TL; DR: Cushing’s disease can be difficult to recognize in dogs. Symptoms vary from one dog to the next and are often mistaken for natural aging. The most common signs are increased thirst and urination, increased appetite, excessive panting, a pot-bellied appearance, muscle weakness, and changes to the skin or coat.
Cushing’s disease develops when a dog’s body produces too much cortisol, a hormone that helps regulate stress, metabolism, immunity, and sleep. Over time, excess cortisol disrupts how body and organ systems function, leading to serious secondary conditions.
Before you chalk your dog’s health and behavioral changes up to age, learn which symptoms may deserve a second look.
Excessive amounts of cortisol over an extended period of time lead to hyperadrenocorticism, more commonly known as Cushing’s disease.
Most naturally occurring cases of Cushing’s are pituitary-dependent or caused by tumors on the pituitary gland. In healthy dogs, the pituitary gland helps control the adrenal glands, which produce cortisol. A pituitary tumor can cause the adrenal glands to produce excessive amounts of cortisol.
Less common is adrenal-dependent Cushing’s, which occurs when cortisol overproduction is triggered by a tumor on the adrenal gland.
Some causes of Cushing’s aren’t related to tumor growth. Iatrogenic Cushing’s is associated with the prolonged use of corticosteroid medications. Unlike the adrenal and pituitary-dependent forms, iatrogenic Cushing’s usually resolves once dogs taper off the medication.
Symptoms of Cushing’s DiseaseCushing’s disease can be subtle and doesn’t always announce itself with a distinctive collection of symptoms. Instead, pet parents may notice one small change at a time.
Your dog may begin emptying their water bowl more frequently, asking to go outside more often, or having accidents in the house.
Changes in drinking and toileting habits don’t automatically point to Cushing’s (and can also be symptoms of other conditions like UTIs, kidney disease, and diabetes), but they may be part of a larger symptom picture.
Dogs with Cushing’s may develop a noticeably increased appetite. A dog who has always been enthusiastic about mealtime may suddenly seem ravenous, beg more frequently, or act as though they are never satisfied.
Food obsession may seem like a behavioral issue, but sudden changes are worth bringing up to your vet.
If your dog is panting even when the weather is cool and they haven’t been exercising, take note.
Panting can have many explanations, including anxiety, pain, and respiratory illness, but it may point to Cushing’s in the presence of other symptoms.
Over time, excess cortisol can contribute to muscle loss and changes in the way fat is distributed throughout the body. This can give a dog a distinctly rounded belly.
Weight gain is easy to overlook in older dogs, but pay attention when it’s accompanied by weakness, fatigue, and loss of muscle tone.
Symmetrical hair loss, thin or fragile skin, dark patches, and slow-healing wounds are telltale signs of Cushing’s.
These symptoms can look a lot like seasonal allergies or other dermatological conditions, but don’t ignore skin or coat problems that keep returning despite treatment.
One of cortisol’s most important jobs is immune system regulation. A long-term excess of cortisol can impact your dog’s ability to fight off everyday viruses and bacteria.
If your dog has been under the weather more than usual or is suffering from frequent skin infections or UTIs, it’s a good idea to investigate their immune function.
Cushing’s disease affects much more than a dog’s appetite, thirst, or appearance. Over time, consistently elevated cortisol puts stress on multiple body systems and increases the risk of other health problems.
Dogs with untreated Cushing’s may be more susceptible to:
Not every dog with Cushing’s will develop secondary complications, but the risks are one reason early recognition and appropriate management matter. If you notice symptoms that aren’t resolving with other treatment, it’s worth scheduling an exam with your vet.
Diagnosis starts with bloodwork and a urinalysis. These tests don’t diagnose Cushing’s by themselves, but they do help your vet determine whether Cushing’s is probable and rule out other conditions.
From there, specific endocrine testing may be recommended. One commonly used test is the low-dose dexamethasone suppression test (LDDST), which evaluates how your dog’s body responds to a synthetic corticosteroid. Healthy dogs will reduce their natural cortisol production in the presence of the synthetic, while dogs with Cushing’s will continue to produce an excess.
Stress and co-occurring illnesses can make diagnosing Cushing’s challenging, but reporting all the symptoms you notice (however subtle) will help your vet get a full clinical picture.
Treatment depends on what’s causing the excessive cortisol production and your dog’s overall health.
For many dogs with naturally occurring Cushing’s, medication is used to control cortisol production. Dogs receiving treatment need to be closely monitored to make sure excessive cortisol is controlled without suppressing it too much.
If Cushing’s is caused by an adrenal tumor, surgery may be an option. Treatment decisions depend on factors such as the size and location of the tumor, whether it is malignant (cancerous), and the dog’s overall health.
Dogs with iatrogenic Cushing’s require a different approach. If a corticosteroid is causing the condition, your veterinarian may gradually taper your dog off the medication and watch for improvement. Be aware that steroids should never be discontinued suddenly without veterinary guidance.
One unusually thirsty day or an occasional bout of heavy panting shouldn’t send you into a panic, but persistent or progressively worsening changes deserve attention.
Take note of anything out of the ordinary, and make an appointment if you notice multiple hallmarks of Cushing’s, like:
Each of these symptoms has multiple alternative explanations, but it’s important not to dismiss them or assume they are an unavoidable part of aging.
If you’re concerned about noticeable changes in your dog’s health or behavior, your veterinarian can help find a medical explanation and make a plan to give your dog the best quality of life possible.
At Falls Village Veterinary Hospital, a Raleigh, NC veterinarian, dogs, cats & their families deserve the best. In fact, we specialize in delivering warm, compassionate care that reminds our clients and patients how unique and important they truly are. We provide complete veterinary care including dentistry, laser therapy, surgery, and more. Call us today!
