Hypoglycaemia definitions have varied across time, place, and setting. In order to harmonize terminology in clinical trials and encourage an appropriate response to hypoglycaemia in clinical practice, the IHSG has developed the following definitions:

These definitions partly align with the American Diabetes Association/Endocrine Society (ADA/ENDO) hypoglycaemia classification system.1 An important difference is that ADA/ENDO classifies blood glucose < 3.9 mmol/L without symptoms as “asymptomatic hypoglycaemia.” The IHSG takes the position that “alert value” more accurately reflects this presentation and avoids over-identifying hypoglycaemia.

The above IHSG definitions do not apply to young children, who are generally not able or expected to self-treat. The International Society for Paediatric and Adolescent Diabetes (ISPAD) characterizes severe paediatric hypoglycaemia as follows: “The child is having altered mental status and cannot assist in their care, is semiconscious or unconscious, or in coma.”2


  1. Edelman SV, Blose JS. the impact of nocturnal hypoglycemia on clinical and cost-related issues in patients with type 1 and type 2 diabetes. Diabetes Educ 2014;40:269.
  2. Seaquist ER et al. Hypoglycemia and diabetes: a report of a workgroup of the American Diabetes Association and The Endocrine Society. Diabetes Care 2013;36:1384.