- Severe Susceptibility to Hypoglycemia (serum glucose <60 mg/dL) after short periods of fasting (less than 4-12 hours, depending on age), with at least 2 events in the last year that require ongoing prophylactic management, OR recurrent symptomatic hypoglycemia (blood glucose levels or clinical symptoms of hypoglycemia) at home requiring intervention ≥ 2 times per week,