The present invention generally relates to pharmaceutical compositions comprising a dopamine agonist and sedative agent. In a preferred embodiment, the dopamine agonist is optically pure (S)-didesmethylsibutramine. In a preferred embodiment, the sedative agent is optically pure (S)-zopiclone or optically pure (S)—N-desmethylzopiclone. In a preferred embodiment, the dopamine agonist is optically pure (S)-didesmethylsibutramine; and the sedative agent is optically pure (S)-zopiclone or optically pure (S)—N-desmethylzopiclone. The pharmaceutical compositions of the invention are useful in the treatment of restless-leg syndrome and periodic-limb-movement disorder, as well as various sleep disorders. In addition, the present invention relates to a method of treating a patient suffering from restless-leg syndrome, periodic-limb-movement disorder, a sleep abnormality, or insomnia, comprising coadministering a therapeutically effective amount of a dopamine agonist and a therapeutically effective amount of a sedative agent. In a preferred embodiment, the dopamine agonist is optically pure (S)-didesmethylsibutramine. In a preferred embodiment, the sedative agent is optically pure (S)-zopiclone or optically pure (S)—N-desmethylzopiclone. In a preferred embodiment, the dopamine agonist is optically pure (S)-didesmethylsibutramine; and the sedative agent is optically pure (S)-zopiclone or optically pure (S)—N-desmethylzopiclone.