Early Symptoms, Diagnosis & Treatment Guide
Learn the early and advanced signs of Cushing's in dogs, how veterinarians diagnose it, treatment costs, prognosis, and what to expect managing this endocrine disease.
If your dog has been drinking noticeably more water, leaving puddles on the floor, and developing a rounder belly despite no change in diet, you may be noticing the signs of Cushing's in dogs — a hormonal disorder that affects an estimated 1 to 2 out of every 1,000 dogs, most commonly those over the age of seven. Cushing's disease, clinically known as hyperadrenocorticism (HAC), occurs when the body produces excess cortisol, a steroid hormone normally released in response to stress. In dogs, this overproduction typically stems from a small tumor on the pituitary gland (about 80–85% of cases) or, less commonly, a tumor on one of the adrenal glands (15–20%). A third form, iatrogenic Cushing's, results from prolonged use of corticosteroid medications like prednisone.
Left untreated, Cushing's can lead to diabetes, kidney damage, hypertension, and recurrent infections. The good news: with proper veterinary diagnosis and ongoing management, most dogs with pituitary-dependent Cushing's live comfortably for several years after diagnosis. This guide breaks down the symptom progression, diagnostic process, treatment pathways, and realistic costs you should expect in 2026.
What Is Cushing's Disease in Dogs?
Cushing's disease is an endocrine disorder in which the adrenal glands — two small organs sitting atop each kidney — chronically overproduce cortisol. The process usually begins in the brain: a benign microadenoma (small tumor) on the pituitary gland secretes excessive adrenocorticotropic hormone (ACTH), which signals the adrenal glands to pump out more cortisol than the body needs. This form is called pituitary-dependent hyperadrenocorticism (PDH) and accounts for roughly 80–85% of naturally occurring cases.
In adrenal-dependent hyperadrenocorticism (ADH), which makes up 15–20% of cases, a tumor on one adrenal gland autonomously produces cortisol, independent of pituitary signaling. Approximately half of adrenal tumors are malignant (adrenocortical carcinomas), while the other half are benign adenomas.
Iatrogenic Cushing's develops when dogs receive long-term corticosteroid therapy — for allergies, autoimmune conditions, or inflammatory diseases — at doses that mimic the effects of naturally occurring disease. This form is fully reversible once the medication is tapered under veterinary supervision.
According to the Merck Veterinary Manual, Cushing's is one of the most common endocrine disorders in middle-aged and older dogs, alongside hypothyroidism and diabetes mellitus.
Recognizing the Signs of Cushing's in Dogs
Cushing's develops gradually, and early symptoms are easy to dismiss as normal aging. Many owners don't seek veterinary attention until the disease has progressed significantly. Below is a severity-organized checklist to help you identify where your dog may fall in the symptom timeline.
| Category | Early Warning Signs | Advanced Symptoms |
|---|---|---|
| Thirst & Urination | Increased water intake (polydipsia); asking to go out more frequently | House soiling in previously trained dogs; drinking 2–3x normal volume; urinary accidents overnight |
| Appetite | Noticeably increased hunger (polyphagia); begging more, scavenging | Ravenous appetite with weight redistribution rather than overall gain |
| Body Shape | Mild abdominal rounding | Distinct "pot-bellied" appearance from liver enlargement and abdominal muscle wasting |
| Coat & Skin | Thinning coat along flanks and trunk; slower regrowth after grooming | Bilateral symmetrical hair loss (alopecia); thin, fragile skin; darkened skin patches; recurrent skin infections |
| Muscle & Energy | Mild lethargy; reluctance to jump or climb stairs | Visible muscle wasting in limbs; weakness; panting at rest |
| Reproductive | Irregular heat cycles in intact females | Testicular atrophy in intact males; anestrus in females |
| Other | Mild panting increase | Recurrent UTIs; calcium oxalate bladder stones; elevated blood pressure; neurological signs (with macroadenomas) |
Risk Factors: Which Dogs Are Most Vulnerable?
