MERIDIA (sibutramine hydrochloride monohydrate) is an orally administered prescription medicine that may help obese people lose weight and keep weight off. Meridia may help with weight loss because it affects areas of the brain that control hunger. You should use Meridia with a low calorie diet.
Each MERIDIA capsule contains 5 mg, 10 mg, and 15 mg of sibutramine hydrochloride monohydrate. It also contains other inactive ingredients. Sibutramine hydrochloride monohydrate is a white to cream crystalline powder.

source partially: FDA (pdf file)

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