LEP and Cognitive impairment: Despite the definite usefulness of lithium therapy in this disorder, this drug accompany with the important complication of weight gain and increase in body mass index and changes in leptin levels (Atmaca et al., 2002), abnormal state of metabolic status and impairment of fat profile (Livingstone & Rampes, 2006) and some degree of cognitive impairment (memory impairment) (Pachet & Wisniewski, 2003).