A well-documented case of a 35-year-old male Type 1 diabetic patient who was admitted as an emergency after having injected 1500 international units (IU) of insulin (750 IU regular insulin,750 IU NPH-insulin) subcutaneously as a suicidal attempt is reported. Computing disappearance rates of glucose from its infused amounts necessary to maintain euglycaemia during 65 h after the insulin injection in analogy to experimental hyperinsulinaemic euglycaemic clamp examinations, a glucose consumption of 55.6 mumol kg-1 min-1 was found at peak serum insulin concentrations of about 14,400 pmol l-1. The insulin-induced glucose dynamics resemble closely those seen in healthy persons and Type 1 diabetic subjects during a 10 mU kg-1 min-1 euglycaemic clamp. This information may be useful in the handling of similar cases of insulin intoxication.