polymer is preferably capable of absorbing a substantial amount of drug solution when applied as a coating on a medical device in accordance with the present invention the dry polymer is typically on the order of from about 1 to about 50 microns thick in the case of a balloon catheter the thickness is preferably about 1 to 10 microns thick and more preferably about 2 to 5 microns very thin polymer coatings e g of about 0 2 0 3 microns and much thicker coatings e g more than 10 microns are also possible it is also within the scope of the present invention to apply multiple layers of polymer coating onto a medical device such multiple layers are of the same or different polymer materials the polymer may be hydrophilic or hydrophobic and may be selected without limitation from polymers including for example polycarboxylic acids cellulosic polymers including cellulose acetate and cellulose nitrate gelatin polyvinylpyrrolidone cross linked polyvinylpyrrolidone polyanhydrides including maleic anhydride polymers polyamides polyvinyl alcohols copolymers of vinyl monomers such as eva polyvinyl ethers polyvinyl aromatics such as polystyrene and copolymers thereof with other vinyl monomers such as isobutylene isoprene and butadiene for example styrene isobutylene styrene sibs copolymers styrene isoprene styrene sis copolymers styrene butadiene styrene sbs copolymers polyethylene oxides glycosaminoglycans polysaccharides polyesters including polyethylene terephthalate polyacrylamides polyethers polyether sulfone polycarbonate polyalkylenes including polypropylene polyethylene and high molecular weight polyethylene halogenated polyalkylenes including polytetrafluoroethylene natural and synthetic rubbers including polyisoprene polybutadiene polyisobutylene and copolymers thereof with other vinyl monomers such as styrene polyurethanes polyorthoesters proteins polypeptides silicones siloxane polymers polylactic acid polyglycolic acid polycaprolactone.