Second Generation antipsychotics, including olanzapine are commonly prescribed for the treatment of schizophrenia. Olanzapine is recognized for its superior therapeutic efficacy; however it may cause adverse effects such as weight gain. The underlying mechanisms responsible for this side effect have not been fully elucidated in basic research. In this study, we investigated metabolic profiles of olanzapine-treated rats, using long-term indirect calorimetry system. This system allowed us to assess several metabolic parameters. These included energy expenditure(EE), respiratory quotient(RQ), carbohydrate oxidation(CHO) , and fat oxidation(FO).
The results showed that olanzapine at 3 mg/kg once daily increased energy expenditure(EE) per body weight in rats. In addition, respiratory quotient(RQ) indicated high values.
These results suggest that olanzapine alter the metabolism of carbohydrates and lipids in rats, which may contribute to olanzapine-induced weight gain. The development of targeted interventions to mitigate the adverse effects associated with olanzapine treatment may be facilitated by an understanding of these mechanisms.