Symptoms, Diagnosis, Treatment & Prognosis Guide
Complete guide to Cushing's disease in dogs: early symptoms, diagnostic tests, treatment options, costs, prognosis, and breed predispositions.
What Is Cushing's Disease in Dogs?
Cushing's disease — clinically known as hyperadrenocorticism — occurs when a dog's body produces excessive levels of cortisol, the hormone responsible for managing stress, metabolism, and immune response. The condition is relatively common in middle-aged to older dogs, with the Merck Veterinary Manual estimating that approximately 1 to 2 out of every 1,000 dogs are diagnosed annually.
There are three forms of the disease:
- Pituitary-dependent hyperadrenocorticism (PDH): Accounts for roughly 80–85% of cases. A benign tumor on the pituitary gland overproduces ACTH (adrenocorticotropic hormone), which signals the adrenal glands to release excess cortisol.
- Adrenal-dependent hyperadrenocorticism (ADH): Makes up about 15–20% of cases. A tumor (benign or malignant) on one adrenal gland directly overproduces cortisol.
- Iatrogenic Cushing's: Caused by long-term administration of corticosteroid medications such as prednisone, dexamethasone, or methylprednisolone — often prescribed for allergies, autoimmune disease, or arthritis.
Left untreated, Cushing's disease progressively damages organs, weakens the immune system, and significantly reduces quality of life. The good news: with early detection and proper management, most dogs live comfortably for years after diagnosis.
Recognizing the Symptoms: Early Warning Signs vs. Advanced Stages
Cushing's disease is notoriously gradual in onset. Many owners dismiss early signs as "just getting old." The following checklist separates early indicators from advanced-stage symptoms so you can act before the disease progresses significantly.
| Severity | Symptom | What You'll Notice |
|---|---|---|
| Early Warning Signs | Increased thirst (polydipsia) | Water bowl empties faster; dog drinks 2–3× normal volume |
| Increased urination (polyuria) | More frequent bathroom breaks; indoor accidents in house-trained dogs | |
| Increased appetite (polyphagia) | Begging more, eating faster, scavenging, stealing food | |
| Mild panting | Panting at rest or in cool environments without exertion | |
| Slight potbelly appearance | Abdomen looks rounder or distended despite no weight gain elsewhere | |
| Hair thinning | Coat looks duller, thinner along flanks and belly; slow regrowth after clipping | |
| Advanced Symptoms | Severe bilateral hair loss (alopecia) | Symmetric bald patches on trunk, flanks, and thighs; skin visible |
| Muscle wasting | Thin legs, visible spine/ribs despite rounded abdomen; weakness on stairs | |
| Skin changes | Dark, thickened patches (hyperpigmentation); calcium deposits (calcinosis cutis) — hard, gritty plaques | |
| Recurrent infections | Frequent UTIs, skin infections, ear infections due to immune suppression | |
| Lethargy and weakness | Reluctance to walk, play, or climb; sleeping significantly more | |
| Neurological signs (pituitary macrotumor) | Disorientation, head pressing, seizures, vision changes — occurs in ~10% of PDH cases |
Breed Predispositions and Risk Factors
While any dog can develop Cushing's disease, certain breeds carry significantly higher risk. Age and medical history also play important roles in determining susceptibility.
Key Risk Factors
- Age: Most commonly diagnosed in dogs aged 7–12 years; rare in dogs under 6
- Sex: Females are slightly more predisposed than males (approximately 60/40 ratio in PDH cases)
- Weight: Overweight dogs don't cause Cushing's, but obesity can mask early potbelly symptoms and complicate diagnosis
- Steroid history: Dogs on long-term corticosteroid therapy (oral, injectable, or topical) for allergies, ear infections, or autoimmune conditions
- Genetics: Strong hereditary component in predisposed breeds
Which Breeds Are Most Prone to Cushing's Disease?
According to the American Kennel Club, the following breeds show elevated rates of hyperadrenocorticism:
| Breed | Primary Risk Type | Notes |
|---|---|---|
| Poodle (Miniature & Standard) | PDH | Among the highest-risk breeds overall |
| Dachshund | PDH | Potbelly symptom can be confused with breed's natural body shape |
| Yorkshire Terrier | PDH | Small breeds generally at higher risk for PDH |
| German Shepherd | ADH | Higher-than-average rate of adrenal tumors |
| Boston Terrier | PDH | Brachycephalic breeds may show panting symptoms earlier |
| Beagle | PDH | Increased appetite may be harder to notice in food-motivated breeds |
| Boxer | PDH/ADH | Higher cancer predisposition increases adrenal tumor risk |
| Labrador Retriever | PDH | Weight gain may mask early symptoms |
| Australian Shepherd | PDH | Active dogs — lethargy may be more noticeable early |
| Bichon Frise | PDH | Coat changes may be first visible symptom |
How Is Cushing's Disease Diagnosed in Dogs?
