These studies describe the effects of ethanol on the adrenal medulla of rats. Ethanol intake for 3 weeks in the form of a liquid diet increased catecholamine content by 14 percent; the increase was mainly due to a rise in epinephrine content. Concomitantly, there was a 16-percent increase in PNMT activity. On withdrawal of ethanol from the diet, catecholamine synthesis from 3-H-tyrosine was greatly stimulated; this effect and the behavioral symptoms of withdrawal could be partially prevented by giving an injection of ethanol. Gradual ethanol withdrawal from the diet did not lead to stimulation of the adrenal medulla.