Administration of "highly purified pituitary growth hormone" to a diabetic patient under chemically controlled conditions resulted in increased hyperglycemia and glycosuria, in minimal increase in blood ketones, and in urinary N; in actual K retention; and in elevation of the R.Q. above 1, rather than below 0.7. (The latter is noted consistently in diabetics receiving ACTH.) The data support the concept that the increased hyperglycemia and glycosuria are probably attributable to diminished carbohydrate utilization, rather than to increased neoglucogenesis. The diminished utilization in turn may be referable to diminished endogenous insulin production as the result of the exhaustion of the beta cells of the islets.