Thermoplastic polyurethanes containing active substances

A method of producing a thermoplastically processable polyurethanes which contain active ingredients by the reaction of the polyurethane-forming components consisting essentially of

• A) an organic diisocyanate,
• B) a linear hydroxy-terminated polyol having a molecular weight of 500 to 10,000, and
• C) chain extenders having a molecular weight of 60 to 500, and adding during the reaction of A), B) and C),
• D) 0.01 to 10% by weight, with respect to the total amount of starting materials, of a pharmacologically active substance,
• wherein the molar ratio of the NCO groups in A) to the groups in B) and C) which are reactive towards isocyanate is 0.9 to 1.2 and the molar ratio of B) to C) is 1:1 to 1:12 and the molar ratio of A) to B) is 1.2:1 to 30:1.