As the disease develops over many months, symptoms become increasing severe and ultimately fatal. Initially episodes of weakness or disorientation arise, then quickly pass after a matter of several seconds or minutes. Ferrets may stand still, staring blankly during a hypoglycemic episode, or may temporarily drag the rear legs while moving about. As the disease progresses and the tumors grow, the ferret may salivate and make chewing motions. Rubbing or pawing at the face is also frequently noted during a hypoglycemic attack.
Episodes become more frequent and more severe, ultimately leading to collapse, seizures or coma.
Diagnosis of insulinoma in the ferret can usually be made, or strongly suggested, on the basis of fasting blood glucose levels. Assays of blood insulin taken at the same time as the blood glucose test can be helpful in diagnosing insulinomas in ferrets whose glucose levels alone are equivocal. Treatment recommendations for insulinomas may vary, but I believe insulinomas initially are best treated by surgical exploration and removal if possible. This allows a confirmation of the diagnosis, and it provides the veterinarian with an opportunity to remove any obvious pancreatic masses. Insulinomas may occur singly or as groups of small nodules.