Cushing's Disease Risk Profile
- Age: Most commonly diagnosed in dogs aged 7–12 years; rare in dogs under 6
- Breed predisposition: Poodles (especially Miniature and Toy), Dachshunds, Beagles, Boston Terriers, Yorkshire Terriers, Boxers, and German Shepherds show higher incidence rates
- Sex: Females are slightly more likely to develop PDH; adrenal tumors show no strong sex predilection
- Size: Small and toy breeds are overrepresented for PDH; larger breeds (over 44 lb / 20 kg) are somewhat more likely to develop adrenal tumors
- Medication history: Dogs on long-term prednisone, dexamethasone, or other glucocorticoids for chronic conditions (allergies, immune-mediated disease, joint pain) carry risk for iatrogenic Cushing's
- Genetics: No single gene has been identified, but familial clustering in Poodle lines suggests heritable components
How Veterinarians Diagnose Cushing's Disease
Diagnosing Cushing's is a multi-step process because no single test provides a definitive answer in every case. Cortisol levels naturally fluctuate throughout the day, and stress can temporarily elevate them, so your veterinarian will typically combine clinical signs with a sequence of screening and differentiating tests.
Step 1 — Initial blood work and urinalysis ($150–$300): A complete blood count (CBC), serum chemistry panel, and urinalysis may reveal patterns consistent with Cushing's: elevated alkaline phosphatase (ALP), elevated cholesterol, dilute urine (low specific gravity), and sometimes elevated blood glucose. These findings are suggestive, not diagnostic.
Step 2 — Low-dose dexamethasone suppression test (LDDST) ($150–$250): This is the most widely used screening test. Your dog receives a small injection of dexamethasone, and blood cortisol levels are measured at baseline, 4 hours, and 8 hours. In a healthy dog, dexamethasone suppresses cortisol production. In a dog with Cushing's, cortisol remains elevated. The LDDST has a sensitivity of approximately 85–95% for PDH but may miss some adrenal-dependent cases.
Step 3 — ACTH stimulation test ($150–$250): This test measures the adrenal glands' response to synthetic ACTH. It has a lower sensitivity (about 60–65% for PDH) but higher specificity, and it serves as the baseline for monitoring treatment response. Many veterinarians run both the LDDST and ACTH stim to build a complete picture.
Step 4 — High-dose dexamethasone suppression test (HDDST) ($100–$200): If Cushing's is confirmed, the HDDST helps differentiate PDH from ADH. A high dose of dexamethasone will suppress cortisol in most PDH dogs but not in those with adrenal tumors. However, this test is not 100% reliable, and some vets skip it in favor of imaging.
Step 5 — Abdominal ultrasound ($300–$600): Ultrasound allows direct visualization of both adrenal glands. Symmetrically enlarged adrenals suggest PDH; one enlarged and one atrophied adrenal strongly suggests ADH. Ultrasound can also identify adrenal tumor invasion into surrounding blood vessels, which affects surgical planning.
Step 6 — Advanced imaging for PDH (if needed): If neurological symptoms are present (circling, head pressing, seizures, behavior changes), a CT or MRI of the brain ($1,500–$3,000) may be recommended to check for a pituitary macroadenoma — a tumor larger than 10 mm that can compress surrounding brain tissue. This occurs in approximately 10–20% of PDH cases over time.
Estimated Diagnostic Cost Summary
| Test | Purpose | Typical Cost Range |
|---|---|---|
| CBC, chemistry, urinalysis | Initial screening | $150–$300 |
| Low-dose dexamethasone suppression test | Confirm Cushing's | $150–$250 |
| ACTH stimulation test | Confirm + baseline for treatment | $150–$250 |
| High-dose dexamethasone suppression test | Differentiate PDH vs. ADH | $100–$200 |
| Abdominal ultrasound | Visualize adrenal glands | $300–$600 |
| Brain CT/MRI (if macroadenoma suspected) | Assess pituitary tumor size | $1,500–$3,000 |
Total initial diagnostic investment: Most owners spend between $800 and $1,600 for a complete diagnostic workup, not including advanced brain imaging.
