What are the main causes of hypoglycemia in adult non-`diabetic patients?

Drugs (insulin or insulin secretagogue, alcohol..) Critical illnesses (hepatic, renal or cardiac failure, sepsis (in ICU seen), inanition (hunger). Hormone deficiency (cortisol, glucagon and epinephrine- for insulin deficient DM pt) Nonislet cell tumor (IGF-II producing tumor) Endogenous hyperinsulinism Accidental, surreptitious, or malicious (admin of insulin)