Cushing’s disease in dogs—also called Cushing’s syndrome or hyperadrenocorticism—is a medical condition caused by prolonged exposure to excess cortisol. In many cases, this excess cortisol is produced within the body. However, the cortisol can also come from an external source (such as medications).
Cushing’s disease can occur in both dogs and cats, although it is significantly more common in dogs.
What is Cushing’s Disease?
Cushing’s disease occurs as a result of excess cortisol circulating within a dog’s body.
Cortisol is a hormone that is produced by the adrenal glands (two small glands in the abdomen) during times of stress. The actions of cortisol are actually beneficial during stress—cortisol helps mobilize fat and sugar to increase available energy, helps the body retain water, and performs other important functions.
If cortisol is released constantly or in excessive quantities, however, these beneficial effects can become harmful. Chronic cortisol exposure leads to changes in metabolism, changes in fluid balance, the breakdown of muscle tissue, and even decreased immune system function.
Cushing’s disease is most commonly diagnosed in older dogs. While the condition itself is not usually fatal in the short-term, untreated Cushing’s disease is associated with complications that can be fatal. Additionally, some cases of Cushing’s disease are caused by adrenal cancer, which can be fatal if untreated.
What Causes Cushing’s Disease in Dogs?
Cushing’s disease is divided into three categories, each of which has a unique cause:
Pituitary-dependent: A benign tumor in the pituitary gland (within the brain) leads to overproduction of adrenocorticotropic hormone (ACTH), the hormone responsible for stimulating the adrenal glands to produce cortisol. Most cases of Cushing’s disease (approximately 80-85 percent) are pituitary-dependent.
Adrenal-dependent: A tumor in one of the adrenal glands results in overproduction of cortisol.
Iatrogenic: Long-term treatment with steroids (such as prednisone) causes Cushing’s disease.
Cushing’s disease can occur in dogs of any breed, but some breeds are diagnosed more frequently than others.
Dog breeds prone to Cushing’s disease include:
- Boston Terriers
- Miniature Schnauzers
Symptoms of Cushing’s Disease
The clinical signs of Cushing’s disease are similar to those expected in a person who is taking long-term cortisol.
Affected dogs demonstrate behavior changes, with a tendency to eat and drink more than usual. Because they are drinking more, these dogs also urinate more often than usual. They may gain weight, developing a pot-bellied appearance.
Other symptoms of Cushing’s disease in dogs include:
- Increased panting
- Muscle weakness
- Hair loss (often symmetrical, affecting both sides of the trunk)
- Darkening of the skin
- Thinning of the skin
- Other skin/coat changes
Diagnosing a Dog With Cushing’s Syndrome
In most cases, diagnosing a dog with Cushing’s disease is a multi-step process. A veterinarian typically begins with screening tests, which indicate whether Cushing’s disease is a likely possibility and determines whether further Cushing’s testing is necessary.
If screening tests suggest a high likelihood of Cushing’s disease, a veterinarian then performs diagnostic tests to determine whether or not the dog has Cushing’s disease. Even after a diagnosis of Cushing’s disease, additional testing may be required to distinguish pituitary-dependent from adrenal-dependent Cushing’s disease.
Screening Tests for Cushing’s Disease
Basic laboratory tests. First, veterinarians will likely perform a complete blood cell count, serum biochemistry, and urine tests. Dogs with Cushing’s disease often have characteristic changes in their bloodwork, including an increase in a liver enzyme called alkaline phosphatase, increased cholesterol and triglycerides, increased blood sugar, and increased platelets. On urinalysis, affected dogs often have dilute urine and increased urine protein levels. These findings suggest a need for further testing.
Urine cortisol/creatinine ratio (UCCR): This test looks for cortisol in the urine. If a dog’s first morning urine has low/normal levels of cortisol, Cushing’s disease is very unlikely and no further testing is recommended. Elevated cortisol in the urine is often (but not always) associated with Cushing’s disease. Therefore, elevated urine cortisol indicates a need for further testing.
Diagnostic Tests for Cushing’s Disease
There are two tests used to diagnose Cushing’s disease. Each test has unique pros and cons.
