The goal of this study was to investigate the role of sympathetic-adrenal medullary (SAM) and hy0pothalamo-pituitary-adrenal (HPA) systems in mediating the addictive effects of cocaine. A toal of 6 male subjects were enrolled for this 5 day inpatient study. Subjects were assigned to either cocaine (32mg /70kg iv) or placebo (saline iv) treatment during the first experimental sessions and were crossed over to the alternative treatment during the second experimental session. Endpoints that were followed during the experimental sessions included neuroendocrine (serum epinephrine, norepinephrine and cortisol levels), physological (heart rate/blood pressure, EKG) and subjective measures (Beck Depression Inventory, Craving Questionnaire). We hypothesized that cocaine administration would lead to increased blood levels of norpinephrine, epinephrine and cortisol in cocaine dependent subjects.