Sibutramine (trade name Meridia® in the USA, Reductil® in Europe), usually as sibutramide hydrochloride monohydrate, is an orally administered agent for the treatment of obesity. It is a centrally acting stimulant chemically related to amphetamine, methamphetamine, and phentermine (one of the drugs in the Fen-Phen combination). Sibutramine is classified as a Schedule IV controlled substance in the United States.