Piloting a New Approach to the Treatment of Obesity Using Dexamphetamine

Background and aims: There is a clear need for a new approach to the treatment of obesity, which is inexpensive and is effective for establishing lifestyle change. We conducted a pilot study to evaluate whether dexamphetamine can be used safely, combined with diet and exercise, for treating obesity. Our ultimate aim is to develop a 6-month treatment program for establishing the lifestyle changes necessary for weight control, utilizing dexamphetamine for its psychotropic effect on motivation. We viewed the anorexigenic effect as an additional advantage for promoting initial weight loss. Methods: Obese adults were treated with dexamphetamine for 6 months (maximum of 30 mg twice daily), diet, and exercise. Weight, electrocardiogram, echocardiogram, and blood pressure were monitored. Results: Twelve out of 14 completed 6 months treatment. Weight loss by intention to treat was 10.6 kg (95% CI 5.8–15.5, p < 0.001). The mean weight gain in the 6 months after ceasing dexamphetamine was 4.5 kg (95% CI 1.9–7.2, p = 0.003), leaving a mean weight loss at 12 months from baseline of 7.0 kg (95% CI −13.4 to −0.6, p = 0.03). All reported favorable increases in energy and alertness. Dose-limiting symptoms were mood changes (2) and insomnia (2). None had drug craving on ceasing dexamphetamine, and there were no cardiac complications. Among the seven women, there was a significant correlation for those who lost most weight on treatment to have the least regain in the following 6 months (r = 0.88, p = 0.009). Conclusion: Our treatment with dexamphetamine, diet, and exercise was well tolerated and effective for initial weight loss. Future research will focus on identifying baseline predictive variables associated with long-term weight control.