Cushing's disease is the result of the overproduction of cortison, a natural steriod hormone, by the adrenal glands. In the majority of cases, the disease is caused by a lesion in the pituitary gland at the base of the brain that overstimulates the adrenals, while in about 20 percent of cases one of the adrenal glands itself will have a tumor that excretes cortisol independent of what's happening in the body. About half of those tumors are malignant and spread, and about half of them are benign and generally remain small.
Typical signs of Cushing's Disease include increased thirst and urination, panting, hair loss (usually on the trunk) and weakness. It is rare for a dog under the age of five years to have Cushing's Disease.
Note: This section of Canada's Guide to Dogs is intended as a source of information only. It is not intended as a substitute for professional care. Always consult with your Veterinarian about health related matters.