SummaryHuman growth hormone was administered in doses of 5 mg daily to a female pituitary dwarf aged 14 years.Marked retention of nitrogen, potassium and phosphorus was demonstrated.There was also some retention of sodium and water. Urinary calcium excretion increased. The level of plasma N.E.F.A. rised markedly.Insulin sensitivity and the rate of glucose uptake by the tissues were reduced but the fasting blood sugar level was unchanged.Studies of long term administration of this growth hormone with particular reference to its effect on height are in progress.