Most cases of Cushing’s disease in dogs are caused by a tumor on the pituitary gland or adrenal gland, and there is no known way to prevent these from developing. That’s a frustrating answer, but it’s the honest one. What you can do is prevent the one form that is avoidable (iatrogenic Cushing’s, caused by steroid medications), know which dogs are at highest risk, and catch the disease early enough that treatment is far more effective.
Why Most Cushing’s Cases Can’t Be Prevented
About 80 to 85 percent of Cushing’s cases in dogs are pituitary-dependent, meaning a small tumor on the pituitary gland at the base of the brain signals the adrenal glands to overproduce cortisol. The remaining naturally occurring cases come from a tumor on one of the adrenal glands themselves. Neither type has a known dietary, environmental, or lifestyle trigger you can control. There is a genetic component, with certain breeds at higher risk, but no screening test or breeding protocol currently exists to eliminate that risk.
This means prevention efforts are really about two things: avoiding the one preventable form of the disease, and detecting the others as early as possible so your dog gets treatment before serious complications set in.
Preventing Iatrogenic Cushing’s From Steroids
The one form of Cushing’s you can actively prevent is iatrogenic hyperadrenocorticism, which results from chronic excessive administration of steroid medications like prednisone or prednisolone. Dogs are commonly prescribed these drugs for allergies, immune disorders, inflammatory bowel disease, and joint problems. When given at high doses or for extended periods, exogenous steroids flood the body with cortisol and produce the same symptoms as a tumor-driven case: increased thirst, weight gain, hair loss, and a distended belly.
If your dog needs steroids for a legitimate condition, there are several things to keep in mind. After two weeks or more of use, the dose should be tapered to an every-other-day schedule. This allows the body’s own adrenal glands to remain active rather than shutting down in response to the external cortisol supply. Over time, daily steroid use causes the adrenal glands to atrophy. If the medication is then stopped suddenly, the dog can’t mount its own stress response, potentially triggering a dangerous blood sugar crisis.
Never abruptly discontinue a steroid your dog has been taking for more than a couple of weeks. Always expect and follow a tapering schedule from your veterinarian. And if your dog is on long-term steroids for a chronic condition, ask whether a lower dose, an alternative drug, or a non-systemic option (like a topical or inhaled steroid) could reduce total cortisol exposure.
Breeds With the Highest Risk
Cushing’s disease is most common in middle-aged and older dogs, typically appearing after age six. Certain breeds carry a genetic predisposition to the pituitary-dependent form, particularly smaller breeds. According to Cornell University’s College of Veterinary Medicine, breeds at elevated risk include Bichon Frises, Border Terriers, Jack Russell Terriers, and several other small to mid-sized breeds.
Larger breeds are not immune, but they’re more likely to develop the adrenal tumor form when they do get the disease. If you own a predisposed breed, the most useful thing you can do is stay alert to subtle early changes as your dog ages, since early detection is the closest thing to prevention once the disease process has started.
Recognizing Early Signs
Cushing’s disease develops slowly, and the early signs are easy to dismiss as normal aging. The FDA notes that the most common early symptoms include increased thirst, increased urination, and increased appetite. Many owners first notice that their dog is draining the water bowl faster than usual or asking to go outside more often. A dog that suddenly seems ravenous at mealtimes, despite gaining weight, is showing a classic pattern.
As the disease progresses, you may notice reduced activity, excessive panting (even at rest or in cool temperatures), thinning or fragile skin, hair loss, recurrent skin infections, and an enlargement of the abdomen that gives the dog a pot-bellied appearance. That belly isn’t fat in the usual sense. It’s a combination of liver enlargement, fat redistribution, and weakened abdominal muscles caused by sustained cortisol excess.
Any one of these signs on its own could have a dozen explanations. But when two or three appear together in a middle-aged or older dog, especially a predisposed breed, it’s worth asking your vet to run a cortisol screening test. The earlier Cushing’s is identified, the sooner treatment can begin and the less damage excess cortisol does to the liver, kidneys, and skin over time.
Reducing Long-Term Cortisol Exposure
While you can’t prevent tumor growth, you can take steps to support your dog’s overall hormonal health and reduce unnecessary cortisol exposure. Chronic stress elevates cortisol naturally. Dogs dealing with ongoing anxiety, pain from untreated arthritis, or environmental stressors produce more cortisol than relaxed, comfortable dogs. Addressing these issues won’t prevent a pituitary tumor, but it reduces the overall cortisol burden on the body.
Maintaining a healthy weight matters too. Obese dogs have altered hormonal signaling across multiple systems, and carrying excess weight makes it harder to spot the early abdominal changes that could signal Cushing’s. Regular vet visits with bloodwork become especially important once your dog reaches middle age. Routine blood panels can sometimes reveal elevated liver enzymes or other markers that prompt a vet to investigate cortisol levels before obvious symptoms appear.
The bottom line is straightforward: be cautious with steroid medications, know your dog’s breed-specific risks, and pay attention to gradual changes in thirst, appetite, energy, and body shape as your dog ages. You may not be able to stop Cushing’s from developing, but you can catch it early and avoid the one form that’s entirely within your control.