PROBLEM TO BE SOLVED: To provide a method for producing a bioactive surface on an endoprosthesis or on a balloon of a balloon catheter.SOLUTION: The surface (15) of an endoprosthesis or the surface (4) of a balloon (3) is softened, and moistened with a solution (6) of an active ingredient (7), and the solvent (8) is separated from the active ingredient (7). In addition, a balloon (3) of a balloon catheter (1) is disclosed, which comprises an uncoated surface (4), wherein an unencapsulated active ingredient (7) is embedded at least partially into the material of the surface (4). Furthermore, a balloon catheter (1) is described, which comprises a balloon (3) according to the present invention. In addition, an endoprosthesis, particularly a polymer stent is described, which comprises an uncoated surface (15), wherein an active ingredient (7) is embedded at least partially into the material of the surface (15).
