Hyperadrenocorticism (Cushing's Syndrome) in Cats

Optimal treatment for your pet requires a combination of home and professional care. Follow-up can be critical, especially if your pet does not rapidly improve. Administer all prescribed medications as directed. Alert your veterinarian if you are experiencing problems treating your pet.

The surgical treatment of removing both adrenal glands in the cat with Cushing's disease creates another condition, Addison's disease (hypoadrenocorticism), which requires life long medications and very close monitoring.

Glucocorticoid therapy with prednisone will be required since your cat is no longer producing cortisol. It is usually possible to decrease the dose of prednisone down eventually to very small maintenance dosages. When decreasing the dose it is important to monitor for increased lethargy, anorexia or weakness.

Notifying your veterinarian and increasing the prednisone dose usually improves the symptoms if they are being caused by a cortisol deficiency.

Additionally, life long replacement therapy with the mineralocorticoid, fludrocortisone acetate (Florinef) is required. This drug maintains the normal electrolyte balance of sodium, potassium and chloride. Frequent blood tests are needed, especially for the first few weeks postoperatively. Adjustments in medication are made on the basis of the electrolyte results. Florinef is increased if the blood potassium is elevated. If needed, salt may be added to the diet to elevate blood sodium and chloride levels.

Injectable mineralocorticoids (desoxycorticosterone pivalate or DOCP) can be given as a monthly injection instead of the daily oral medications.

Since most cats are diabetics, the blood sugar level will need to be closely followed. Once the Cushing's disease is controlled, it is common for insulin requirements to decrease dramatically. Watch for changes in drinking, urination and attitude. You will need to work closely with your veterinarian to decrease insulin dosages and to avoid a hypoglycemic (low blood sugar) event. Watch for weakness, disorientation or seizures, as they may indicate a low blood sugar.

After the first several weeks postoperatively, the long-term prognosis is good.