Symptoms and Signs of Insulin Reaction

Doctor's Notes on Insulin Reaction

An insulin reaction occurs when a person with diabetes becomes confused or unconscious due to low blood sugar (hypoglycemia) caused by insulin or oral diabetic medications. In people with diabetes, the pancreas is unable to produce enough insulin to meet the body's demand and treatment may include oral hypoglycemics, insulin, or both. A common cause of an insulin reaction (or hypoglycemia) is a missed meal. Other causes for insulin reaction include exercise and medication error.

Mild symptoms of insulin reaction include dizziness, irritability, hunger, shakiness, sweating, and rapid heartbeat. Moderate symptoms of insulin reaction include confusion, headache, and poor coordination. Severe symptoms of insulin reaction include unconsciousness, seizures, coma, stroke-like symptoms, and hypothermia (low body temperature) if the hypoglycemia persists for a prolonged period of time.

Medical Author: John P. Cunha, DO, FACOEP
Medically Reviewed on 3/21/2019


Kasper, D.L., et al., eds. Harrison's Principles of Internal Medicine, 19th Ed. United States: McGraw-Hill Education, 2015.