Cushings disease in dogs is a glandular disorder caused by excessive corticosteroids. The process of the production of these corticosteroids is such that:
The pituitary gland produces a hormone called ACTH. The ACTH stimulates the adrenalin glands. The adrenalin gland produces corticosteroids.
A more than required amount of corticosteroid can cause Cushings disease, so it is also called hyperadrenocorticism (hyper-adreno-corticism).
The overproduction of corticosteroids which causes Cushings disease in dogs can occur due to two types of conditions. In 85% of the cases, the excessive production of ACTH is caused by a tumor in the pituitary gland that produces high levels of ACTH.
This causes the adrenalin glands to make more than required levels of corticosteroids. Hyperadrenocorticism in a dog can also be caused by a corticosteroid-producing tumor in one or both of the adrenalin glands.
Cushings disease in dogs can also be caused by large doses of synthetic corticosteroids. These steroids may be administered for treating another ailment but in turn produce a side effect that results in Cushing's disease.
Cushings disease generally occurs in dogs that are five years or older. It is more common in female dogs than in male dogs. Some breeds like Terriers, Poodles, and Dachshunds are more prone to Cushing's disease for some inexplicable reason.
Cushing's disease affects the overall health of the dog, since corticosteroids play an important role in a large number of body functions.