About Cushing's Disease in Dogs

Cushing's disease in dogs can lead to serious symptoms and health complications that can threaten your pup's longevity. Our Huntersville vets explain what causes Cushing's disease in dogs, as well as complications and treatments.

What is Cushing's Disease in dogs?

Cushing's disease (hyperadrenocorticism) is a serious health condition in dogs that occurs when the adrenal glands overproduce cortisol (cortisone) in the animal's body. Excess cortisol can put a dog at risk of several serious conditions and illnesses, from kidney damage to diabetes, and can be life-threatening.

In dog's Cushing’s disease is commonly caused by a benign or malignant tumor in the pituitary gland, a pea-sized gland located at the base of the brain. In some more rare cases the tumor could be located on the adrenal glands, located on top of the kidneys.

Iatrogenic Cushing's syndrome is caused by excessive cortisol production stemming from the prolonged use of steroids. 

What are the symptoms of Cushing’s disease in dogs?

Dogs with Cushing’s disease will experience at least one of the following symptoms but sometimes more:

• Increased appetite
• Excessive thirst or drinking
• Thinning of the skin 
• Hair loss
• Frequent urination 
• Muscle weakness
• Enlarged abdomen, potbellied appearance
• Panting
• Lethargy

If you spot any of these symptoms in your dog contact your vet immediately. Dogs with Cushing’s disease face an increased risk of developing kidney damage, blood clots, high blood pressure and diabetes

How is Cushing’s disease diagnosed?

Your veterinarian will do a physical exam and run a few tests to determine what may be causing your pet's symptoms as well as to rule out other health problems. The tests may include, but are not limited to, urinalysis, urine culture, complete blood panel, and/or full chemistry panel.

Your veterinarian may also run adrenal function tests, adrenal low dose testing, and high dose dexamethasone suppression tests. However, adrenal function tests can result in false positives when another disease with similar clinical signs is present.

An ultrasound may help to rule out other conditions that could be causing your dog’s symptoms. Other diseases that may cause similar symptoms include tumors in the spleen or liver, bladder stones, gallbladder disease, gastrointestinal disease, chronic inflammatory liver disease.

Magnetic resonance imaging (MRI) is typically the most effective diagnostic testing tool for Cushing’s disease since it allows your vet to assess your dog’s adrenal glands. However, MRI testing can be costly. 

What are the treatments for Cushing’s disease in dogs?

Treatment for Cushing's disease in dogs usually includes medications that help decrease the amount of cortisone that the adrenal glands produce. The only way to cure Cushing's disease is to remove the tumor, however, due to the complexity and risks of surgery, most cases are treated with medication.

Treatments will vary based on the type of Cushing’s your dog has.

Pituitary tumor. Treatment of pituitary dependent Cushing’s disease is the most complicated. Two drugs, trilostane and mitotane are commonly used. 

Adrenal tumor. Treatment of an adrenal dependent Cushing’s disease will usually require major abdominal surgery. If the entire tumor is able to be removed and the tumor is not malignant, there is a good chance that your dog will regain normal health. 

Iatrogenic Cushing’s disease. Treatment requires gradual discontinuation of the steroid, usually resulting in a recurrence of the disease that was being treated by the steroid. After starting the medication treatments your dog will need to see the vet regularly for ACTH stimulation tests, until the excessive production of cortisone is controlled. Over their lifetime of your pet, routine monitoring of blood tests and medication adjustments need to be made. 

Do dogs with Cushing’s disease suffer?

Health issues caused by Cushing’s disease can be minimized with diligent observation and long-term management. 

Many dogs with Cushing's can be successfully treated with few medication side effects. However, the wrong dose can cause mild or severe side effects. Therefore, your pet must be carefully monitored and follow-up blood tests are essential.

Dogs who do not receive adequate monitoring and follow-up often experience relapses and severe illness or death, as a result of complications.

Note: The advice provided in this post is intended for informational purposes and does not constitute medical advice regarding pets. For an accurate diagnosis of your pet's condition, please make an appointment with your vet.