Diagnosing Cushing's disease is one of the more complex processes in veterinary endocrinology. No single test provides a definitive answer — your veterinarian will use a combination of screening tests, confirmatory tests, and imaging to reach a diagnosis. Expect the process to take 1–3 visits.
Step-by-Step Diagnostic Process
- Complete Blood Count (CBC) & Chemistry Panel ($80–$200): Initial blood work often reveals elevated alkaline phosphatase (ALP), elevated cholesterol, diluted urine (low specific gravity), and sometimes elevated blood sugar. These findings raise suspicion but don't confirm Cushing's.
- Urinalysis ($40–$80): Checks for dilute urine, protein loss, glucose, and signs of concurrent UTI — common in Cushing's patients.
- Urine Cortisol:Creatinine Ratio ($50–$100): A screening test collected at home (first morning urine). A normal result effectively rules out Cushing's. An elevated result requires further testing.
- Low-Dose Dexamethasone Suppression Test (LDDST) ($150–$300): The gold-standard confirmatory test. A baseline blood sample is drawn, a small dose of dexamethasone is injected, and blood is rechecked at 4 and 8 hours. In a healthy dog, dexamethasone suppresses cortisol production. In a Cushing's dog, cortisol remains elevated. This test takes approximately 8 hours at the clinic.
- ACTH Stimulation Test ($150–$250): An alternative confirmatory test. Synthetic ACTH is injected and cortisol is measured before and 1 hour after. Less sensitive than LDDST for PDH but useful for diagnosing iatrogenic Cushing's and monitoring treatment.
- High-Dose Dexamethasone Suppression Test (HDDST) ($150–$300): If Cushing's is confirmed, this test helps differentiate PDH from ADH. Pituitary tumors partially suppress with high-dose dexamethasone; adrenal tumors do not.
- Abdominal Ultrasound ($300–$600): Visualizes the adrenal glands. In PDH, both adrenals are normal-to-enlarged. In ADH, one adrenal is enlarged (tumor) while the other is shrunken (atrophied). Also screens for liver changes and other abdominal abnormalities.
- CT or MRI ($800–$2,500): Recommended if neurological symptoms are present or if surgery is being considered for an adrenal tumor. Identifies pituitary macrotumors (>10mm) and provides surgical planning detail for adrenal masses.
Typical Diagnostic Cost Ranges (2026 Estimates)
| Test Phase | Cost Range | What's Included |
|---|---|---|
| Initial workup (blood work + urinalysis) | $120–$280 | CBC, chemistry, urinalysis |
| Confirmatory endocrine testing | $200–$600 | LDDST and/or ACTH stim test |
| Differentiation + imaging | $350–$900 | HDDST, abdominal ultrasound |
| Advanced imaging (if needed) | $800–$2,500 | CT or MRI of brain/abdomen |
| Total diagnostic cost | $670–$4,280 | Varies by case complexity |
Treatment Options: Medical, Surgical, and Supportive Care
Can Cushing's disease in dogs be cured? The answer depends on the type. Adrenal tumors can sometimes be surgically cured. Pituitary-dependent Cushing's — the most common form — is managed long-term with medication, not cured. Iatrogenic Cushing's resolves by gradually tapering the causative steroid under veterinary supervision.
| Treatment | Best For | Success Rate | Monthly Cost | Key Considerations |
|---|---|---|---|---|
| Trilostane (Vetoryl®) | PDH and ADH (first-line treatment) | 85–90% show clinical improvement within 4–6 weeks | $60–$200/month (weight-dependent) | Requires ACTH stim monitoring at 10 days, 30 days, then every 3–6 months; reversible adrenal insufficiency risk if overdosed |
| Mitotane (Lysodren®) | PDH (alternative when trilostane unavailable or ineffective) | 80–85% response rate | $40–$120/month | Selectively destroys adrenal cortex tissue; higher risk of permanent adrenal insufficiency (Addison's); loading phase then maintenance |
| Adrenalectomy (surgical removal) | ADH with benign adrenal tumor | ~90% survival with benign tumors; potential cure | $2,000–$5,000 one-time | Requires board-certified surgeon; 5–10% perioperative mortality; malignant tumors have guarded prognosis |
| Hypophysectomy (pituitary surgery) | PDH with macrotumor causing neurological signs | 70–85% short-term remission | $5,000–$10,000 one-time | Available at limited veterinary teaching hospitals; requires lifelong thyroid and cortisol supplementation post-surgery |
| Radiation therapy | Pituitary macrotumors not amenable to surgery | Variable — reduces tumor size, improves neuro signs | $3,000–$8,000 one-time | Multiple sessions over 3–4 weeks; often combined with trilostane for cortisol control |
| Steroid taper (iatrogenic) | Iatrogenic Cushing's from medication | Full resolution expected with proper tapering | Minimal (vet visit costs) | Must taper slowly over weeks to months; abrupt withdrawal risks Addisonian crisis |
Supportive and Adjunctive Care
Beyond primary treatment, most Cushing's dogs benefit from:
- Dietary management: A diet moderate in protein (20–30% dry matter basis), low in fat (<12%), and low in sodium helps manage concurrent conditions. Prescription diets like Hill's Prescription Diet l/d or Royal Canin Hepatic may be recommended if liver values are elevated.