ACTH stimulation test: In this test, blood is drawn before and after administering an injection of ACTH. This hormone should trigger the release of cortisol, but an exaggerated response to ACTH stimulation suggests Cushing’s disease. The primary advantage to using ACTH stimulation as a diagnostic test is that it can be performed quickly. Dogs only need to be hospitalized for one hour to complete this diagnostic test.
Low-dose dexamethasone suppression test (LDDS): In this test, blood is drawn before and after the administration of an injection of dexamethasone (a steroid that is similar to cortisol). A normal dog should stop producing cortisol when given a dexamethasone injection, while a dog with Cushing’s disease will keep producing cortisol. Unlike the ACTH stimulation test, this test takes 8 hours to perform. On the plus side, however, this test is less expensive.
After a pet is diagnosed with Cushing’s disease, additional testing may be required to distinguish between pituitary-dependent and adrenal-dependent disease.
In dogs diagnosed using the LDDS test, the results often provide the ability to differentiate between pituitary-dependent and adrenal-dependent Cushing’s disease.
In dogs receiving the ACTH stimulation test, or in which the LDDS did not differentiate between the two types of Cushing’s disease, additional testing will be required.
Differentiating tests include a high-dose dexamethasone suppression test (HDDS), endogenous ACTH level, or an abdominal ultrasound. Your veterinarian will recommend any additional testing needed to properly diagnose the type of Cushing’s disease in your dog.
How to Treat and Manage Cushing’s Disease in Dogs
The treatment of Cushing’s disease depends on which type is present.
Dogs with adrenal-dependent Cushing’s disease are typically treated with an adrenalectomy, which is the surgical removal of the adrenal gland. This treatment should permanently resolve the signs of Cushing’s disease. Unfortunately, this treatment is not without risk.
Adrenalectomy is typically performed by a veterinary surgeon, at a referral hospital or veterinary teaching hospital. Dogs receive a thorough pre-anesthetic workup prior to surgery and may also be started on medications to minimize the risk of complications.
Adrenalectomy is performed under general anesthesia. The surgeon will make an incision in the abdomen and remove the affected adrenal gland. After surgery, dogs are monitored in the intensive care unit (ICU) for at least 24 hours. This allows for the early detection and treatment of surgical complications, such as blood clots.
Medications Used to Treat Cushing’s Disease in Dogs
Medical treatment is recommended for pets with pituitary-dependent Cushing’s disease. There are two medications commonly used to treat Cushing’s disease: trilostane and mitotane.
Trilostane: This medication temporarily blocks the production of cortisol. It is administered once or twice daily for the remainder of the pet’s life.
Mitotane: This drug works by permanently killing cortisol-producing cells within the adrenal gland. Pets treated with mitotane typically undergo 7-10 days of induction (daily dosing), then are maintained on a once-weekly dose of medication. Because mitotane has irreversible effects on the adrenal gland, this is often considered to be a riskier treatment than trilostane.
Dogs with Cushing’s disease typically receive one of these medications for the rest of their life. Treatment with trilostane or mitotane requires extensive monitoring.
Regular ACTH stimulation tests should be performed to assess adrenal function, in addition to monitoring complete blood cell count, serum biochemistry, and urinalysis.
How Long Can a Dog Live With Cushing’s Disease?
The prognosis for dogs with pituitary-dependent Cushing’s disease is good. With appropriate treatment, survival times of 2-3 years are typically reported.
The prognosis for dogs with adrenal-dependent Cushing’s disease can be divided into two periods: the surgical period and long-term. The prognosis for surgery is guarded, since it is a risky procedure that can have complications. If surgery is successful, however, these dogs also have a good long-term prognosis, with a mean survival time of 3 years.
General Cost of Treatment
Diagnosing and managing Cushing’s disease in dogs can be expensive and pet parents should prepare for the financial costs of surgery or lifelong medications.
While rates vary by location, pet owners can expect to spend the following to diagnose and treat Cushing’s disease.
- Diagnostic testing: $500-$1,000
- Medication/monitoring: $1,500-$3,000 the first year, followed by $1,000-$2,000/year long-term
- Adrenal tumor removal: $2,000-$5,000 (only to be considered for dogs with adrenal-dependent Cushing’s disease)
How to Prevent Cushing’s Disease in Dogs
There is no known way to prevent adrenal-dependent or pituitary-dependent Cushing’s disease in dogs. Diet changes are not beneficial in preventing or treating this condition.
