Zonegran for the Treatment of Weight Gain Associated With Psychotropic Medication Use: A Placebo-Controlled Trial

Inclusion Criteria: * Are men or women, between the ages of 19 and 65, inclusive * Have a diagnosis of any type of bipolar disorder or any type of psychotic disorder based on structured diagnostic interview (MINI). * Are currently outpatients or inpatients and taking a neuroleptic or mood stabilizer medication (listed below) for the past 6 months, and on a stable dose for the past 2 months. * Have a body mass index \> 25. * No substance use disorder in the past 2 months (except for nicotine or caffeine). * Agree to not become pregnant during the study and agree to use an adequate method of birth control during the study such as a barrier method, hormonal contraceptive, or surgical sterilization (females only). All women of childbearing potential must have a negative pregnancy test before beginning study medication. * Are able to swallow the capsules whole * Are willing and able to follow Investigator instructions and study procedures, and report adverse events * Not currently actively suicidal or homicidal. * No use of topiramate within the last 6 months. * No medical contraindication to the use of zonisamide. List of medications for inclusion criterion #3: All conventional neuroleptics. All atypical neuroleptics except aripiprazole or ziprasidone. All forms of valproate. All forms of lithium. All forms of carbamazepine. Exclusion Criteria: * Clinically significant renal or hepatic disease. * History of acute intermittent porphyria, glucose-6phosphate dehydrogenase deficiency or hemolytic anemia. * Allergy to zonisamide or sulfonamides. * Have clinically unstable cardiovascular, hepatic, renal, gastrointestinal, pulmonary, metabolic, endocrine, or other systemic disease * Have laboratory test results that, in the opinion of the Investigator, are clinically significant abnormalities * Require treatment with any medication (e.g., carbonic anhydrase inhibitors) that might interact adversely with, or obscure, the action of the study drug * Are pregnant or lactating (females only) * Have a history of nephrolithiasis * Refuse to give informed consent * Have previously enrolled in this study or previously been treated with zonisamide