Cushing's disease, or syndrome, is technically known as hyperadrenocorticism (HCV). It is a result of too much of the adrenal hormone hydrocortisone circulating in the body.

Too Much of a Good Thing
Cortisone is necessary for a wide variety of functions. It helps the body respond to stress, is important in fat metabolism, blood sugar regulation and the immune response. It also is important to most organ systems, muscles and nerves.

Signs and Symptoms
There is a huge range of symptoms associated with Cushing's, due to the wide-ranging impact of cortisone, or corticosteroids.

Symptoms include muscle weakness and wasting; excessive urination, increased appetite, heat intolerance and thinning of hair and skin. You may also notice panting, calcified lumps in the skin or sagging of the abdomen. Other clinical signs include weakening of the heart muscle, high blood pressure and nervous system disorders.

The condition is usually seen in overweight dogs over the age of six, it is rarely seen in cats. It is often associated with diabetes and pancreatitis.

Diagnosis and Testing
Cushing's disease can be difficult to diagnose. There are a variety of tests available and none are 100% accurate due to fluctuating levels of hormones throughout the day. It is possible for a dog to display clinical symptoms yet never show high enough cortisol levels in testing.

The primary cause of this disease is a tumor on the pituitary gland. In about fifteen percent of the cases it is caused by adrenal gland tumors.
Once a diagnosis has been made, further testing can determine the nature of the tumor.

Cushing's can also be brought on by long-term use or high doses of steroid drugs. It is usually quickly reversible by discontinuing the drug use.

Managing and Treating the Disease
Treatment options include surgery or medication, depending on where the tumor is located.

Dietary therapy is also a part of the disease management. Reduce or eliminate the grains in the dog's diet.

In addition to the medication, some measures can be taken to manage the symptoms and keep the dog comfortable. Keep the dog cool in hot weather. You may need to purchase a cooling mat. For the outdoor dog you could provide a shallow wading pool, or keep a wet T-shirt on the dog in the summer.

The use of ramps and steps may help compensate for muscle weakness. Cover slick floor surfaces with carpet runners, especially in the area where the dog eats.

Related Disease
A less common adrenal disorder that is also seen in dogs is Addison's disease, which is the underproduction of both adrenal hormones. In addition to the glucocorticoids (cortisone), the adrenal glands also produce a class of substances known as mineralocorticoids. These hormones control the sodium and potassium levels in the body.

Causes of Addison's
Addison's is usually caused by the destruction of the glands and the cells that produce the hormones. The destruction may be due to a malfunction of the dog's immune system, occasionally it is caused by cancer or an infection.

Symptoms and Testing
Symptoms often seem to come on quickly, and all develop at the same time. These include loss of appetite, lethargy, vomiting, diarrhea and weight loss.
These symptoms are common to any number of diseases, and could involve practically any of the organ systems, which makes Addison's difficult to recognize. The tests that are usually done that will look at all the organ systems at the same time.

Treatment not Complicated
Once it is diagnosed, it is easy to treat. Long-term hormone replacement therapy will be necessary, but the animal so treated can then go on to live a normal healthy life.

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