Tests, Costs & What to Expect
Learn how to diagnose Cushing's disease in dogs — from early symptoms and vet tests (LDDST, ACTH) to treatment costs, prognosis, and breed risk factors.
What Is Cushing's Disease in Dogs?
Cushing's disease, medically known as hyperadrenocorticism (HAC), occurs when a dog's body produces excessive levels of cortisol — the primary stress hormone. In roughly 80–85% of cases, the cause is a benign pituitary tumor (pituitary-dependent hyperadrenocorticism, or PDH) that overstimulates the adrenal glands. The remaining 15–20% stem from adrenal tumors (adrenal-dependent hyperadrenocorticism, or ADH) that secrete cortisol directly. A third form, iatrogenic Cushing's, develops from prolonged use of corticosteroid medications like prednisone.
The condition is relatively common in middle-aged and older dogs. According to the Merck Veterinary Manual, Cushing's disease is one of the most frequently diagnosed endocrine disorders in canine practice. Understanding how to diagnose Cushing's disease in dogs requires patience — the testing process is multi-step, and no single test is perfect. Misdiagnosis is common when owners and even clinicians rely on symptoms alone, which is why a structured diagnostic protocol is essential.
Important: This guide is for educational purposes. Always consult your veterinarian for diagnosis and treatment decisions. Do not attempt to diagnose or treat Cushing's disease at home.
Early Warning Signs vs. Advanced Symptoms of Cushing's Disease
Cushing's disease develops gradually, often over months or even years. Early symptoms are easy to dismiss as normal aging. By the time advanced signs appear, the disease is well-established. Use this checklist to track what you're observing at home before your vet visit.
| Severity | Symptom | What You'll Notice |
|---|---|---|
| Early / Mild | Increased thirst (polydipsia) | Drinking noticeably more water; bowl empties faster than usual |
| Increased urination (polyuria) | More frequent potty breaks; accidents in a previously house-trained dog | |
| Increased appetite (polyphagia) | Begging more, stealing food, seeming constantly hungry | |
| Mild panting | Panting more than usual at rest or in cool environments | |
| Slightly pot-bellied appearance | Abdomen looks rounder; subtle weight gain around the midsection | |
| Moderate / Progressive | Pronounced abdominal distension | "Pot belly" becomes obvious; trunk looks swollen while legs appear thin |
| Bilateral hair loss (alopecia) | Symmetric thinning on flanks, abdomen, and thighs — head and legs typically spared | |
| Thin, fragile skin | Skin tears easily; slow wound healing; visible blood vessels | |
| Muscle wasting | Noticeable thinning of leg and temple muscles; weakness on stairs | |
| Recurring skin infections | Hot spots, bacterial or yeast infections that keep returning after treatment | |
| Calcium deposits in skin (calcinosis cutis) | Hard, gritty patches on the back, neck, or groin | |
| Darkened skin (hyperpigmentation) | Patches of skin turning dark gray or black, especially on the abdomen | |
| Advanced / Severe | Neurological signs | Disorientation, head pressing, seizures, pacing — suggests large pituitary macroadenoma |
| Diabetes mellitus (comorbidity) | Secondary diabetes develops in ~10% of untreated Cushing's cases | |
| Recurrent urinary tract infections | Frequent UTIs due to immune suppression from excess cortisol | |
| Hypertension | High blood pressure; may cause retinal changes or kidney damage | |
| Pulmonary thromboembolism | Blood clots in the lungs; sudden breathing difficulty — life-threatening emergency |
Contact your veterinarian or an emergency clinic right away if your dog shows any of these red-flag symptoms:
- Sudden collapse or inability to stand
- Severe disorientation, head pressing, or seizures
- Rapid, labored breathing or gasping
- Sudden blindness or dramatic vision changes
- Vomiting or diarrhea that won't stop (especially if on trilostane)
- Extreme lethargy or unresponsiveness
Neurological signs may indicate a pituitary macroadenoma (tumor >1 cm) pressing on the brain. Breathing difficulty could signal a pulmonary thromboembolism — both require emergency intervention.
Which Dogs Are Most at Risk? Breed, Age, and Genetic Factors
Cushing's disease doesn't affect all dogs equally. Knowing your dog's risk profile helps you and your vet stay alert to early signs.
Breed Predisposition (Pituitary-Dependent Cushing's):
- Poodles (Miniature and Standard)
- Dachshunds
- Small Terriers: Yorkshire Terriers, Boston Terriers, Jack Russell Terriers
- Beagles
- Cocker Spaniels
Breed Predisposition (Adrenal Tumors — larger breeds more common):
- German Shepherds
- Labrador Retrievers
- Australian Shepherds
Age: Most dogs are diagnosed between 7 and 12 years old. PDH can occasionally appear in dogs as young as 5–6, but this is uncommon.
Sex: Females are slightly more likely to develop PDH. Adrenal tumors show a stronger female predisposition — roughly 60% of ADH cases occur in females.
Weight: Overweight dogs aren't necessarily more likely to develop Cushing's, but excess weight can mask the early pot-bellied appearance, delaying recognition.
Medication History: Dogs on long-term corticosteroids (prednisone, dexamethasone) for allergies, autoimmune disease, or other conditions are at risk for iatrogenic Cushing's. This form is reversible by tapering the medication under veterinary supervision.
How to Diagnose Cushing's Disease in Dogs: The Veterinary Testing Protocol
Diagnosing Cushing's disease is a multi-step process. No single test provides a definitive answer on its own, which is why your vet will follow a structured protocol. Here's what to expect at each stage.
Step 1: Screening Blood Work and Urinalysis
Your vet will start with a complete blood count (CBC), serum biochemistry panel, and urinalysis. These don't diagnose Cushing's directly, but they reveal characteristic patterns:
- Elevated alkaline phosphatase (ALP): Present in ~85–90% of Cushing's dogs. This is often the first clue on routine blood work.
- Elevated ALT (alanine aminotransferase): Mild-to-moderate elevation in ~50% of cases.
- Stress leukogram: Elevated neutrophils, decreased lymphocytes and eosinophils — seen in ~60% of cases.
- Hypercholesterolemia and hyperglycemia: Present in many but not all cases.
- Urine specific gravity: Often low (dilute urine) due to excessive drinking.
- Proteinuria: Protein in the urine, indicating kidney stress.
If these results are consistent with Cushing's and your dog has compatible symptoms, your vet moves to confirmatory testing.
Step 2: Confirmatory Hormone Tests
Two primary tests confirm Cushing's disease. Your vet may run one or both, depending on clinical suspicion.
| Test | How It Works | Accuracy | Typical Cost |
|---|---|---|---|
| Low-Dose Dexamethasone Suppression Test (LDDST) | Blood is drawn, then a small dose of dexamethasone (a synthetic steroid) is injected. Blood is re-drawn at 4 hours and 8 hours. In healthy dogs, dexamethasone suppresses cortisol production. In Cushing's dogs, cortisol remains elevated at 8 hours. | ~90–95% sensitivity for PDH; slightly lower for ADH | $200–$350 |
| ACTH Stimulation Test | Blood is drawn, then synthetic ACTH hormone is injected to stimulate the adrenal glands. Blood is re-drawn after 1 hour. Cushing's dogs show an exaggerated cortisol response. | ~80% sensitivity for PDH; ~60% for ADH. Better for confirming iatrogenic Cushing's and monitoring treatment. | $150–$300 |
| Urine Cortisol:Creatinine Ratio (UCCR) | Owner collects a morning urine sample at home (less stressful). High ratios suggest Cushing's, but the test has low specificity — stress, illness, and other conditions can elevate results. | High sensitivity (~95%) but low specificity (~20–25%). Best used as a rule-out test: a normal result makes Cushing's very unlikely. | $50–$100 |
The American Kennel Club notes that the LDDST is generally considered the gold-standard screening test for naturally occurring Cushing's disease, while the ACTH stimulation test is preferred for monitoring treatment response once medication begins.
Step 3: Differentiating PDH from ADH
Once Cushing's is confirmed, your vet needs to determine whether it's pituitary-dependent or adrenal-dependent — because the treatment paths differ significantly.
- High-Dose Dexamethasone Suppression Test (HDDST): Similar to the LDDST but uses a higher steroid dose. In PDH, the pituitary partially responds and cortisol drops. In ADH, there's no suppression. Accuracy is moderate — about 70–75% for differentiation.
- Endogenous ACTH Level: A specialized blood test measuring the dog's own ACTH. High levels suggest PDH; low levels suggest ADH. Results can be variable. Cost: $150–$250.
- Abdominal Ultrasound: The most practical differentiating tool. If one adrenal gland is enlarged and the other is atrophied (shrunken), it points to an adrenal tumor. If both are symmetrically enlarged, it suggests PDH. Cost: $300–$600.
- CT or MRI of the Brain: Recommended if neurological symptoms are present or if surgery is being considered. Visualizes pituitary tumors directly. Cost: $1,500–$3,500 depending on facility.
Can Cushing's Disease Be Treated? Medical and Surgical Options
Cushing's disease is treatable in most cases, but "treatable" doesn't always mean "curable." The approach depends on whether the cause is PDH, ADH, or iatrogenic.
| Treatment | Type | How It Works | Success Rate / Notes | Estimated Monthly Cost |
|---|---|---|---|---|
| Trilostane (Vetoryl®) | Medical (first-line for PDH) | Inhibits cortisol production in the adrenal glands. Given daily with food. Requires regular ACTH stimulation monitoring. | Clinical improvement in 80–90% of dogs within 2–4 weeks. Does not cure PDH — manages it lifelong. | $40–$120/month depending on dog size (30 mg–120 mg capsules) |
| Mitotane (Lysodren®) | Medical (older alternative) | Selectively destroys the cortisol-producing layer of the adrenal cortex. Given in an induction phase then maintenance. | Effective in 70–85% of cases. Higher risk of side effects (Addisonian crisis) than trilostane. Less commonly used as first-line since Vetoryl's FDA approval. | $30–$80/month |
| Adrenalectomy | Surgical (for ADH) | Removal of the affected adrenal gland. Performed by a board-certified veterinary surgeon. | If the tumor is benign and hasn't invaded blood vessels, surgery can be curative. Perioperative mortality is ~5–10% in experienced hands. Malignant adrenal tumors have a poorer prognosis. | $3,000–$7,000 one-time (surgery + hospitalization) |
| Pituitary Radiation (Stereotactic Radiosurgery) | Specialized (for pituitary macroadenomas) | Targeted radiation to shrink the pituitary tumor. Available at select veterinary teaching hospitals and specialty centers. | Can reduce tumor size and improve neurological signs over months. Not widely available. Often combined with trilostane. | $4,000–$8,000 one-time |
| Gradual Steroid Taper | Supportive (iatrogenic Cushing's) | Slowly reducing the dose of the causative corticosteroid under veterinary guidance. | Fully reversible if the underlying condition allows steroid discontinuation. Adrenal function typically recovers over weeks to months. | Minimal (vet monitoring visits) |
Monitoring during treatment: Dogs on trilostane or mitotane require ACTH stimulation tests at 10–14 days, 30 days, 90 days, and then every 3–6 months for life. Each monitoring visit with blood work typically costs $150–$300. Skipping monitoring is dangerous — overtreatment can cause an Addisonian crisis (hypoadrenocorticism), which is life-threatening.
Prognosis and Life Expectancy by Disease Type and Stage
Prognosis varies considerably depending on the underlying cause, tumor behavior, and how early the disease is caught. Here's a realistic breakdown based on published veterinary literature.
| Condition | Median Survival Time (Treated) | Key Prognostic Factors |
|---|---|---|
| PDH — managed medically (trilostane or mitotane) | 2–2.5 years from diagnosis (many dogs live 3–5+ years with good monitoring) | Excellent quality of life for most. Prognosis worsens if diabetes, recurrent infections, or hypertension develop as comorbidities. |
| PDH with pituitary macroadenoma (>1 cm) | 6–12 months without radiation; longer with radiation therapy | Neurological signs at diagnosis worsen prognosis. Approximately 10–15% of PDH dogs develop macroadenomas over time. |
| ADH — benign adrenal tumor, surgically removed | Potentially curative; normal life expectancy if surgery is successful | Best outcome of all Cushing's subtypes. The remaining adrenal gland usually recovers function within weeks to months. |
| ADH — malignant adrenal tumor | 6–18 months with surgery; shorter if metastasis has occurred | Approximately 50% of adrenal tumors are malignant (adenocarcinomas). Vascular invasion significantly reduces survival. |
| Iatrogenic Cushing's | Full recovery expected if steroids can be safely tapered | Depends on the underlying condition requiring steroids. Adrenal recovery may take 2–6 months. |
| Untreated Cushing's (any type) | Median ~1 year, with declining quality of life | Risk of fatal complications: pulmonary thromboembolism, severe infections, diabetic ketoacidosis, kidney failure. |
It's worth noting that many dogs with well-managed PDH die of unrelated causes (cancer, heart disease, old age) rather than from Cushing's itself. Early diagnosis and consistent monitoring are the strongest predictors of a good outcome.
