Drug treatment of obesity

Drugs to treat obesity can be divided into three groups: those which reduce food intake, those which alter metabolism and those which increase thermogenesis. Monoamines acting on noradrenergic receptors, serotonin receptors, dopamine receptors and histamine receptors can reduce food intake. A number of peptides also affect food intake. The noradrenergic drugs phentermine, diethylpropion, mazindol benzphetamine and phendimetrazine are approved only for short-term use. Sibutramine, a norepinephrine–serotonin re-uptake inhibitor, is approved for long-term use. Orlistat inhibits pancreatic lipase and can block 30% of triglyceride hydrolysis in subjects eating a 30% fat diet. The only thermogenic drug combination that has been tested is ephedrine and caffeine, but this treatment has not been approved by regulating agencies. Leptin is currently in clinical trials and other drugs that may modulate peptide-feeding systems are being developed.