How long do I need to take Alli?

A weight-loss plan with diet, exercise and drug therapy is generally considered successful if you lose about 1 pound (0.5 kilogram) a week during the first month and have lost 5 percent or more of the pre-treatment body weight within one year.

If the treatment is successful, you are more likely to keep weight off or lose more weight if you continue with the diet, exercise and drug treatment plan.

Most weight loss with the medication occurs within the first few months. If you have adhered to the diet and exercise plan and have not lost at least 5 percent of your initial body weight within a few months, continuing the medication may be of little benefit.

If you haven't lost 5 percent of your body weight within a year on the plan, discontinuing the drug would be a reasonable choice. The risks, side effects and cost associated with taking the medication likely override any potential benefit.