Iatrogenic Cushing’s disease, however, can be prevented. Limiting a dog’s exposure to steroids will prevent iatrogenic Cushing’s disease. Steroids can be found in some over-the-counter topical medications, so these medications should be used with caution.
Dogs with chronic skin allergies and other inflammatory conditions should be managed with nonsteroidal therapies, when possible.
- Addison’s Disease
What can I do to help my dog with Cushing's disease? ›
Most veterinarians treat both adrenal- and pituitary-dependent Cushing's disease with medication. The only way to "cure" Cushing's disease is to remove the adrenal tumor if the disease is adrenal-dependent and the tumor hasn't spread, says Stohlman.How long do dogs usually live with Cushing's disease? ›
According to the American Kennel Club the average survival time for a dog with Cushing's is about two years, with only 10 percent living beyond the four-year mark. That said, it's important to remember that most cases of Cushing's disease are diagnosed in elderly dogs.Is there a natural way to treat Cushing's disease in dogs? ›
A combination of Melatonin and Lignans offer an excellent natural treatment for both Cushing's and Atypical Cushing's disease in dogs. In fact, supplementing with melatonin and lignans helps your dog's system return to normal.Is it worth it to treat Cushing's disease in dogs? ›
Statistically, treatment for Cushing's disease may help decrease the incidence of gall bladder disease in 26.6% of patients. Hypertension and proteinuria improved in 47% with treatment, and 60-80% in other references. All other comorbidity improvement is anecdotal or not likely to help with treatment.What foods should dogs avoid with Cushing's disease? ›
First and foremost, avoid feeding your dog table scraps and treats that are fatty or high in sugar, and instead follow your veterinarian's recommendations to find the right Cushing's disease diet for your dog.What foods should you avoid with Cushing's disease? ›
Slow down with the salt
Excess cortisol from Cushing's syndrome can increase blood pressure, leading to hypertension. Avoid processed foods packed with sodium, which contributes to high blood pressure. Focus on fruits, vegetables, and reduced-sodium soups, dressing, and spreads.
As the disease progresses, dogs lose muscle and become weak. Owners might notice a thinning of the skin, lesions on the skin, and hair loss on the flanks, neck, and perineum. Obesity and lack of energy are also symptoms.Do dogs with Cushings suffer? ›
Most dogs with Cushing's are not in any pain and their symptoms can be easily managed through medication. Dogs that have developed the condition due to a tumor on the adrenal gland may require the tumor to be surgically removed as these tumors are aggressive.Do dogs suffer when they have Cushing's disease? ›
While not inherently painful, Cushing's d isease in dogs (especially if uncontrolled) can be associated with: High blood pressure. Kidney infections. Bladder stones.Why did my dog get Cushing's disease? ›
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.
How does a dog with Cushing's feel? ›
The increased appetite is a direct result of elevated levels of cortisol, which stimulate appetite. Lethargy (drowsiness or lack of activity) and a poor hair coat are also common in pets with hyperadrenocorticism. "Many dogs with Cushing's disease develop a bloated or pot-bellied appearance."Why do dogs with Cushing's Lick? ›
Your dog may have Cushing's disease or Hyperadrenocorticism, in which his adrenal gland produces excessive glutocortisoid which can harm or affect many organs in the body such as the kidney and liver. It is also known to cause the excessive floor licking. Liver failure also causes this weird licking habit.Do dogs with Cushing's have anxiety? ›
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.Should you withhold water from a dog with Cushings? ›
You must continually monitor your dog's food and water intake. Both should return to a normal level. Water intake should be less than 1 ounce per pound (66 ml per kilogram) of body weight per day, but do not limit the water if your dog needs to drink more.What is the best food to feed a dog with Cushing's disease? ›
Dogs with Cushing's do best on a diet based on a highly digestible protein. Protein helps to prevent muscle wasting, a common side effect of Cushing's disease. Some examples of highly digestible protein sources include egg whites, beef, chicken, lamb, salmon, and organ meats.Should you treat an older dog with Cushing's disease? ›
Usually treatment for Cushing's is not even recommended unless the dog has clinical signs because treatment does not necessarily change their overall life span - it just keeps them from being polyuric (urinating a lot), polydypsic (drinking a lot), losing their hair, etc.How do you reduce cortisol in dogs? ›
Studies show that another supplement, Phosphatidylserine, derived from lecithin, may support hypothalamo‐pituitary‐adrenal function and help reduce cortisol levels naturally. Ask your holistic vet about giving this to your dog.What brings on Cushings? ›
Cushing syndrome occurs when your body has too much of the hormone cortisol over time. This can result from taking oral corticosteroid medication. Or your body might produce too much cortisol.Why do dogs with Cushing's pant at night? ›
The basis for increased panting in dog's with Cushing's disease is multifactorial. First, Cushing's disease results in increased fat deposits in the abdominal cavity and around the chest. Second, an increase in liver size impedes the diaphragm from being able to expand with ease.Why do dogs with Cushing's shake? ›
Too little cortisol production leads to a myriad of clinical signs including weakness, vomiting, lethargy, shaking, and even total collapse. The good news is your dog can recover, and often in a short period of time.
