A 70-year-old woman was admitted to the hospital with confusion and a plasma glucose level of 1.11 mmol/L (20 mg/dL). Confusion cleared after glucose injection. She was well nourished (height, 152 cm; body weight, 49 kg), had never been hospitalized, had no medical history, and was receiving no medications. Owing to the impairment of her growth hormone (GH) responses to the insulin tolerance, arginine, and glucagon tests (peak GH was below 222 pmol/L [5 µg/L]), she was diagnosed with GH deficiency. Other pituitary hormones were within normal limits, and brain magnetic resonance imaging revealed no pathologic changes in the pituitary gland. She was treated with frequent glucose feedings at night to prevent severe fasting hypoglycemia.