Cushing's Disease in Dogs: Diet and Nutrition Guide

By Dr. Zubair Khalid, DVM, MS, PhD · 2026-10-02

This article is educational and is not a substitute for veterinary diagnosis or treatment.

If you are searching for the right dog food for Cushing's disease, the honest answer is that no single diet treats the disease. Nutrition matters a great deal for how your dog feels day to day, but the excess cortisol driving Cushing's must be managed with veterinary treatment. Food works alongside that treatment, not instead of it.

Quick Answer

• Cushing's disease is caused by a pituitary tumor that drives excess cortisol production in most dogs, and diet cannot lower that cortisol [1][2].
• Most dogs with Cushing's do best on a complete, balanced diet with high-quality protein to help counter muscle loss [2].
• Weight management matters because a pendulous abdomen and muscle wasting are common, and extra body fat adds strain [2].
• A homemade dog diet for Cushing's disease can work, but only when a veterinary nutritionist formulates it to be complete and balanced.
• Never restrict protein or calories on your own, and never stop or change Cushing's medication based on diet alone.

What Is Cushing's Disease in Dogs?

Cushing's disease is a hormonal disorder. The pituitary gland at the base of the brain develops a small tumor that pumps out too much ACTH, a hormone that tells the adrenal glands to make cortisol [1]. The adrenal glands then release cortisol far above normal levels, day after day.

Cortisol is the body's stress hormone. In normal amounts it helps regulate blood sugar, blood pressure, and inflammation. In constant excess, it reshapes the body and wears down organs and muscle. The term "Cushing syndrome" is the umbrella label for any condition with too much cortisol, while "Cushing disease" refers specifically to the pituitary form [1][2]. Pituitary-dependent disease accounts for 80% to 85% of reported cases, making it the most common type by far [2].

You may also hear about adrenal-dependent Cushing's, where a tumor on the adrenal gland itself secretes cortisol. That form is less common, at roughly 10% to 15% of cases [3]. The distinction changes treatment, so it is worth understanding. You can read more in this guide to pituitary vs adrenal hyperadrenocorticism.

Signs Owners Notice First

Cushing's tends to creep in slowly, and owners often blame aging at first. The classic signs include:

• Drinking much more water and urinating far more often (polyuria and polydipsia) [1][2]
• A ravenous appetite, sometimes with food guarding or begging [2]
• A pot-bellied, pendulous abdomen
• Panting more than usual
• Muscle wasting, especially over the back and hind legs [2]
• Hair loss, thinning coat, and skin changes [1][2]
• Weakness, trouble rising, or reluctance to climb stairs

Some of these signs overlap with other conditions, which is one reason diagnosis takes more than a single test. Behavior changes such as irritability, restlessness, or anxiety are also common and are covered in this article on Cushing disease dog behavior problems.

Causes and Risk Factors

The root cause in most dogs is a benign pituitary tumor that overproduces ACTH [1]. Adrenal tumors cause a smaller share of cases [3]. Long-term use of corticosteroid drugs, such as prednisone for allergies or immune disease, can also produce the same signs, and this form is managed differently [3].

Cushing's is a disease of adult and older dogs [3]. Certain breeds appear more often in veterinary practice, though published research do not list specific breed percentages, so treat breed predisposition as general veterinary knowledge instead of a fixed number. If your dog is middle-aged or older and showing the signs above, testing is reasonable.

How Cushing's Disease Is Diagnosed

Diagnosis is a process, not a single blood test. Your veterinarian will start with history and physical exam, then move to laboratory work.

Newer screening tools are being studied. A machine learning model using routine blood work and urinalysis reached about 88.5% accuracy in one study, which suggests these everyday tests carry more diagnostic signal than once thought [4]. This is not yet standard practice, but it points to how screening may improve.

Because the tests can be affected by other illness and by stress, your veterinarian may repeat or combine them. If your dog has other conditions, tell your vet, since that changes how results are read.

Treatment Options for Cushing's Disease

Treatment depends on which form your dog has and how sick they are.

