Intentional insulin overdose associated with minimal hypoglycemic symptoms in a non-diabetic patient

Non-accidental suicidal insulin overdose is a rare presentation among non-diabetic patients. It seems to be more common among working medical professionals.

To present the case of a young patient, who despite injecting a large dose of rapid-acting insulin presented with only mild symptoms, and to familiarize the medical professionals involved in managing this condition with the recognition, pathophysiology and appropriate therapeutic interventions.

We report the case of a previously healthy non-diabetic young medical professional who presented with a rapid-acting insulin overdose. On initial assessment the patient was alert and oriented, and glucose measurement was 1.4 mmol/L. The oral glucose gel and intramuscular glucagon failed to raise the glucose. Hypokalaemia, hypomagnesaemia, hypophosphataemia, lactic acidosis and ECG changes completed the presentation.

The treatment consisted of dextrose infusion and appropriate electrolytes replacement. An uneventful recovery was made, so 36 hours later the patient was discharged with psychiatric follow-up.

Insulin overdose should be considered as a differential diagnosis in hypoglycaemic patients when blood glucose fails to correct as expected. Improper management carries a significant risk of hypoglycaemic encephalopathy, which can cause lifelong cerebral changes.