The second generation antipsychotic agents, although exhibit superior safety profile, is associated with metabolic adverse effects including weight gain, diabetes mellitus and hyperlipidaemia. These adverse effects are not only the risk factors for cardiovascular disease and diabetes mellitus but may also impair patient’s adherence to treatment. However, different member of second generation antipsychotics differ in their extent of metabolic adverse effects. The aim of the study was to evaluate the association between olanzapine, risperidone or quetiapine treatment and body mass index, blood pressure, diabetes mellitus and hyperlipidaemia in patients with Schizophrenia and Bipolar Disorder. Forty-four cases of Schizophrenia and Bipolar Disorder diagnosed with DSM-IV criteria were selected according to inclusion and exclusion criteria.