The protocol will begin with the administration of a structured diagnostic interview, the Structured Clinical Interview for DSM IV Diagnosis (SCID), and two depression rating scales, the Montgomery Asburg Depression Rating Scale (MADRS) and the Hamilton Rating Scale (HRS). Two tubes of blood will be drawn, one for erythrocyte EFA concentration determination and the other for quantification of inflammatory markers (c-reactive protein). Subjects will then be supplied with a one-month supply of escitalopram (Lexapro) with instructions to take one 10mg capsule each morning. Return visits at two weeks and four weeks will be scheduled and subjects will be instructed to return with any remaining medication.