For pituitary-dependent Cushing's, medical management is the mainstay. Trilostane and mitotane are the two drugs most studied for survival, and a meta-analysis found no statistically significant difference in survival time between them [5]. In practice, trilostane is widely used. Among primary care veterinarians surveyed in several European countries, 87.6% used trilostane, given either once or twice daily [6]. Your veterinarian calculates the dose from your dog's weight, test results, and overall health, then adjusts it over time.

Surgery is an option in some cases. Adrenalectomy can cure adrenal-dependent disease, and a review found no significant survival difference between laparoscopic and open adrenalectomy at 12, 24, or 36 months [7]. For pituitary tumors, radiotherapy improved survival at 12 months with fractionated protocols and at 24 months with both fractionated and stereotactic protocols, though the benefit was not maintained at 36 months [7]. Radiotherapy also improved neurologic outcomes [7].

Diet does not replace any of these. It supports the body while treatment does the work of lowering cortisol.

Diet and Nutrition: What to Feed a Dog with Cushing's

This is the part owners ask about most, and it deserves a careful answer.

Protein Needs

Cushing's causes muscle wasting, so adequate protein is a priority [2]. Muscle loss is not just cosmetic. It affects strength, mobility, and quality of life. A diet with high-quality, highly digestible protein helps your dog hold onto lean muscle while cortisol is being controlled.

Do not put your dog on a low-protein diet unless your veterinarian specifically recommends it for kidney or liver disease. Restricting protein in a dog already losing muscle can make things worse. The right protein level depends on your dog's body condition, kidney function, and other health issues, so let your veterinarian set the target.

Weight Management

Many dogs with Cushing's carry extra weight or develop a pot-bellied appearance from fat redistribution and abdominal muscle weakness [2]. Keeping your dog at a healthy body condition score reduces strain on joints and the heart. Your veterinarian can score body condition at each visit and give you a target weight.

Weigh your dog at home if you can, or use clinic scales monthly. Small, consistent changes beat drastic dieting. Sudden severe calorie restriction is not appropriate for a dog with a chronic illness unless your vet directs it.

Homemade Diets

A homemade dog diet for Cushing's disease can be a good option, but it must be complete and balanced. Home-cooked meals made from guesswork are a common source of nutrient deficiencies, especially in calcium, zinc, and certain vitamins. Ask your veterinarian for a referral to a board-certified veterinary nutritionist, or use a veterinary-formulated recipe designed for your dog's exact needs.

If you want to cook for your dog, do it with a recipe, not by instinct. A nutritionist will account for your dog's weight, protein needs, and any organ conditions. For general guidance on choosing commercial diets, see dog food and diet dog food.

Practical Feeding Tips

• Feed measured meals at set times instead of free-feeding, especially if your dog has a ravenous appetite [2].
• Use a portion of the daily kibble as training rewards to avoid extra calories.
• Keep treats under about 10% of daily calories, a standard feeding guideline.
• Transition foods over 7 to 10 days to avoid stomach upset.
• Fresh water must always be available, since increased urination means increased fluid loss [1].

What About Supplements?

Owners often ask about herbs, glandular supplements, or "adrenal support" products. There is no well-established evidence that these lower cortisol in dogs, and some can interfere with medication or lab tests. Tell your veterinarian about everything your dog takes, including over-the-counter products.

Recovery, Outlook, and Long-Term Management

Cushing's is usually managed, not cured, in its pituitary form. With treatment, many dogs improve in thirst, urination, appetite, and energy over weeks to months. Your veterinarian will recheck blood work and adjust medication, often starting with a follow-up visit within a few weeks of beginning treatment [6].

Long-term care means regular monitoring. Expect periodic blood tests to check cortisol control and organ values. Watch for signs that medication is too high or too low, such as lethargy, vomiting, or a return of heavy drinking. Report changes promptly.

Some dogs develop protein in the urine from kidney effects of cortisol. In one study, 13 of 19 dogs with Cushing's had glomerular proteinuria, and severity decreased during trilostane treatment [8]. This is another reason routine urine testing matters.

Rarely, severe cases can involve bone problems. A case report described a dog with multiple pathological bone fractures and low bone density [9]. This is uncommon, but it shows why weakness or new pain in a Cushing's dog deserves a veterinary exam.

For a broader view of daily care, see what to expect from diagnosis to daily management.

