Body weight and leptin plasma levels during treatment with antipsychotic drugs

Objective: Leptin is produced by fat cells and is presumed to signal the si ze of the adipose tissue to the brain. The authors investigated whether ant ipsychotic drugs that often induce weight gain affect circulating levels of leptin. Method: Weight, body mass index, and leptin plasma level were meas ured weekly over 4 weeks in psychiatric inpatients who received clozapine ( N=11), olanzapine (N=8), haloperidol (N=13), or no psychopharmacological tr eatment (N=12). Results: In patients receiving clozapine or olanzapine, sig nificant increases in weight, body mass index, and leptin level were found, whereas these measures remained stable in patients who received haloperido l or no pharmacological treatment. Conclusions: Weight gain induced by cloz apine or olanzapine appears to be associated with an increase in leptin lev el that cannot be attributed to dietary changes upon hospitalization.