• Severe acidosis occurring in an obese woman, with a blood sugar level above 700 mg. per 100 cc., abated after the patient had received a total of 11,425 units of insulin during a 21.5-hour period. After recovery from this episode she gradually became able to get along entirely without insulin. In another instance a diabetic woman who normally subsisted on 60 to 100 units required 21,750 units within a 16-hour period. Various factors that increase resistance to insulin are known, but a common factor in these two cases was infection. Breast abscess and endometritis were involved in the first case. Ulcerative colitis, local peritonitis, and foci of lobular pneumonia were found at autopsy in the second.