Information on symptoms of Cushing's Disease to help with elevated cortisol levels in cats and dogs.

What is Cushing’s Disease?

Cushing’s disease, also known as hyperadrenocorticism is a condition that develops as a result of the overproduction or excessive amounts of cortisol in the body. This is a slow, gradual disease that commonly affects dogs more than cats. Middle-aged to older dogs, particularly breeds such as German shepherds, poodles, golden retrievers, terriers and dachshunds are more prone to this condition.

When cats develop Cushing’s disease, it is usually in conjunction with diabetes mellitus. Many pet-owners mistake Cushing’s disease as a natural part of aging but, fortunately this disease is treatable. If you notice any abnormal physical and behavioural changes in your pet, consult your vet immediately. Although this disease cannot be cured, it is manageable and many pets continue have quality of life.

There are three forms of Cushing’s disease and these include adrenal-based hyperadrenocorticism, pituitary dependent hyperadrenocorticism and iatrogenic hyperadrenocorticism:

Adrenal-based hyperadrenocorticism
This condition develops as a result of an adrenal tumor that causes an overproduction of glucocorticoids. It is estimated that adrenal tumors are the cause for at least 15 to 20% of Cushing’s disease cases. These tumors are enlarged in one adrenal gland while are very small in the other gland.

Pituitary-dependent hyperadrenocorticism
Pituitary-dependent hyperadrenocorticism occurs as a result of the overproduction of the ACTH hormone by the pituitary gland in the brain due to pituitary tumors. Both adrenal glands are enlarged affecting approximately 80% of the cases of Cushing’s disease.

Iatrogenic hyperadrenocorticism
Iatrogenic hyperadrenocorticism develops when a pet is given too many glucocorticoids for health problems such as allergies or skin disorders. The adrenal glands tend to be very small because of the overproduction of glucocorticosteroids.

The common symptoms and signs of Cushing’s disease include:

• Increased drinking
• Increased urination
• Excessive eating
• Enlarged abdomen
• Hair loss or thin skin
• Lethargy
• Rapid/ Fast Breathing
• Recurring urinary tract infections

What Causes Cushing’s Disease?

In a healthy pet, the pituitary gland which is located at the base of the brain produces adrenocorticotrophic hormone (ACTH) stimulates the adrenal glands to secrete glutocorticoid or cortisol hormones into the bloodstream.

Glucocorticoid is necessary for the body to function at optimal level and affects the metabolism, nervous system, immune system, cardiovascular system and kidneys. When the pituitary gland or adrenal gland malfunctions and excess glucocorticoid is secreted, your pet develops Cushing’s disease.

Diagnosing Cushing’s Disease

The diagnosis of Cushing’s disease is based on the symptoms, medical history and a thorough physical examination. If Cushing’s disease is suspected, certain tests such as a complete blood count, blood chemistry panel and urinalysis will be performed.

Further screening tests such as a urine cortisol, creatinine ratio, low dose dexamethasone suppression test, ultrasound, high dose dexamethasone suppression test and the ACTH stimulation test may be performed to obtain a definitive diagnosis of Cushing’s disease.

Help for Cushing’s Disease

Depending on the severity of your pet’s condition, your vet may recommend various treatment options. Oral medications such as Mitotane (Lysodren), Ketoconazole, L-deprenyl (Amery) or Trilostane are typically prescribed for canine Cushing’s disease. Mitotane is the most widely used medication, similar to chemotherapy. This type of therapy is life-long, and while undergoing therapy, your pet has to be monitored carefully to determine whether the treatment is successful.

These medications have some serious side effects and can also become very costly – consult with your vet about a treatment that best suits your pet needs. With treatment, improvement may be noticed within 4 to 6 months.

If your pet develops Cushing’s disease because of the overuse of corticosteroids to treat allergies or skin disorders, your pet may have to be weaned off the medication first. In severe cases where a tumor may develop in the adrenal glands, surgery may be required.

PetAlive offers two great options for managing symptoms of Cushing's disease. Cushex Drops-S for Cushing's related support and Cushex Drops-M for Cushing's symptoms relief. 

More Information on Cushing’s Disease

Although Cushing’s disease cannot be prevented, there are certain things that you can do to strengthen your pet’s immune system and alleviate some of the symptoms: