A two-year-old girl was admitted on account of impaired consciousness, hypoglycaemia and hypotension. In differential diagnostic considerations in view of the family-history a hereditary metabolic disorder was suspected but was not confirmed. On examination of hormones higher serum insulin and C-peptide levels esere found. Toxicological examination of the gastric contents and urine surprisingly revealed most probable ingestion of glibenclamide, an oral antidiabetic from the group of sulphonyl urea derivatives. The low blond sugar levil and the transient hyperinsulinism is according to the authors due to accidental intoxication with glibenclamide. The lati onset of serious hypoglycaemia is explained by the simultaneously ingested netrendipine, a calcium channel blocker which may partly antagonize the hypoglycaemic effect of glibenclamide. The authors draw attention to the fact that obscure hypoglycaemia in childhood may be caused by intoxication with oral antidiabetics and recommend at the sami time its treatment. The problem is that toxicological screening dnes not detect the presence of drugs from the sulphonyl urea group.

        Key words: sulphonyl urea derivatives, glibenclamide, netrendipine, hypoglycaemia, hyperinsulinism