Provided are : a pharmaceutical for preventing and/or treating symptoms of depression, the pharmaceutical comprising (S)-norketamine or a pharmacologically acceptable salt thereof; a pharmaceutical composition for preventing and/or treating symptoms of depression, the composition containing (S)-norketamine or a pharmacologically acceptable salt thereof in an amount effective for alleviating symptoms of depression, and containing substantially no (R)-norketamine; a method for preventing and/or treating symptoms of depression, the method including administering the pharmaceutical or composition; and a use for (S)-norketamine in producing a pharmaceutical for preventing and/or treating symptoms of depression or a composition for preventing and/or treating symptoms of depression.