Cushing's Disease in Dogs: Symptoms, Diagnosis, Medications (2024)

Is your middle-aged or senior dog drinking and urinating more than usual? Does your dog have a pot-bellied appearance? These are just a few signs of Cushing’s disease in dogs (also known as hyperadrenocorticism). Integrative veterinarian Dr. Julie Buzby shares symptoms, diagnosis, medications, and other treatment options for Cushing’s disease in dogs.

“Have you ever heard of Cushing’s disease in dogs?” I asked my new veterinary client, the loving parent of a 15-year-old Labrador Retriever, Jake. As I was rubbing her senior dog’s pot belly, I sensed my client’s fear and worry. I had just met Jake forty minutes prior and diagnosed two other conditions—hip dysplasia and laryngeal paralysis in dogs.

Now, I suspected her canine companion had Cushing’s disease, which is also known as hyperadrenocorticism. As a veterinarian, it’s a medical condition that I’ve diagnosed often since it’s fairly common in senior dogs—who make up the majority of the patients in my practice.

If your dog has been diagnosed with Cushing’s, you may have questions and concerns much like my client. Along with your veterinarian’s recommendations, please use this ultimate guide to Cushing’s disease to help you help your dog have the best quality of life possible.

What is Cushing’s disease in dogs?

Cushing’s disease (or Cushing’s syndrome) occurs when the body produces too much cortisol, a stress hormone. Cortisol is the body’s natural steroid and is absolutely essential for day-to-day life. The body regulates cortisol levels very carefully. When the amount of cortisol gets out of whack, bad things can happen!

What causes Cushing’s disease in dogs?

As dogs age, they can develop small tumors that cause excess release of cortisol. These tumors are usually in the pituitary gland, a small structure in the brain that controls hormone secretion.

Do not fear though! While the phrase “brain tumor” is frightening when used in the same sentence with our beloved dogs, these tumors are usually pea-sized and do not spread. Instead, they disturb the normal secretion of hormones in the body. The end result is excessive cortisol. This is the case in about 80% of dogs with Cushing’s disease.

In the other 20% of dogs, a tumor grows on the adrenal gland. (Adrenal glands are small, bean-shaped organs found just above the kidneys. They make cortisol.) However, the end result is essentially the same. These tumors also lead to elevated levels of cortisol in the body.

Also, I think it is important to mention iatrogenic Cushing’s disease. The term “iatrogenic” indicates that a medical treatment or procedure accidentally caused the condition. The administration of prednisone for dogs or other corticosteroids may cause iatrogenic Cushing’s disease. These drugs mimic the action of cortisol in the body, so they can cause identical symptoms to adrenal or pituitary tumors.

Playing the odds, I suspected my Lab patient had a small brain tumor called a pituitary microadenoma.

Jake’s Cushing’s disease clues

But let’s back up for a second. Why did I suspect Jake had Cushing’s disease? In my conversation with the my client, she had mentioned noticing Jake’s thirst, urination, and panting were increased. These are three cardinal symptoms of Cushing’s disease in dogs.

Also, while I was speaking with my client, I sat rubbing the thin skin of Jake’s pot belly. (Yes, thin skin and a pot belly are two more cardinal symptoms.) In additional to these, what are other clinical signs and symptoms of Cushing’s disease? The list is long.

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

If you have ever taken a steroid (for example, prednisone) for a medical condition, you may have felt restless or had an increased appetite. The symptoms of Cushing’s disease in dogs are similar to some of the side effects human patients experience when taking steroids.

Symptoms of Cushing’s disease in dogs may include:

• Restlessness, which may include senior dog anxiety at night
• Panting
• Possible behavior changes
• Increased drinking and urinating
• Increased appetite
• Weight gain
• A pot-bellied appearance
• Thinning skin
• Weakness
• Muscle wasting or loss of muscle mass (It’s worth noting that due to the loss of muscle mass, a dog suffering from arthritis may suddenly worsen.)
• Hair loss
• Skin changes—much like that of a teenager!
• Skin infections (called pyoderma)
• Urinary tract infections

Also, it’s important to mention that dogs with Cushing’s disease are more prone to infections. This is why skin infections and urinary tract infections in dogs are on the list. Both of these can be recurrent.

How is Cushing’s disease diagnosed?

