The clinical and EEG findings were reviewed for 270 juvenile children from the Montreal Children's Hospital Diabetic Clinic in an attempt to correlate the EEG findings at the onset of diabetes mellitus with the future risk of having a convulsion with a hypoglycemic reaction. Compared to a non-diabetic control population, the number of epileptiform EEG abnormalities was significantly increased in the initial EEG of diabetic patients who later had a hypoglycemic convulsion. The initial epileptiform EEG did not help to differentiate those diabetics with recurrent hypoglycemic induced convulsions from diabetics who would have only a single convulsion.