The invention relates to a cross-linked silyl-containing polymer that is used, together with a tackifying resin, to form an adhesive composition capable of storing and delivering a drug to the skin of a user. Typically the composition is formed into a patch which shows excellent adhesion to the skin even when drugs and other additives are dissolved into the composition. The polymer is a polycarbonate and the tackifying resin is preferably a mixture of styrene-acrylic resins, rosin ester resins or dicyclopentane-acrylic polymers. The drug could be an analgesic, a hormone or an anti-addiction drug such as nicotine.
