When “Getting Older” Might Be Something More
As dogs age, it’s normal to notice some changes. Maybe your dog sleeps a little more, moves a bit slower, or seems less interested in activities they once loved.
But sometimes changes that appear to be part of normal aging can actually be signs of an underlying medical condition.
One of those conditions is Cushing’s disease in dogs, an endocrine disorder that often develops gradually over months or even years. Because the symptoms tend to appear slowly, many owners don’t realize anything is wrong until the changes become difficult to ignore.
In the Valley, this can be especially challenging. Increased thirst, excessive panting, or reduced energy are sometimes attributed to the summer heat. While weather certainly plays a role, persistent or progressive changes deserve veterinary attention.
This article explains what Cushing’s disease is, common symptoms to watch for, how veterinarians diagnose it, available treatment options, and how it differs from Addison’s disease in pets.
What Is Cushing’s Disease in Dogs?
Cushing’s syndrome, also called hyperadrenocorticism, occurs when a dog’s body is exposed to excessive amounts of cortisol over time.
Cortisol is a hormone produced by the adrenal glands. It plays an important role in regulating metabolism, responding to stress, controlling inflammation, and maintaining normal body functions.
When cortisol levels remain too high for too long, the hormone begins to affect multiple body systems, leading to a wide variety of symptoms.
The term “Cushing’s disease” is commonly used to describe the condition, although technically it most often refers to the pituitary-dependent form of hyperadrenocorticism.
What Causes Cushing’s Disease in Dogs?
There are three primary causes of Cushing’s disease.
Pituitary-Dependent Cushing’s
This is the most common form.
A small tumor in the pituitary gland causes excessive stimulation of the adrenal glands, leading to increased cortisol production.
Most pituitary tumors associated with Cushing’s disease are benign, but they can still significantly affect hormone regulation.
Adrenal-Dependent Cushing’s
In some dogs, a tumor develops within one of the adrenal glands.
This tumor may cause the gland to produce excessive cortisol regardless of the body’s normal need for cortisol.
Some adrenal tumors are benign, while others can be malignant.
Iatrogenic Cushing’s
This form occurs when a dog receives long-term steroid medications that mimic the effects of cortisol.
Steroids can be valuable and sometimes lifesaving medications, but prolonged use may lead to signs similar to naturally occurring Cushing’s disease.
Common Symptoms of Cushing’s Disease in Dogs
Cushing’s affects multiple organ systems, which is why symptoms can seem unrelated at first.
Common signs include:
Increased Thirst
Many owners first notice that water bowls need refilling more often than usual.
Increased Urination
Dogs may need more frequent bathroom breaks or begin having accidents in the house despite previous housetraining.
Increased Appetite
Many dogs with Cushing’s seem unusually hungry and may beg for food more frequently.
Excessive Panting
Panting may occur even while resting in air-conditioned environments.
Pot-Bellied Appearance
Muscle weakness combined with fat redistribution can create a characteristic rounded abdomen.
Muscle Weakness
Dogs may struggle with stairs, jumping into vehicles, or rising from lying down.
Lethargy
Energy levels often decrease gradually over time.
Heat Intolerance
Dogs may seem less able to tolerate warm temperatures than they once could.
Hair Loss or Thinning Coat
Hair may become thin, particularly on the body while the head and legs remain relatively normal.
Thin or Fragile Skin
Skin can become more delicate and prone to injury.
Recurrent Skin or Urinary Tract Infections
Chronic cortisol elevation can affect immune function, making infections more common.
When Symptoms Are Subtle
One of the challenges of Cushing’s disease is that many affected dogs still seem relatively happy.
They may continue eating well, enjoying family interactions, and participating in daily routines.
Because the disease often progresses slowly, changes can be easy to overlook.
A dog that drinks a little more water this month may be drinking significantly more six months later—but the gradual progression makes it difficult to recognize.
This is one reason routine wellness exams and annual bloodwork are so valuable.
How Vets Diagnose Cushing’s Disease in Dogs
Diagnosing endocrine (hormonal) diseases is rarely as simple as running one test.
Veterinarians combine your dog’s history, physical examination findings, laboratory results, and hormone testing to arrive at a diagnosis.
Physical Exam and History
Your veterinarian will discuss:
- Changes in thirst and urination
- Appetite changes
- Activity levels
- Weight changes
- Skin or coat concerns
- Current medications
Baseline Laboratory Testing
Bloodwork and urinalysis help identify abnormalities commonly associated with Cushing’s disease and may reveal other conditions causing similar symptoms.
Hormone Testing
Specialized endocrine tests are necessary to diagnose Cushing’s diease.
Common examples include:
- Low-dose dexamethasone suppression testing (LDDST)
- ACTH stimulation testing
Importantly, Cushing’s disease typically cannot be confirmed with a single routine cortisol measurement.