- UTI prevention: Recurrent urinary tract infections affect up to 50% of Cushing's dogs. Periodic urine cultures (every 3–6 months) and targeted antibiotics when needed.
- Skin and coat support: Omega-3 fatty acid supplements (fish oil at 20–55 mg/kg EPA+DHA daily) support skin barrier repair during coat regrowth.
- Joint support: Muscle wasting puts extra stress on joints. Glucosamine/chondroitin supplements and controlled exercise help maintain mobility.
Prognosis and Life Expectancy for Dogs with Cushing's Disease
What is the life expectancy of a dog with Cushing's disease? Prognosis varies significantly based on the type of Cushing's, the presence of complications, and how early treatment begins. According to data summarized by the Merck Veterinary Manual and peer-reviewed veterinary literature:
| Scenario | Median Survival Time | Key Factors |
|---|---|---|
| PDH managed with trilostane (microtumor) | 2–2.5 years (many live 3–5+ years) | Most common scenario; excellent quality of life with consistent monitoring |
| PDH with pituitary macrotumor (>10mm) | 6–18 months without radiation/surgery | Neurological complications are primary concern; survival improves with radiation |
| ADH — benign tumor, surgically removed | 18 months–4+ years; potential cure | Best-case surgical outcome; some dogs require no further treatment |
| ADH — malignant adrenal carcinoma | 6–12 months | High metastasis rate; surgery may be palliative |
| Iatrogenic Cushing's (steroid withdrawal) | Normal lifespan expected | Full resolution once underlying medication is tapered; adrenal function recovers over weeks to months |
| Untreated Cushing's disease | Variable; typically 1–2 years from symptom onset | Death usually results from complications: diabetes, pancreatitis, kidney failure, pulmonary thromboembolism, or congestive heart failure |
Home Care and Daily Management
Managing a Cushing's dog at home requires consistency. Here's what your daily and weekly routine should look like once treatment is underway:
Daily Tasks
- Administer trilostane or mitotane at the same time each day — trilostane should be given with food to improve absorption. Missing doses causes cortisol levels to rebound.
- Monitor water intake — measure how much water your dog drinks in 24 hours. Normal is roughly 50–60 mL/kg/day. A sudden increase or decrease is clinically significant and should be reported to your vet.
- Watch for signs of over-treatment (Addisonian crisis) — vomiting, diarrhea, lethargy, collapse, loss of appetite. This is a medical emergency. Keep your emergency vet's number accessible.
- Maintain a consistent feeding schedule — two measured meals daily using the diet your vet recommends. Avoid free-feeding despite increased appetite.
- Provide regular, moderate exercise — 20–30 minute walks twice daily help maintain muscle tone without overtaxing a potentially weakened cardiovascular system.
Ongoing Monitoring Schedule
- 10 days after starting trilostane: ACTH stimulation test + electrolytes
- 30 days: ACTH stimulation test + chemistry panel
- 90 days: ACTH stimulation test + full blood work
- Every 3–6 months thereafter: ACTH stimulation test + chemistry panel for life
- Every 6 months: Urine culture (even without symptoms — Cushing's dogs get "silent" UTIs)
- Annually: Abdominal ultrasound to monitor adrenal gland size and liver health
Total Cost of Cushing's Disease Treatment in Dogs
How much does Cushing's disease treatment cost? Budgeting realistically helps you plan for your dog's long-term care. Below is a breakdown of expected costs based on 2026 U.S. veterinary pricing:
| Expense Category | First Year | Each Subsequent Year |
|---|---|---|
| Initial diagnosis (all tests) | $670–$4,280 | N/A |
| Medication (trilostane, ongoing) | $720–$2,400 | $720–$2,400 |
| Monitoring blood work (4× first year, 2× annually) | $600–$1,600 | $300–$800 |
| Annual ultrasound | $300–$600 | $300–$600 |
| Urine cultures (2× per year) | $100–$200 | $100–$200 |
| Supplements (omega-3, joint support) | $120–$300 | $120–$300 |
| Estimated annual total | $2,510–$9,380 | $1,540–$4,300 |
Worst-case scenarios: If your dog develops complications — diabetes mellitus (occurs in ~10% of Cushing's dogs), pancreatitis, or a pulmonary thromboembolism — emergency hospitalization can add $2,000–$8,000+ per event. Pet insurance with no upper payout limit is strongly recommended; expect premiums of $60–$150/month for a senior dog enrolled before diagnosis.
