Rimonabant is a selective CB1 receptor inverse agonist with a Ki of 1.8 nM and no activity at CB2 receptors. Rimonobant also acts as a µ-opioid receptor antagonist with a Ki of 652 nM. Rimonabant reduces the overactivity of the endocannabinoid system, improving lipid and glucose metabolism and regulating energy balance. In animal sudies, it reduces food intake and body weight in orally dosed non-obese Wistar rats and has a positive role in reducing hunger, caloric intake, and body weight, and in increasing satiety. In humans, rimonabant initially appeared to be effective for treatment of obesity and smoking cessation but was withdrawn from the market due to having the potential to cause severe psychiatric side effects.
