It is intended to provide a novel preparation containing a substance selected from the group consisting of aminoalkoxybibenzyls, pharmaceutically acceptable salts thereof, esters thereof, solvates thereof, and hydrates thereof as an active ingredient. According to the invention, the novel preparation which contains a substance selected from the group consisting of aminoalkoxybibenzyls, pharmaceutically acceptable salts thereof, esters thereof, solvates thereof, and hydrates thereof as an active ingredient and achieves a sustained blood concentration can be provided.
