MERIDIA® (sibutramine hydrochloride monohydrate) Capsules is indicated for the management of obesity, including weight loss and maintenance of weight loss, and should be used in conjunction with a reduced calorie diet. MERIDIA is recommended for obese patients with an initial body mass index 30 kg/m2, or 27 kg/m2 in the presence of other risk factors (e.g., hypertension, diabetes, dyslipidemia).
Below is a chart of Body Mass Index (BMI Q&A here) based on various heights and weights. BMI is calculated by taking the patient’s weight, in kg, and dividing by the patient’s height, in meters, squared. Metric conversions are as follows:

pounds 2.2 = kg;
inches x 0.0254 = meters.

source: FDA (pdf file)

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