This Association of Exotic Mammal Veterinarians client education handout provides a comprehensive overview of insulinoma, an abnormal growth of the pancreas that secretes excess amounts of insulin. Unfortunately, insulinoma is an extremely common disease of middle-aged to older ferrets in some nations. Client education is crucial for owners of affected ferrets. Teach owners to recognize signs of hypoglycemia and to prevent hypoglycemic episodes from occurring. Owners must also recognize situations that can precipitate a hypoglycemic crisis and take measures to minimize stressors whenever possible. Additional preventive measures are also explored.