Effect of lactate administration on brain lactate levels during hypoglycemia in patients with type 1 diabetes.

Administration of lactate during hypoglycemia suppresses symptoms and counterregulatory responses, as seen in patients with type 1 diabetes and impaired awareness of hypoglycemia (IAH), presumably because lactate can substitute for glucose as a brain fuel. Here, we examined whether lactate administration, in a dose sufficient to impair awareness of hypoglycemia, affects brain lactate levels in patients with normal awareness of hypoglycemia (NAH). Patients with NAH ( = 6) underwent two euglycemic-hypoglycemic clamps (2.