In the final stages of Cushing’s disease, dogs typically experience a cascade of worsening symptoms as prolonged cortisol excess damages multiple organ systems. The signs most owners notice first are severe muscle wasting, an increasingly distended abdomen, recurring infections that won’t clear, and a general loss of interest in the activities their dog once loved. Understanding what happens in these late stages can help you recognize when your dog’s condition is progressing and make informed decisions about their comfort and care.
How the Body Breaks Down Over Time
Cushing’s disease floods the body with cortisol for months or years. Early on, the signs are manageable: increased thirst, frequent urination, a bigger appetite. But as the disease advances without adequate control, the damage compounds. Muscles weaken and waste away, especially in the hind legs, making it harder for your dog to stand, climb stairs, or go on walks. The classic “potbellied” appearance becomes more pronounced as abdominal muscles thin out and the liver enlarges.
Skin changes become increasingly severe in late-stage disease. The skin grows thin and fragile, bruises easily, and heals poorly. Hair loss that may have started as patchy thinning can progress to large bald areas across the trunk. Open sores and skin infections become common because the immune system, suppressed by all that excess cortisol, can no longer fight off bacteria effectively. Urinary tract infections also become frequent and harder to treat, sometimes becoming chronic.
Serious Complications in Advanced Disease
The most dangerous complications of late-stage Cushing’s are the ones that can develop suddenly. Dogs with Cushing’s are at elevated risk for blood clots, particularly in the lungs. A pulmonary thromboembolism can cause labored or rapid breathing, blue-tinged gums, coughing (sometimes with blood), collapse, and in some cases sudden death. This is one of the most serious and unpredictable risks in advanced disease.
Other complications that tend to appear as the disease progresses include diabetes, gallbladder disease, and high blood pressure. The weakened immune system leaves dogs vulnerable to infections that a healthy body would easily handle, and these infections can escalate to dangerous levels. Cornell University’s veterinary college lists urinary tract infections, skin infections, blood clots, seizures, sudden blindness, gallbladder disease, and diabetes among the conditions commonly associated with Cushing’s.
Neurological Signs From Pituitary Tumors
About 80 to 85 percent of canine Cushing’s cases are caused by a tumor on the pituitary gland at the base of the brain. In many dogs, this tumor stays small and the neurological effects are minimal. But in some cases, the tumor grows large enough to press on surrounding brain tissue, and this is when some of the most distressing late-stage symptoms appear.
A growing pituitary tumor can cause depression, disorientation, and loss of coordination. Dogs may walk in circles, press their heads against walls, or seem confused in familiar environments. Seizures can develop. If the tumor presses on the optic nerves, dogs can go blind, sometimes suddenly. These neurological signs often mark a significant turning point in the disease, because they indicate the tumor itself is becoming a problem beyond the hormonal imbalance it causes. Dogs with these symptoms are often described as depressed and uncoordinated, collapsing with exercise and losing weight.
What the Final Weeks Often Look Like
In the last stage of the disease, the signs you’ve been managing individually start to overlap and intensify. A dog who was already drinking excessively may begin having accidents indoors because weakened muscles make it impossible to hold urine. Appetite, once ravenous from the cortisol, may drop off as the dog feels increasingly unwell. Panting at rest becomes common. Energy levels fall dramatically, and your dog may spend most of the day sleeping or lying still.
The combination of muscle loss, recurring infections, poor wound healing, and possible neurological decline means that many dogs in the final stages need help moving around, can no longer keep themselves clean after soiling, and stop engaging with their family or surroundings the way they used to. Some dogs develop a dull, depressed demeanor that’s markedly different from their personality before illness. Weight loss accelerates despite whatever appetite remains.
Assessing Your Dog’s Quality of Life
One of the hardest parts of advanced Cushing’s is that the decline is often gradual, making it difficult to identify a single moment when things have clearly shifted. Veterinary quality-of-life tools can help bring some clarity to what you’re seeing day to day.
A practical approach recommended by veterinary programs is to track good days versus bad days on a calendar, even with something as simple as a happy or sad face for each day. When the bad days start to outnumber the good ones, it’s a meaningful signal. Another method is to write down three to five things your dog has always enjoyed, whether that’s greeting you at the door, going for a walk, chewing a favorite toy, or lying in a sunny spot in the yard. When your dog can no longer do or enjoy most of those things, the disease has likely eroded their quality of life beyond what management can restore.
Specific signs that veterinary teams consider significant include: your dog no longer wanting to play or interact with you, hiding, refusing food (or only eating treats hand-fed to them), panting while resting, trembling or shaking, inability to move around without help, chronic vomiting or diarrhea, and an overall demeanor that seems dull and unlike the dog you know. No single sign on its own necessarily means it’s time, but when several of these stack up together, they paint a picture that’s hard to ignore.
Why Treatment Becomes Harder Late in the Disease
The medications used to manage Cushing’s work by lowering cortisol production, but they carry their own risks that become harder to balance as a dog’s health deteriorates. Both common medications can cause decreased appetite, vomiting, diarrhea, and lethargy. In serious cases, they can destroy the adrenal gland entirely or cause dangerous electrolyte imbalances, which can be fatal. For dogs whose bodies are already fragile from advanced disease, the margin between a therapeutic dose and a harmful one narrows.
Surgical removal of an adrenal tumor, when that’s the cause, carries a 10 to 25 percent risk of death during or after the procedure. For pituitary tumors, surgery is rarely performed in dogs. Radiation therapy can sometimes slow the growth of large pituitary tumors causing neurological symptoms, but it’s not widely available and doesn’t reverse damage already done.
At a certain point, the goal of treatment shifts from controlling the disease to keeping your dog comfortable. This might mean managing pain, treating infections as they arise, helping with mobility, and ensuring your dog can eat, drink, and rest without distress. When even these comfort measures can no longer prevent suffering, many veterinarians and owners together reach the decision that euthanasia is the most compassionate choice remaining.