As an integrative veterinarian, I believe that knowledge is power. In order to intelligently discuss a dog’s prognosis (expected outcome) and treatment plan, I begin by confirming the diagnosis.

I recommend that my client starts with a simple test called a urine cortisol creatinine ratio(UCCR). This test is collected at home and rules OUT the diagnosis, rather than ruling it IN. Let me explain…

Testing to rule OUT Cushing’s disease

First, the UCCR test measures cortisol in a urine sample. Cortisol is the hormone “over produced” in Cushing’s syndrome, but animals and people naturally produce it as part of a healthy response to stress.

For best results, the client should collect the dog’s urine sample at home. This way, the dog doesn’t get anxious from a visit to the veterinary clinic, secrete a bunch of cortisol, and skew the results.

However, an elevated UCCR simply indicates your dog COULD have Cushing’s disease. Thus, we would need to run more tests.

Testing to confirm Cushing’s disease

Tests to rule IN Cushing’s (aka confirm the diagnosis) are blood tests. There are three options: the ACTH stimulation test, a low dose dexamethasone suppression test, or a high dose dexamethasone suppression test.

Each of these tests has some pros and cons. Your vet will select the one that he or she thinks is right for your dog. In some situations, your vet may recommend more than one of these tests, especially if trying to differentiate between the three types of Cushing’s disease.

Occasionally, the results are still not conclusive. In order to nail the diagnosis, an abdominal ultrasound, X-rays of the chest or abdomen, further bloodwork, or other tests may be recommended.

In addition to tests to rule out or confirm Cushing’s disease, your veterinarian may also recommend a urinalysis and/or urine culture. These tests look for evidence of urinary tract infections, which can be “silent” and accompany Cushing’s disease, especially in female dogs.

How is Cushing’s disease in dogs treated?

Like my client who was concerned for her beloved senior dog, your next question may be, “What happens if my dog is diagnosed with Cushing’s?”

In most cases, Cushing’s is a lifelong disease. Treatment requires careful monitoring by your veterinarian. It is a commitment and it can be daunting. However, the good news is that there are many treatment and management options to help your dog feel better.

Medical treatment options for Cushing’s disease

Since over 80% of dogs diagnosed with Cushing’s disease have tumors in their brain that are very small, management with medication is usually the preferred route. Your veterinarian may prescribe medications such as the ones listed below.

Vetoryl and Lysodren

Vetoryl (trilostane) is currently the only veterinary-approved product on the market that treats both pituitary and adrenal-dependent forms of the disease. It blocks the production of cortisol to bring cortisol levels back to normal.

Another drug called Lysodren (mitotane) targets the adrenal glands, which are over-producing cortisol. This medication keeps the glands from producing as much cortisol.

For more information on how these medications work, please read this article by Veterinary Partner on treating the pituitary form of Cushing’s.

Dogs taking medications such as Vetoryl or Lysodren require close monitoring with frequent lab work. Sometimes these medications can work TOO well and cause the opposite condition—hypoadrenocorticism (aka Addison’s disease). Follow-up bloodwork with your veterinarian will be necessary.

In the interest of full disclosure, this can represent a significant financial and time commitment. When initially starting therapy and when making dose adjustments, your vet may need to run bloodwork as often as every few weeks or months.

Selegiline and off-label medications

Selegiline, a drug used to manage canine cognitive dysfunction, is also approved to treat the pituitary tumor form of Cushing’s disease. Also, there are other off-label medication options such as ketoconazole and melatonin for dogs. However, these are not approved and must be used with care and with the understanding that they may not be effective.

Surgical treatment for Cushing’s disease

If an adrenal tumor is the cause of the Cushing’s, the affected gland can be surgically removed. This is not a simple surgery and is ideally performed by a board-certified surgeon. Risk of hemorrhage from surgical removal of the gland is significant as is the risk of other post-operative complications. Thus, many pet parents opt to treat their dogs with medical management to avoid the cost and risk of surgery.

Is my dog in pain with Cushing’s?

Cushing’s disease doesn’t cause pain in dogs in the traditional sense of the word. It isn’t like a torn ACL in dogs or intervertebral disc disease (IVDD) in dogs. However, I would argue that it can negatively impact quality of life. Hear me out.

