Insulin glargine treatment of a ferret with diabetes mellitus.

Case Description: A 7.5-year-old spayed female ferret was evaluated because of weight loss despite a good appetite. Pancreatic insulinoma had been diagnosed at another animal hospital on the basis of detection of low blood glucose concentration on 1 occasion; however, concurrent determination of blood insulin concentration was not performed. The ferret had been treated SC with methylprednisolone acetate (unknown dosage) every 30 days for 2 years. No follow-up data regarding blood glucose concentration were available.
Clinical Findings: On physical examination, the ferret was thin (weight, 0.619 kg [1.36 lb]) and bruised easily. Serum biochemical analysis revealed hyperglycemia (blood glucose concentration, 855 mg/dL; reference range, 63 to 134 mg/dL).
Treatment and Outcome: Glucocorticoid injections were discontinued, and the ferret was administered prednisolone (1.13 mg/kg [0.51 mg/lb], q 12 h for 14 days, then 0.56 mg/kg [0.25 mg/lb], q 12 h for 7 days) orally. After prednisolone administration was discontinued, hyperglycemia and weight loss persisted. The ferret was administered insulin glargine (0.5 U) SC; blood glucose concentration was monitored every 2 hours for 24 hours, at which time the value had decreased to nearly within reference range. The owner continued insulin glargine administration at that dose every 12 hours; after 77 days of treatment, the ferret's weight was 0.731 kg (1.61 lb), which was considered normal, and blood glucose concentration was within reference range.
Clinical Relevance: Regular SC administration of insulin glargine was successful in the treatment of diabetes mellitus in the ferret of this report and may be effective for other diabetic ferrets.