Background: Clinically severe obesity (CSO) is a surgically treated disease. The Roux-en-Y gastric bypass (RYGBP) has been used to treat patients with CSO and has resulted in an improvement in co-morbidities. We speculated that after a period of weight loss, patients would require less medication, resulting in cost-savings to both the patient and the insurance company, as well as an overall gain in health., Method: A retrospective study was performed which involved the first 100 patients who had undergone RYGBP at a community-teaching hospital. Analysis of the data was conducted by the Wilcoxon signed rank test. Results: 64 patients met our inclusion criteria and had adequate follow-up data available. The mean BMI was 57 kg/m(2) (range 36.6-85.4 kg/m(2)), the female to male ratio was 4:1 (51:13), and the mean age was 44 years (range 27-64). The average monthly medication expenditure was reduced from $317 (SEM 47.25, range $23.12-$1801.19) preoperatively, to $135 (SEM 35.35, range $0.00-$1122.72) postoperatively. This reduction is significant (P<0.01). Conclusion: Weight loss after RYGBP leads to a significant reduction in medication expenses. These medication savings offset the costs of the initial procedure and represent permanent financial savings for the patient and society.