Home > General Info>About obesity If you have a Body Mass Index (BMI) of 30 or more with no obesity-related conditions or a BMI of 27 to 29.9 and two or more obesity-related conditions, ask your doctor about drug treatment for weight loss and weight maintenance. Drugs for treating obesity have had a bad track record. Amphetamines and the fen-phen combination produced serious side effects and were discontinued. However, the products on the market now have good safety records, and studies have shown them to be effective. But no products are 'magic bullets." Patients taking drugs still need to work on their diets and physical activity. Drug treatment should be used in combination with a healthy diet and physical activity. Your doctor may also suggest a combination of behavior therapy and drug therapy, which may improve your treatment outcome. Regularly follow-up visits to your doctor are recommended to monitor progress and to maintain safety of the drug's use. Weight loss drugs approved by the U.S. Food and Drug Administration (FDA) for treating obesity include: Orlistat (Xenical), Phentermine, and Sibutramine (Meridia). ◈ Orlistat (known as Xenical) works by blocking about 30% of dietary fat from being absorbed, ..and is the most recently approved weight loss drug. ◈ Phentermine (a generic drug) is an appetite suppressant that has been available for many years. ..It is half of the "fen-phen" combination that remains available for use. ..The use of phentermine alone has not been associated with the adverse health effects of .. the fenfluramine-phentermine combination. ◈ Sibutramine (known as Meridia) is an appetite suppressant approved for long-term use.