An insulinoma is a malignant tumor of the pancreas that secretes excessive amounts of insulin leading to hypoglycemia (low blood sugar concentration). Insulinomas usually occur in middle-aged to older dogs, usually eight to twelve years of age. They are very rare in cats and there is no apparent gender predilection.
Insulinomas can occur in any breed of dog with mixed breed dogs most commonly affected. Among purebred dogs, Irish setters, German shepherds
, boxers, golden retrievers, poodles
, and Labrador retrievers have a higher incidence. Medium to large-sized breeds of dogs are most commonly affected.
The excessive secretion of insulin by these tumors causes hypoglycemia and clinical symptoms of hypoglycemia. What to Watch For Seizures
Fainting (also called syncope)
Hind limb weakness
Polyphagia or increased appetite