Some owners decide not to treat, and it is a far more common decision than the internet suggests. It is rarely made carelessly. It is made by people with a fourteen-year-old dog and a heart murmur, or a diagnosis that arrived the same month as a job loss, or a veterinarian who said honestly that at this age and with these other problems, monitoring may be the kinder path.
If that is where you are, you are entitled to a straight account of what you are choosing rather than a warning. This is what the disease does when it is not treated, what that usually looks like over time, and what still helps.
Why Owners Make This Choice
The reasons repeat. The dog is elderly and something else — kidney disease, cardiac disease, a cancer diagnosis — is already the shorter clock. The cost of lifelong medication and quarterly monitoring is genuinely out of reach. The dog is difficult to medicate and the twice-daily routine becomes a twice-daily fight. Or the signs are mild, the dog seems comfortable, and the veterinarian has suggested watching rather than starting treatment right away.
That last one is worth separating out, because it is not the same decision. Monitoring a mildly affected dog under veterinary supervision, with a plan to start treatment when the picture changes, is a treatment strategy. Declining treatment altogether is a different path, and both are legitimate — but only one of them involves a scheduled next appointment.
What the Disease Does Without Treatment
Untreated, cortisol stays high, and the effects accumulate gradually rather than arriving as a crisis. The visible signs generally intensify: thirst and urination increase, accidents in the house become more frequent, the abdomen distends as abdominal muscle weakens, the coat thins and regrows poorly, and the panting becomes a feature of the nights.
Beneath those, the consequences that matter clinically are the ones you cannot see. Muscle loss progresses, and hind-end weakness follows it. Skin becomes thin and fragile and heals slowly. Urinary tract infections are frequent and often silent. Blood pressure runs high in most affected dogs, and protein is lost through the kidneys. Some dogs develop diabetes, which is a second disease with its own demands. The risk of a clotting event is elevated. Calcinosis cutis — firm mineral deposits in the skin — is uncomfortable and difficult to manage.
The honest limitation on all of this: most of what veterinary medicine knows about survival in Cushing’s comes from studies of treated dogs, because treated dogs are the ones being followed. Nobody can give you a reliable number for how long an untreated dog lives, and anyone who offers one with confidence is going beyond the evidence.
It Is Usually Slow, and That Changes the Decision
Cushing’s is not typically a fast disease. Many dogs live a considerable time with it, treated or not, and for a dog who is already elderly the arithmetic that matters is often about comfort over the coming months rather than years gained.
This cuts both ways, and it is worth sitting with both edges. A slow disease means a decision not to treat does not mean losing your dog soon. It also means the daily burdens — the accidents, the restless nights, the weakness — are things you and your dog may be living with for a long stretch. Which of those weighs more depends on your dog and your situation, and it is not a question with a general answer.
What Still Helps When You Are Not Treating the Cortisol
• Never restrict water. The thirst is the body compensating for water it is losing. Taking the bowl away does not reduce the urination; it risks dehydration. Add bowls rather than removing them.
• Make the accidents easier. More frequent trips outside, washable bedding, waterproof covers, pads near the door. Accidents in a Cushing’s dog are a physical consequence, not a training failure, and treating them as one spares you both.
• Watch for infections. Because the immune response is suppressed, a urinary tract infection may show no straining and no discomfort at all. A urine sample checked periodically catches what symptoms will not, and infections are treatable regardless of what you decide about the Cushing’s itself.
• Protect the skin. Thin skin tears easily. Gentle handling, soft harnesses rather than collars that drag, and prompt attention to any wound that is not closing.
• Adapt the house for a weaker dog. Non-slip runners on hard floors, ramps instead of stairs and jumps, a bed that is easy to get out of.
• Keep the veterinary relationship open. Declining treatment is not the same as declining care. Blood pressure, infections, pain, and the secondary problems are all still worth addressing, and your vet can help with all of them.
Questions Worth Asking Your Veterinarian
Ask what they expect the next six months to look like for your dog specifically, given the other conditions in the picture. Ask which quality-of-life assessment they use, and go through it with them rather than alone at two in the morning. Ask which changes should bring you back in. And ask whether there is a smaller version of treatment worth considering — a lower-cost monitoring schedule, or addressing one complication such as blood pressure, without committing to the full protocol.
You are also allowed to change your mind. Owners who decline treatment at diagnosis sometimes start it later when circumstances shift, and that door does not close behind you.
The Bottom Line
Untreated Cushing’s progresses gradually, and the load falls on the skin, the muscles, the kidneys, the blood pressure, and the infection risk. The visible signs get harder to live with, and the invisible ones get quietly worse. But choosing not to treat the cortisol is not choosing to do nothing — water, infection checks, skin care, a safer floor, and honest quality-of-life conversations with your veterinarian all remain available, and all of them matter. If you are weighing this, the most useful next step is a conversation with your vet about your dog, not a decision made from a page about dogs in general. What the later stages of this disease look like is covered separately, if that is what you are trying to prepare for.
Sources
• Merck Veterinary Manual — Cushing Disease (Pituitary-Dependent Hyperadrenocorticism) in Animals. https://www.merckvetmanual.com/endocrine-system/the-pituitary-gland/cushing-disease-pituitary-dependent-hyperadrenocorticism-in-animals
• Merck Veterinary Manual — Disorders of the Adrenal Glands in Dogs. https://www.merckvetmanual.com/dog-owners/hormonal-disorders-of-dogs/disorders-of-the-adrenal-glands-in-dogs
• Merck Veterinary Manual — Pulmonary Thromboembolism in Dogs. https://www.merckvetmanual.com/dog-owners/lung-and-airway-disorders-of-dogs/pulmonary-thromboembolism-in-dogs