Home Care and Daily Management for Dogs with Cushing's Disease
Once your dog is diagnosed and treatment begins, your daily management routine becomes critical to long-term success. Here's what life looks like as a Cushing's dog parent.
Daily Medication Administration
Trilostane (Vetoryl) should be given once daily with food — ideally at the same time each morning. Consistency matters because cortisol levels fluctuate, and your vet will schedule monitoring tests relative to the dosing time. Use a pill organizer or phone alarm to avoid missed doses. If you miss a dose, give it when you remember unless it's close to the next dose — never double up.
Monitoring Water Intake and Urination
Track your dog's daily water consumption during the first few months of treatment. A reduction in drinking and urination is one of the first signs that medication is working. Measure water in a marked bowl or use a measured pitcher. Typical water intake for a healthy dog is approximately 50–60 mL per kg of body weight per day — if your dog was drinking 100+ mL/kg/day before treatment, you should see this decrease within 2–4 weeks of effective trilostane therapy.
Diet and Weight Management
Most dogs with Cushing's benefit from a moderate-protein, moderate-fat diet with controlled sodium. If your dog has concurrent kidney issues or hypertension, your vet may recommend a prescription renal or cardiac diet. Avoid high-sodium treats. Monitor body condition score (BCS) monthly — aim for a BCS of 4–5 out of 9.
Skin and Coat Care
Hair regrowth is slow — expect 3–6 months for noticeable improvement after cortisol levels normalize. Medicated shampoos (chlorhexidine-based) can help manage recurring skin infections. Keep your dog's skin moisturized with veterinary-approved sprays if it becomes excessively dry or flaky. Watch for calcinosis cutis lesions, which may take months to resolve.
Recognizing an Addisonian Crisis
Overtreatment with trilostane or mitotane can push cortisol levels too low, causing hypoadrenocorticism (Addison's disease). Signs include sudden vomiting, diarrhea, weakness, collapse, and loss of appetite. This is a medical emergency — contact your vet immediately. Your vet may instruct you to stop the medication and bring your dog in for IV fluids and dexamethasone.
How Much Does Cushing's Disease Diagnosis and Treatment Cost?
Budgeting for Cushing's disease requires understanding both upfront diagnostic costs and ongoing management expenses. Here's a realistic breakdown based on typical US veterinary pricing in 2025–2026.
| Expense Category | Low Estimate | High Estimate | Frequency |
|---|---|---|---|
| Initial blood work (CBC, chemistry, urinalysis) | $150 | $300 | One-time |
| LDDST confirmatory test | $200 | $350 | One-time (may repeat if inconclusive) |
| ACTH stimulation test | $150 | $300 | Initial + every 3–6 months |
| Abdominal ultrasound | $300 | $600 | One-time (may repeat annually) |
| CT or MRI (brain) | $1,500 | $3,500 | One-time if indicated |
| Trilostane (Vetoryl) medication | $40/month | $120/month | Lifelong |
| Monitoring vet visits with ACTH stim | $150 | $300 | Every 3–6 months |
| Adrenalectomy surgery (ADH) | $3,000 | $7,000 | One-time if applicable |
| Emergency visit (Addisonian crisis) | $500 | $2,000 | As needed |
First-year total (PDH, medical management): Expect to spend approximately $1,500–$3,500 in the first year, including diagnosis, medication, and initial monitoring visits.
Ongoing annual cost: Approximately $800–$2,000 per year for medication and monitoring.