Can Cushing's Disease Be Prevented?
There is no known way to prevent pituitary-dependent or adrenal-dependent Cushing's disease — these arise from spontaneous tumors with genetic and possibly environmental components. However, you can reduce risk in one area:
- Minimize unnecessary corticosteroid use: Discuss steroid-sparing alternatives with your vet for chronic conditions like allergies (e.g., Apoquel®, Cytopoint®, or immunotherapy instead of long-term prednisone).
- Monitor steroid-dependent dogs closely: If your dog must be on long-term steroids, request periodic ACTH stimulation tests to catch iatrogenic changes early.
- Choose responsible breeders: For predisposed breeds, select breeders who screen for endocrine disorders in their breeding stock. The Orthopedic Foundation for Animals (OFA) maintains health databases that responsible breeders use.
When to See the Vet: Red Flag Symptoms
🚨 Seek Immediate Veterinary Care If Your Dog Shows:
- Sudden collapse, extreme lethargy, or inability to stand — possible Addisonian crisis (over-treatment complication) or pulmonary thromboembolism
- Vomiting and diarrhea that doesn't stop within 12 hours — may indicate adrenal insufficiency or pancreatitis
- Seizures, head pressing, or disorientation — suggests pituitary macrotumor growth or severe electrolyte imbalance
- Difficulty breathing or rapid breathing at rest — could signal pulmonary thromboembolism (blood clot in lungs), a known Cushing's complication
- Sudden blindness or vision changes — associated with pituitary tumor compression of the optic chiasm
- Complete loss of appetite in a previously ravenous dog — often the first sign of an Addisonian crisis in treated dogs
- Excessive thirst with no urination for 8+ hours — may indicate kidney failure or urinary obstruction
Emergency resources: ASPCA Animal Poison Control: (888) 426-4435 (24/7, consultation fee applies) if medication overdose is suspected. Otherwise, contact your nearest emergency veterinary hospital immediately.
Non-Emergency but Schedule a Visit Within 1–2 Weeks:
- Gradually increasing thirst and urination over several days
- New or worsening hair loss, especially symmetric patterns on the trunk
- Developing a potbelly appearance without overall weight gain
- Recurrent skin, ear, or urinary tract infections
- Changes in behavior — increased restlessness, nighttime pacing, or panting at unusual times
Frequently Asked Questions About Cushing's Disease in Dogs
Is Cushing's disease painful for dogs?
Cushing's disease itself isn't typically painful in the way a broken bone or infection is. However, the secondary effects — muscle weakness, recurrent skin infections, joint stress from a distended abdomen, and calcium deposits in the skin (calcinosis cutis) — can cause significant discomfort. Many owners report their dog seems "happier" within weeks of starting treatment as these secondary issues resolve.
Should I treat my senior dog's Cushing's disease, or is it kinder to let nature take its course?
This is a deeply personal decision that depends on your dog's overall health, the severity of symptoms, and your capacity for ongoing management. Untreated Cushing's progressively worsens quality of life — the excessive thirst, constant hunger, and recurrent infections are genuinely uncomfortable. Many dogs diagnosed at age 10–12 respond well to trilostane and enjoy 2–3+ additional years of good quality life. Discuss your dog's specific case, comorbidities, and quality-of-life scoring (such as the HHHHHMM scale) with your veterinarian.
Can I give my dog natural or herbal remedies instead of trilostane?
There is no peer-reviewed evidence that herbal supplements (melatonin, lignans, ashwagandha) effectively treat Cushing's disease or reduce cortisol levels to a therapeutic degree. Some supplements may provide mild supportive benefits for coat health or anxiety, but they should never replace FDA-approved medication for a condition as serious as hyperadrenocorticism. Discuss any supplements with your veterinarian, as some can interact with prescribed medications.
Will my dog's hair grow back after treatment?
In most cases, yes — but slowly. Coat regrowth typically begins 3–6 months after cortisol levels normalize and can take 6–12 months for full restoration. Some dogs with long-standing disease may have permanent thinning. Calcinosis cutis lesions may take longer to resolve and can leave scarring.
How often does the trilostane dose need to change?
Dose adjustments are common, especially in the first 6 months. Based on ACTH stimulation test results, your vet may increase the dose, split it into twice-daily dosing (which provides more consistent cortisol control in some dogs), or occasionally decrease it. Once stable, most dogs remain on the same dose for months to years, but dose creep upward is common as the disease slowly progresses.
Aaron Whyte
All our authors care for dogs every day — read more of their work on the authors page.