Dogs with uncontrolled Cushing’s disease are thirsty all the time and need to urinate frequently. Sometimes they may have accidents in the house if they can’t make it outside in time. That can be hard on a dog’s dignity. It may also be more difficult for them to rest peacefully since they are prone to panting and pacing.

We can’t know for sure the emotional impact those changes have on a dog, and I’ve seen hundreds of “untreated” Cushing’s patients over the years who seemed fine. However, living with symptoms of Cushing’s is not ideal for the dog nor their family. The good news, though, is that treating your dog’s Cushing’s disease will help get those symptoms under control. This can greatly improve your dog’s quality of life.

How to comfort a dog with Cushing’s disease

What can you do to help your beloved dog? In addition to treating your dog’s Cushing’s disease, here are more things you can do to be vigilant in managing your dog’s condition.

1. Always have fresh water available. As I mentioned, Cushing’s causes increased thirst and urination, so your dog will want to drink more and need to go out frequently for potty breaks. Make sure you refill the water bowl and giving your dog plenty of opportunities to go potty.
2. Keep a sharp eye on your dog’s skin. If you notice signs of skin infection such as bumps, crusts, hair loss, or red irritated skin, speak with your vet. It is important that skin infections are addressed promptly. In some cases, your vet may also prescribe antifungal and antibacterial shampoos and wipes to proactively help combat skin infections.
3. Watch for signs of urinary issues such as increased frequency of urination, foul odor to the urine, straining to urinate, and/or blood in the urine. If you observe any of these signs, take your dog to your veterinarian. For dogs with Cushing’s, urinary tract infections are nearly impossible to prevent. However, you can help your dog by seeking treatment promptly.
4. Keep in close contact with your veterinarian about any changes in your dog’s symptoms. If you notice vomiting, diarrhea, lethargy in dogs, tremors, or loss of appetite, contact your veterinarian immediately. These may be signs that your dog has flipped from Cushing’s disease (too much cortisol) to Addison’s disease (too little cortisol). Addison’s disease can be life threatening, so it is critical your dog gets veterinary attention right away.

Addressing mobility issues due to Cushing’s disease

If your dog is having mobility issues due to muscle wasting, look for options to minimize discomfort and falling. I recommend the following to many of my clients:

• Keep your dog on carpet.
• Avoid slick floors.
• Learn how to relieve arthritis pain in dogs.
• Choose a soft bed for your dog’s comfort. (Consider a memory foam dog bed.)
• If possible, avoid stairs.
• Consider laser therapy for dogs and physical therapy.
• Teach your dog to use ramps.
• Additionally, I’ve had many patients with muscle wasting due to Cushing’s syndrome thrive using ToeGrips® dog nail grips. The non-slip grips fit on dogs’ toenails to improve traction on hardwood floors, preventing sliding and falling.

As the founder of Dr. Buzby’s ToeGrips® dog nail grips, I often hear from customers who share success stories and leave positive ToeGrips® reviews. One of our customers wrote to let us know that her dog, Brew, a 14-year-old Bichon and Cavalier Spaniel with Cushing’s syndrome, saw an immediate improvement in his mobility with the addition of ToeGrips® dog nail grips.

Read Brew’s story:

Just under 24 hours of having the toegrips on and I must give a rave review. It really is amazing to see my boy get up off the floor on the first try! He (Brew) has Cushings Disease which makes him run a bit warmer than the average dog. So he minds the heat a lot, causing him to want to shift around and find new cold spots on the laminate floor. I was skeptical about these at first, not personally knowing anyone that has tried them, but seeing nothing but good reviews, I was hopeful. Well, here I am gushing. He is no longer doing a Bambi on ice I really hope anyone on the fence about these reads this and goes and gets them sooner than later.

I wish I had tried them sooner seeing just how good they work on my Brew. I would also like to say that the customer service from this company is amazing!!! Thank you Dr. Buzby and anyone else that helped to get this product in my home and on my dog. I will tell anyone that will listen to get these for their dog, and when my other dogs get old enough to need them, they will be getting them without a doubt! Thank you, Thank you, Thank you!!! —Crystal W.

What is the prognosis for dogs diagnosed with Cushing’s disease?

Cushing’s disease in dogs is not a hopeless diagnosis! But it IS a disease that requires careful and observant monitoring, both by you and your veterinarian.

What questions do you have about Cushing’s disease in dogs?

Please comment below.