This study is a 13 week clinical trial. During the 13 weeks participants receive placebo, ondansetron and topiramate alone or in combination. During the 13 weeks participants come to an outpatient clinic to receive the study medication, physical checks, and cognitive behavioral therapy. The duration of the weekly visit is 3 hours. There is a 1, 2, and 3 month post-study follow up visit. Screening for this study is initially done over the telephone and takes 15-20 minutes. If there is nothing found to make someone ineligible to participate, they come to the out-patient clinic for a more thorough in-clinic screening.