Acute illness, stress, and other medical conditions can influence hormone results, which is why testing must always be interpreted alongside the patient’s overall clinical picture.
Imaging and Specialist Consultation
Abdominal ultrasound, advanced imaging, or consultation with an internal medicine specialist may be recommended to identify adrenal tumors or further evaluate complicated cases.
Learn more about our Internal Medicine team:
https://1stpetvet.com/specialty-referral-services/internal-medicine/
Treatment Options for Cushing’s Disease in Dogs
Treatment depends on several factors, including:
- The type of Cushing’s disease
- Severity of symptoms
- Other medical conditions
- Your dog’s age and overall quality of life
Medication Management
Many dogs are successfully managed with medication that helps regulate cortisol production.
Regular monitoring is essential because hormone levels can change over time.
Surgery in Select Cases
Some adrenal tumors may be candidates for surgical removal.
These cases often require advanced diagnostics and specialist evaluation.
Monitoring and Long-Term Care
Cushing’s disease is typically a long-term condition requiring ongoing monitoring.
Follow-up testing helps ensure treatment remains both safe and effective.
Cushing’s Disease vs. Addison’s Disease in Pets
Because both conditions involve the adrenal glands, owners often hear them discussed together.
However, they are essentially opposite hormone disorders.
The Simple Difference
Cushing’s disease involves too much cortisol activity.
Addison’s disease involves too little adrenal hormone activity.
How the Signs Differ
Cushing’s Disease May Cause:
- Increased thirst
- Increased urination
- Increased appetite
- Excessive panting
- Pot-bellied appearance
- Hair loss
- Skin changes
- Recurrent infections
Addison’s Disease May Cause:
- Lethargy
- Vomiting
- Diarrhea
- Weight loss
- Poor appetite
- Weakness
- Intermittent illness
- Collapse in severe cases
Why Addison’s Can Be Urgent
Unlike Cushing’s disease, Addison’s disease can sometimes progress to a life-threatening emergency known as an Addisonian crisis.
Dogs experiencing an Addisonian crisis may develop:
- Severe weakness
- Collapse
- Shock
- Significant dehydration
- Persistent vomiting
- Severe diarrhea
These situations require immediate veterinary care.
Can Treatment for Cushing’s Cause Addison’s-Like Problems?
In some cases, medications used to manage Cushing’s disease can suppress adrenal function too much.
If this occurs, dogs may develop symptoms resembling Addison’s disease.
This is one reason routine monitoring is so important throughout treatment.
When Should You See a Vet?
Schedule an Appointment If:
- Your dog is drinking more than usual
- Urination has increased
- Panting has become more frequent
- Appetite has increased significantly
- A pot-bellied appearance develops
- Hair is thinning
- Skin infections continue recurring
- Changes seem progressive over time
Seek Urgent or Emergency Care If:
- Your dog collapses
- Severe vomiting or diarrhea develops
- Your dog becomes profoundly weak
- Signs of dehydration occur
- Breathing becomes labored
- Pale gums develop
- Your dog is receiving endocrine medication and suddenly appears very ill
How 1st Pet Can Help
At 1st Pet Veterinary Centers, our primary care veterinarians and internal medicine specialists work together to diagnose and manage complex endocrine diseases, including Cushing’s disease and Addison’s disease.
Whether your dog is showing early signs or needs advanced diagnostic testing, our team can help guide you through every step of the process.
Learn more:
Frequently Asked Questions
Is Cushing’s disease in dogs curable?
It depends on the cause. Some adrenal tumors may be candidates for surgery, while many dogs are successfully managed with medication and ongoing monitoring.
How do vets test for Cushing’s disease?
Testing often includes bloodwork, urinalysis, endocrine testing such as ACTH stimulation or low-dose dexamethasone suppression testing, and imaging when appropriate.
Is Addison’s disease an emergency?
It can be. Severe weakness, collapse, dehydration, vomiting, diarrhea, or shock-like symptoms require urgent veterinary care.
Should I stop my dog’s steroid medication if I’m worried about Cushing’s?
No. Steroid medications should never be stopped abruptly without veterinary guidance. Contact your veterinarian if you have concerns about side effects or possible Cushing’s disease.
Final Thoughts
Cushing’s disease often develops gradually, making it easy to mistake for normal aging.
Increased thirst, increased appetite, excessive panting, and subtle changes in energy level may not seem dramatic at first—but they can be important clues that something deeper is happening.
The good news is that many dogs with Cushing’s disease can enjoy an excellent quality of life when the condition is recognized early and managed appropriately.
If your dog’s habits, appearance, or behavior seem to be changing, don’t assume it’s simply age. A veterinary evaluation can help determine whether those changes are normal—or whether they’re signs of an endocrine condition that deserves attention.