This is a 17-week, parallel group, placebo-controlled, randomized, double-blind, flexible-dose, single-center study. It begins with a 1 to 2 week screening period during which there will be washout of other medications and evaluation of protocol-specified criteria. The screening period will consist of at least two visits, which will include the initial screening visit and the baseline (week 1) visit. The treatment period follows the screening period and will last 16 weeks. Once a subject enters the treatment phase (after randomization) the dosage of study medication will be 25 mg/qHS (or one placebo tablet at night) for 14 days. On day 14 (visit 2 or the beginning of week 3), the dosage will be increased, as tolerated, to 25 mg b.i.d. On day 28 (visit 4 or in the beginning of week 5), the dosage will be increased, as tolerated, to 50 mg b.i.d. On day 35 (visit 5 or the beginning of week 6), the dosage will be increased, as tolerated, to 100 mg b.i.d. The dosage may be decreased at any time because of side effects. If the patient prefers, he or she may take all of his or her daily dose of medication in the morning or evening. If no response or an inadequate response (< 50% reduction in binge eating episodes compared with baseline) is evident by week 6 (visit 6), study medication may be increased to 150 mg b.i.d. If no response or an inadequate response is evident by week 8 (visit 7), study medication may be increased to 200 mg b.i.d. During weeks 12 through 16 (maintenance period) the dosage will not be changed unless a medical reason (e.g., adverse effect) requires such a change. The minimum dosage allowed will be 50 mg/day and the maximum dosage allowed will be 400 mg/day. The 16-week treatment period will be followed by medication discontinuation and evaluation 1 week after medication discontinuation (week 17). Efficacy and safety evaluations will be done at each visit starting with the baseline visit through week 17 (baseline, weeks 1, 2, 3, 4, 5, 6, 8, 10, 12, 14, 16).