Suppression of plasma cortisol in depressed patients by acute intravenous methadone infusion

A cardinal biochemical finding in major depressive illness is activation of the hypothalamic-pituitary-adrenal (HPA) axis. This activation is manifested both by an overall increase in the daily 24-hour production rate of corticosteroids as well as disruption of the circadian pattern of corticosteroid secretion. To explore the possible interface between endorphinergic and HPA function, the authors present here a report that, represents the first study examining the effects of exogenous opiate administration on HPA function in patients with a major depressive disorder. It is proposed that the development of a methadone suppression test could be utilized to explore the possible relationship between endogenous opiate function and HPA activation in depressed patients.