The present invention features a novel therapy for effecting weight loss which involves treating a subject with a sympathomimetic agent (e.g., phentermine or a phentermine-like drug) in combination with an anticonvulsant sulfamate derivative (e.g., topiramate) such that the subject experiences weight loss. The combination methods of the present invention also are effective against symptoms associated with Syndrome X. The invention also features pharmaceutical compositions and kits for use in the practice of these novel therapies.