Cushing's disease creeps in so gradually that many owners chalk the early signs up to aging — the extra drinking, the pot belly, the thinning coat. Recognizing the pattern is what gets a dog diagnosed.
Cushing's disease (hyperadrenocorticism) is when a dog's body overproduces cortisol, causing increased thirst and urination, a pot-bellied appearance, hair loss, and increased appetite. It develops slowly and is often mistaken for normal aging. It's diagnosed with specific tests by your veterinary team and managed long-term with medication and monitoring a vet directs.
What Cushing's is
The opposite of Addison's — too much cortisol rather than too little. It usually comes from a small tumor on the pituitary or adrenal gland and mostly affects middle-aged and older dogs. [1]
The signs owners miss
Watch for much more drinking and peeing, a pot belly, thinning coat, more hunger, and panting. These are easy to blame on age, which delays diagnosis.
Diagnosis and management
Specific blood and urine tests confirm it. It's managed long-term with medication and regular monitoring under veterinary care. We never set doses; your vet does.
The disease that hides as "just aging"
Cushing's is the master of disguise: more drinking, more urinating, a pot belly, thinning coat, more panting — every one of which owners chalk up to an old dog getting older. That's exactly why it's so often caught late. If several of these are creeping in together, it's worth asking your vet specifically about Cushing's rather than accepting "he's just old."
What's actually going wrong
The body is making too much cortisol, usually from a small tumor on the pituitary or adrenal gland. It's the mirror image of Addison's (too little cortisol). It mostly affects middle-aged and older dogs, and some cases trace to long-term steroid use rather than a tumor.
Diagnosis takes specific testing
Here's the part: Cushing's can't be confirmed on symptoms alone or a single routine blood panel. It needs specific tests your vet runs, sometimes more than one, because false readings happen. That diagnostic care is worth it — treating for Cushing's when it isn't Cushing's causes harm.
Management is long-term
Once confirmed, it's managed with medication and regular monitoring under veterinary care, not a one-time fix. Many dogs do well with proper management. Treatment and dosing are directed by your vet; we never set doses.
The two types (and why it matters which one)
Cushing's isn't one disease. About 80-85% of cases are pituitary-dependent, driven by a small benign tumor on the pituitary gland that overstimulates the adrenals. The rest are adrenal-dependent, from a tumor on an adrenal gland itself. There's also iatrogenic Cushing's, caused by long-term steroid medication. Which type your dog has changes the testing, the treatment, and the outlook, so identifying it is a real part of the workup, not a technicality.
Why diagnosis takes more than one test
Here's the part most owners aren't told: there is no single perfect Cushing's test. Vets use screening tests (like the ACTH stimulation test or low-dose dexamethasone suppression test) plus bloodwork and urine, and sometimes imaging to find the tumor's location. False positives and negatives happen, which is why a diagnosis sometimes takes more than one visit. This diagnostic care is worth it, because treating a dog for Cushing's it doesn't have causes real harm.
What treatment actually involves
Most pituitary-dependent cases are managed with daily medication that controls cortisol production, alongside regular monitoring blood tests to keep the dose right. It's a long-term commitment, not a cure, but well-managed dogs often feel dramatically better, less thirst, more energy, a healthier coat. Adrenal-dependent cases may be candidates for surgery. Treatment and dosing are set and adjusted by your vet; we never set doses.
Living with a Cushing's dog
Day to day, expect more frequent vet rechecks (especially early on while the dose is dialed in), watching water intake and appetite as signs of control, and staying alert to infections, since Cushing's dogs are more prone to them. The reassuring reality: many dogs live well for years with managed Cushing's and often ultimately pass from unrelated age-related causes. It's a manageable chronic condition, not an immediate crisis.
Cushing's vs its opposite, Addison's
It's worth knowing that Cushing's (too much cortisol) has a mirror-image condition, Addison's disease (too little cortisol). They can look confusingly different, and in rare cases treatment of one can tip toward the other, which is another reason monitoring matters. If you've read about both and feel confused, that's normal, your vet keeps the balance right through regular testing.
Frequently asked questions about cushing’s disease in dogs
Is Cushing's disease curable?
Some cases (certain tumors) can be treated surgically; most are managed long-term with medication.
How is it different from Addison's?
Cushing's is too much cortisol; Addison's is too little. Opposite conditions.
Related endocrine conditions
Cushing’s symptoms · Cushing’s life expectancy · Addison’s disease · Hypothyroidism · Diabetes symptoms · Thyroid problems
Sources & References
For educational use. PrepperPetSupply is a licensed, veterinarian-staffed pharmacy; prescriptions are dispensed only after review by a licensed veterinarian and are not a substitute for in-person veterinary care. Not for human use.