Worst-case scenario: If your dog requires brain imaging, radiation therapy, or multiple emergency visits, first-year costs can exceed $8,000–$12,000.
Pet insurance can help, but most policies exclude pre-existing conditions. If your dog is young and healthy now, enrolling in a comprehensive plan before any Cushing's symptoms appear is the most financially protective strategy. Check whether your policy covers endocrine disorders — most comprehensive plans from providers like Trupanion, Healthy Paws, and Nationwide do cover Cushing's if it's not pre-existing.
Frequently Asked Questions
Can Cushing's disease in dogs be prevented?
For naturally occurring Cushing's (PDH and ADH), there is no known prevention strategy — these are caused by tumors that develop spontaneously. The only preventable form is iatrogenic Cushing's, which can be avoided by using corticosteroid medications only when medically necessary and at the lowest effective dose for the shortest duration. If your dog requires long-term steroids for allergies or autoimmune disease, discuss steroid-sparing alternatives with your vet, such as oclacitinib (Apoquel®) for allergic dermatitis or cyclosporine (Atopica®) for immune-mediated conditions.
How is Cushing's disease diagnosed if the first test is inconclusive?
Diagnosing Cushing's disease in dogs can be frustrating because early-stage or mild cases sometimes produce borderline results. If the LDDST is equivocal, your vet may repeat the test in 4–8 weeks, add an ACTH stimulation test, or use the urine cortisol:creatinine ratio as supplementary evidence. In some cases, clinical signs are so classic that a vet will begin a therapeutic trial of trilostane and monitor for improvement — though this approach is controversial and should only be done under close veterinary supervision.
Is Cushing's disease painful for dogs?
Cushing's itself is not typically painful, but its secondary effects can cause significant discomfort. Recurring skin infections are itchy and irritating. Muscle wasting makes movement difficult. Calcinosis cutis lesions can be tender. Large pituitary tumors may cause headaches (manifesting as head pressing or behavioral changes). Most owners report that their dog's energy, comfort, and happiness improve noticeably within weeks of starting treatment.
Can I give my dog natural or herbal remedies for Cushing's disease?
There is no scientifically validated natural cure for Cushing's disease. Some supplements — such as melatonin, lignans (from flaxseed), and phosphatidylserine — have been explored in small studies or anecdotal reports for mild cases or as adjuncts. However, none of these replace the proven efficacy of trilostane or mitotane. Discuss any supplements with your veterinarian before starting them, as some can interact with prescribed medications or affect liver function tests.
Will my dog's hair grow back after Cushing's treatment?
In most cases, yes — but slowly. Hair regrowth typically begins 2–4 months after cortisol levels normalize and can take 6–12 months for full coat recovery. Some dogs, particularly those with long-standing disease, may have permanent thinning in certain areas. Calcinosis cutis lesions may leave scars. Regular grooming and skin care support the regrowth process.
How often does my dog need vet visits after diagnosis?
After starting trilostane or mitotane, expect vet visits at approximately 10–14 days, 30 days, 60 days, and 90 days for ACTH stimulation tests and dose adjustments. Once your dog is stable, visits typically reduce to every 3–6 months for the rest of your dog's life. Missing these monitoring appointments is risky — both undertreatment and overtreatment carry serious health consequences.
Key Takeaways for Dog Owners
If your dog is drinking excessively, urinating more frequently, losing hair symmetrically, and developing a pot-bellied appearance — especially if they're a middle-aged Poodle, Dachshund, or small terrier — Cushing's disease should be on your radar. The diagnostic process involves multiple steps and can take 1–3 vet visits to complete, but the testing protocol is well-established and widely available.
Treatment with trilostane (Vetoryl) is effective for the majority of dogs with pituitary-dependent Cushing's, and surgical removal of benign adrenal tumors can be curative. Consistent monitoring, daily medication adherence, and a watchful eye for complications are the keys to giving your dog a comfortable life with this manageable — though lifelong — endocrine condition.
Sources consulted: Merck Veterinary Manual — Hyperadrenocorticism in Dogs, AKC — Cushing's Disease in Dogs, and peer-reviewed literature from the Journal of Veterinary Internal Medicine.
Tom Renshaw
All our authors care for dogs every day — read more of their work on the authors page.
