In recent years, it has become apparent that lesions of the suprarenal glands occur more often in human disease than had formerly been suspected. The evident effect of such lesions is the production of profound general disturbances, which are seen in a chronic phase if the morbid process in the suprarenal tissue is slowly progressive, as, for example, in the ordinary case of Addison's disease, and in an acute phase if the lesion is of sudden onset, as in suprarenal haemorrhage, or if chronically diseased suprarenal tissue is subjected to sudden excessive demands, as in the critical stage of Addison's disease. In both phases, there is evidence to show that the best measures to employ in combating these disturbances, whether for prophylaxis or for therapy, consist of the administration to the patient of an extract of suprarenal cortex or, alternatively, of sodium chloride.