Adrenal and urinary levels of adrenaline and noradrenaline were determined in rats subjected to severe ethanol intoxication for periods of up to 96 hours, in rats undergoing withdrawal and in a post-withdrawal period, and in controls. Adrenaline and noradrenaline content of adrenal glands fell markedly to less than eight and twenty percent, respectively, after four days of intoxication. Noradrenaline content, but not adrenaline content, had recovered after a subsequent four day period of recovery. The depletion in adrenal catecholamine levels was coincident with increases in urinary adrenaline and noradrenaline levels over the first 48 hours of intoxication. Urinary catecholamine levels remained higher than control values for the next 48 hours of intoxication. Adrenal glands were larger after 12 hours of intoxication, although there was no increase in dry weight. At later times adrenal enlargement was associated with increased dry weight and protein content. This increase in mass was found to be of cortical origin. These results demonstrate that severe ethanol intoxication promotes an intense stimulation of the rat adrenal gland with enhanced synthesis and release of catecholamines, and cortical hypertrophy.