Do endocrinologists perform the test that confirms hypoglycemia?

Yes: In a non diabetic person, suspected hypoglycemia needs to be confirmed with a fasting test. Because of the risks, the test has to done in a hospital, where the patient can be monitored. When and if the blood sugar drops, the Insulin is measured, to understand whether the condition is cause by unregulated Insulin secretion.

Hypoglycemia.: We diagnose hypoglycemia if a patient has (1) appropriate symptoms of hypoglycemia, (2) documented low blood sugar, either by fingerstick or lab test, and (3) appropriate positive response (resolution of symptoms) with administration of glucose/sugar. Can be confirmed by an oral glucose tolerance test, performed in a lab.

72 hour fast: If they are looking for an Insulin producing tumor ( insulinoma), you may be asked to fast for a maximum of 72 hours. If and when you develop hypoglycemia during that time, labs will be drawn to determine the cause.