Toxic dose

Any dose of insulin in a patient without diabetes, or any dose more than the usual therapeutic dose in a patient with diabetes, can cause significant hypoglycaemia. The duration of hypoglycaemia depends on the dose and the type of insulin. Patients with type 2 diabetes often have insulin resistance, so they have a lower risk of hypoglycaemia following insulin poisoning.

Insulin poisoning usually occurs parenterally; ingestion of insulin is uncommon and unlikely to cause hypoglycaemia because insulin has poor oral bioavailability (less than 1%).