What happens if you don't treat Cushing's in dogs? ›
If Cushing's disease is left untreated, dogs tend to become progressively lethargic and weak. They have an increased susceptibility to contracting infections (particularly urinary infections) and the skin is slow to heal after any injury. Osteoporosis has been reported.How expensive is it to treat Cushing disease in dogs? ›
$500 to $1,500 is considered typical for a complete diagnosis (though the low end of this estimate would not include an ultrasound). Medical treatment can be as low as $50 a month or as high as $200, depending on the dog's response to treatment and the drug selected.
The overuse of steroids causes some cases of Cushing's. Female dogs are more prone to adrenal tumors than male dogs, and poodles, dachshunds, and Boston terriers are diagnosed with Cushing's more than other dog breeds.Does Cushing's affect dogs eyes? ›
Cushing's disease in dogs is associated with a number of ophthalmologic abnormalities, including corneal abnormalities (such as corneal degeneration and ulceration), keratoconjunctivitis sicca, lipemia of the aqueous humor and/or retina, and hypertensive chorioretinopathy.Do dogs with Cushings have trouble walking? ›
Dogs with Cushing's syndrome commonly develop muscle weakness. They begin to demonstrate difficulty doing ordinary feats such as, rising for lying down, climbing of stairs, jumping onto the couch, or inability to get into the car. Muscle weakness may cause the animal to gain a pot belly.Do dogs with Cushing's smell? ›
Some dogs with allergies or hormonal conditions, like Cushing's disease, have oilier skin, says Znajda. That oil can be a breeding ground for bacteria, which can make your pet smell a little funky, she says.How long can a dog live on Trilostane? ›
Survival times of dogs treated with trilostane or Lysodren are similar (about 600-900 days).Do dogs with Cushing's have itchy skin? ›
Hyperadrenocorticism (Cushings disease) due to an excess of cortisol production frequently causes the dog to itch, lose hair, have thin skin with dark pigment, drink excessively and have recurring skin problems.Does Cushing's disease in dogs cause incontinence? ›
The dog may begin leaking urine. Also, a urinary tract infection may be present.
Pituitary gland tumor.
The most common cause of Cushing's disease (85% - 90% of all cases) is a tumor of the pituitary gland (which is located at the base of the brain). The tumor may be either benign (harmless) or malignant (cancerous).
What are the symptoms of end stage Cushings disease in dogs? ›
- Excessive panting.
- Muscle weakness due to muscle atrophy.
- Pot-bellied appearance.
- Heat intolerance.
- Increased thirst and increased urination.
- Increased incidence of urinary tract infections.
- Alopecia (hair loss)
Because it takes time — at least one year — for these symptoms to develop, and because the symptoms are often mistaken for common signs of aging, many dogs have the advanced form of CD before the owner even recognizes a problem exists.Is Cushings a dog terminal? ›
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.When should a dog with Cushings be put down? ›
Dog's diagnosed with it tend to have an average lifespan of 2-3 years. If your dog's condition has been diagnosed at a later stage, is not improving despite medication, is in constant pain, or has started having a neurological impact on its health, it is time to make that tough decision to euthanize them.