Described herein are methods of treating narcolepsy with cataplexy, comprising administering reboxetine (including esreboxetine) to a human being in need thereof. Reboxetine (including esreboxetine) may also be used in the manufacture of a medicament for the treatment of narcolepsy with cataplexy. Also disclosed herein are kits comprising a pharmaceutical composition comprising reboxetine (including esreboxetine) and instructions to use the pharmaceutical composition to treat narcolepsy with cataplexy in a human being.