In adolescents, there is an epidemic of being overweight or obese. Sibutramine has been shown to cause sustained loss of weight in adults. in a study based in Mexico City, adolescents with a BMI of 35/36 kg/m(2), who were put on a hypocaloric diet and undertook physical activity, lost 4.3 kg in 6 months, and this loss was increased to 7.3 kg by sibutramine. Similarly, in a study based in the US, there was a loss of 1.9 kg in the placebo group of obese adolescents with a hypocaloric diet and increased physical activity at the end of 12 months, and this was increased to 6.5 kg in the sibutramine group. Sibutramine has a slight tendency to increase blood pressure and heart rate, and seems to be more effective than orlistat in causing weight loss in adolescents. However, orlistat does not have negative effects on blood pressure. Long-term follow-up studies of sibutramine in adolescents are needed to determine whether the weight loss is maintained, and whether the weight loss translates into better clinical outcomes.