The International Hypoglycaemia Study Group recommends that the frequency of detection of a glucose concentration< 3.0 mmol/l (< 54 mg/dl), which it considers to be clinically significant biochemical hypoglycaemia, be included in reports of clinical trials of glucoselowering drugs evaluated for the treatment of diabetes mellitus.

The glycaemic thresholds for symptoms of hypoglycaemia and for glucose counterregulatory (including sympathoadrenal) responses to hypoglycaemia, as plasma glucose concentrations fall, are not fixed in patients with insulin-, sulfonylurea-or meglitinide-(glinide)-treated diabetes. They are at higher glucose concentrations in those with poor glycaemic control and at lower glucose concentrations in those with tight glycaemic control [1–5]. The shifts in glycaemic threshold to lower glucose concentrations are largely the result of more frequent episodes of iatrogenic hypoglycaemia during intensive glycaemic therapy. Glycaemic thresholds for responses to hypoglycaemia vary, not only among individuals with diabetes but also in the same