Abuse-proof dosage form

An abuse-proofed dosage form thermoformed by extrusion without discoloration comprising one or more active ingredients with abuse potential (A), optionally physiologically acceptable auxiliary substances (B), at least one synthetic or natural polymer (C) and optionally at least one wax (D), wherein the dosage form exhibits a breaking strength of at least 500 N, the one or more active ingredients with abuse potential (A) are selected from the group consisting of oxymorphone and physiologically acceptable compounds and derivatives thereof, and the polymer (C) comprises polyethylene oxide having a molecular weight of at least 0.5 million g/mol.