Sibutramine (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.

Pharmacokinetics

---

Sibutramine is well absorbed from the GI-Tract (77%), but undergoes a considerable first-pass metabolism reducing its bioavailability. The drug itself reaches its peak plasma level after 1 hour and has also a halflife of 1 hour. Sibutramine is metabolized by cytochrome-P450-isoenzyme CYP3A4 resulting in 2 active primary and secondary amines (called active metabolites 1 and 2) with halflives of 14 and 16 hours, respectively. Peak plasma concentrations of active metabolites 1 and 2 are reached after 3 to 4 hours. The following metabolic pathway mainly results in two inactive conjugated and hydroxylated metabolites (called metabolites 5 and 6). Metabolites 5 and 6 are mainly excreted in the urine.

Pharmacological aspects

---

Sibutramine is a neurotransmitter reuptake inhibitor that helps enhance satiety by inhibiting the reuptake of serotonin (by 73%), norepinephrine (by 54%), and dopamine (by 16%); as such it is a satiety enhancer (i.e. it enhances satiety). Despite its actions upon the aforementioned neurotransmitters, sibutramine has never demonstrated any antidepressant properties. It was approved by the Food and Drug Administration (FDA) in November 1997FDA 1997 approval. for the treatment of obesity.

More on [ Sibutramine ]

Subscribe to Sibutramine RSS feed