Prevention

You cannot prevent the pituitary or adrenal tumors that cause most Cushing's cases. What you can do is reduce one known trigger: long-term corticosteroid use. If your dog takes steroids for another condition, ask your veterinarian about the lowest effective dose and whether alternatives exist [3].

Beyond that, prevention focuses on early detection. Annual or twice-yearly wellness visits for older dogs, with blood work and urinalysis, help catch changes early. Keep your dog lean, since obesity worsens many chronic conditions. Report new thirst, urination, or appetite changes right away instead of waiting for the next scheduled visit.

Limitations and When to Contact a Veterinarian

Diet is supportive care. It cannot control cortisol, and no food or supplement replaces veterinary treatment. Every dog's case is different, so your veterinarian needs to guide the plan for your individual pet.

Contact your veterinarian the same day if you notice:

• Vomiting, diarrhea, or refusal to eat
• Sudden weakness, collapse, or trouble standing
• Marked lethargy or confusion
• A return of heavy drinking and urination after starting treatment

Seek emergency care now if your dog has a seizure, severe difficulty breathing, or cannot rise.

Call for a routine visit if you see gradual increases in thirst, urination, or appetite, new hair loss, or a changing body shape. Early adjustments to treatment are easier than crisis management.

Frequently Asked Questions

Can I treat my dog's Cushing's with diet alone?

No. Diet supports your dog but does not lower the excess cortisol that causes the disease. Treatment with medication, surgery, or radiation is what controls the hormone problem, and your veterinarian decides which approach fits your dog.

What should I look for in a dog food for Cushing's disease?

Look for a complete and balanced diet with high-quality protein and a calorie level that keeps your dog at a healthy weight. Your veterinarian can recommend a specific protein and fat target based on your dog's body condition and any organ conditions.

Is a homemade diet better than commercial food for a dog with Cushing's?

Not automatically. A homemade diet is only better if it is complete and balanced, which usually requires a recipe from a veterinary nutritionist. Improvised home cooking often falls short on key nutrients and can do more harm than good.

Should I limit protein for my dog with Cushing's?

Usually not. Muscle wasting is a hallmark of the disease, so adequate protein helps preserve muscle. Only restrict protein if your veterinarian finds a specific reason, such as advanced kidney disease.

How often will my dog need checkups after starting treatment?

Your veterinarian sets the schedule, and it often starts with a follow-up visit within a few weeks of beginning medication. After that, monitoring continues at intervals your vet chooses based on how well your dog is doing and what the blood work shows.

Related Articles

• Cushings Disease in Dogs: Pituitary vs Adrenal Hyperadrenocorticism Guide
• Cushing Disease Dog Behavior Problems
• Diet Dog Food
• Dog Cushing's Disease: What to Expect from Diagnosis to Daily Management
• Dog Food
• Healthy Diet For Dogs

References

1. Cushing Disease (Pituitary-Dependent Hyperadrenocorticism) in Animals - Endocrine System. Merck Veterinary Manual.
2. Cushing Syndrome (Hyperadrenocorticism) in Animals - Endocrine System. Merck Veterinary Manual.
3. Disorders of the Adrenal Glands in Dogs - Dog Owners. Merck Veterinary Manual.
4. Machine learning-assisted screening for canine Cushing's syndrome. The veterinary quarterly, 2026.
5. Effectiveness of Medical Treatment on Survivability in Canine Cushing's Syndrome: A Systematic Review and Meta-Analysis. Animals : an open access journal from MDPI, 2025.
6. Treatment and monitoring of naturally occurring Cushing's syndrome by primary care veterinarians in selected European countries. Journal of veterinary internal medicine, 2026.
7. Effectiveness of Non-Medical Treatment on Survival, Perioperative, and Clinical Outcomes in Canine Cushing's Syndrome: A Systematic Review and Network Meta-Analysis. Veterinary sciences, 2026.
8. Electrophoretic patterns of proteinuria in dogs with Cushing's syndrome. The Journal of small animal practice, 2026.
9. Multiple pathological bone fractures in a dog with adrenal-dependent Cushing's syndrome. The Journal of small animal practice, 2025.

Further Reading

• Merck Veterinary Manual: Dog Owners
• Cornell Richard P. Riney Canine Health Center: Canine Health Information
• American Veterinary Medical Association: Pet Care