The present invention relates to an abuse-proofed oral dosage form with controlled release of (1R,2R)-3-(3-dimethylamino-1-ethyl-2-methyl-propyl)phenol for once daily administration, which comprises the active ingredient and/or one or more of the pharmaceutically acceptable salts thereof (A), at least one synthetic or natural polymer (C), delayed-release auxiliary substances, optionally physiologically acceptable auxiliary substances (B) and optionally a wax (D), component (C) or (D) in each case exhibiting a breaking strength of at least 500 N, preferably of at least 1000 N.