This study's purpose was to test whether beta-adrenergic blockade reduces awareness of hypoglycemia. Six non-diabetic human adults received six experimental sessions each, one with each combination of intravenous propranolol (0.0, 0.05, and 0.15 mg/kg) followed by intravenous regular insulin (2 and 4 units). Physiological, biochemical, and symptom variables, and choice (was an active or an inactive substance administered?) were measured at 15, 30, and 45 min after insulin. Insulin dose and time after insulin administration significantly influenced choice, but propranolol did not significantly influence choice. Adrenergic symptoms were not prominent. These results may or may not apply to individuals with disorders of adrenergic function such as diabetic autonomic neuropathy.