive, active substances, composed of an adhesive layer, a backing layer, a matrix layer containing the active substances, and a protective layer. The flux of active substance release is controlled by its diffusion from the matrix layer. The latter is produced by the hot melt method, by mixing an ethylene/vinyl acetate copolymer and an involatile, hydrophobic excipient which is miscible with the latter, is compatible with the active substance and is tolerated by the skin, for example isopropyl myristate or a triglyceride, at the melting point of the mixture, and incorporation therein of a solution or dispersion of the active substance in a small amount of the same excipient.
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