The invention relates to an oral dosage form, which is safeguarded against abuse and which has a controlled release of (1R, 2R)-3-(3-dimethylamino-1-ethyl-2-methyl-propyl)-phenol for a once daily administering. The invention is characterized in that the oral dosage form comprises the active ingredient and/or one or more pharmaceutically acceptable compounds (A) thereof, at least one synthetic and/or natural polymer (C), retarding adjuvants, optionally comprises additional physiologically compatible adjuvants (B), and optionally comprises a wax (D). The oral dosage form has a breaking resistance of at least 500 N, preferably at least 750 N. The dosage form contains at least one of the following abuse-preventing constituents (a)-(f)； (a) at least one substance that irritates the nasal and/or pharyngeal cavity； (b) at least one viscosity-increasing agent； (c) at least one antagonist for the active ingredient having an abuse potential； (d) at least one emetic； (e) at least one colorant serving as an aversive agent, and； (f) at least one bitter substance.