Treatment Options for Cushing's in Dogs
Whether Cushing's can be cured depends entirely on the form. Pituitary-dependent Cushing's is typically managed long-term with medication rather than cured. Adrenal tumors may be curable through surgery if caught before metastasis. Iatrogenic Cushing's resolves with gradual medication tapering.
| Treatment | Best For | How It Works | Success Rate | Ongoing Cost (Monthly) |
|---|---|---|---|---|
| Trilostane (Vetoryl) | PDH (first-line treatment) | Inhibits cortisol synthesis in adrenal glands | 85–93% clinical improvement within 2–4 weeks | $50–$200 depending on dose/dog size |
| Mitotane (Lysodren) | PDH (older protocol, still used) | Selectively destroys adrenal cortex tissue | 80–90% response rate; higher complication risk | $30–$100 |
| Adrenalectomy | ADH with benign, non-invasive tumor | Surgical removal of affected adrenal gland | Curative in benign cases; 50–60% 2-year survival for carcinomas | N/A (one-time surgery: $3,000–$7,000) |
| Radiation therapy | Pituitary macroadenomas causing neurological signs | Shrinks pituitary tumor over weeks | Improvement in neurological signs in 70–80% of cases; does not normalize cortisol quickly | One-time: $3,000–$6,000 (10–18 sessions) |
| Steroid taper | Iatrogenic Cushing's | Gradually reduce exogenous corticosteroid dose | Fully reversible over weeks to months | Decreasing medication cost |
Trilostane (brand name Vetoryl) has been the standard-of-care medication for PDH since receiving FDA approval and is the treatment most veterinary internists recommend as of 2026. It comes in 5 mg, 10 mg, 30 mg, 60 mg, and 120 mg capsules, and is typically administered once or twice daily with food. Your veterinarian will determine the dose based on your dog's weight, baseline ACTH stimulation results, and follow-up testing. Most dogs begin showing reduced thirst, appetite, and urination within 10–14 days of reaching an effective dose.
Important: Both trilostane and mitotane require careful dose titration and regular monitoring. Over-suppression of cortisol can cause an Addisonian crisis (hypoadrenocorticism), a potentially life-threatening emergency characterized by vomiting, diarrhea, collapse, and dangerously low blood pressure. Never adjust your dog's Cushing's medication dose without consulting your veterinarian.
Prognosis and Life Expectancy
Prognosis varies significantly depending on the underlying cause, tumor type, and how early the disease is caught. Here is what the veterinary literature and clinical data tell us:
| Condition | Median Survival Time (with treatment) | Key Prognostic Factors |
|---|---|---|
| PDH — microadenoma (tumor <10 mm) | 2–2.5 years; many dogs live 3–5+ years | Excellent quality of life with medication compliance and monitoring |
| PDH — macroadenoma (tumor ≥10 mm) | 6–18 months, depending on neurological involvement | Radiation therapy can extend survival; prognosis worsens with brain compression signs |
| ADH — benign adenoma (surgically removed) | Curative; normal life expectancy if surgery is successful | Surgical complication rate approximately 10–15%; contralateral adrenal must recover function |
| ADH — malignant carcinoma | 6–18 months post-surgery; shorter if metastasis present | Vascular invasion, tumor size >5 cm, and metastasis to liver/lungs worsen prognosis |
| Iatrogenic Cushing's | Fully reversible; normal life expectancy after tapering | Recovery timeline depends on duration and dose of prior steroid use |
According to studies published in the American Journal of Veterinary Research, dogs with well-managed PDH who receive consistent medication and monitoring have quality of life scores comparable to healthy dogs of the same age. The most common causes of death in treated Cushing's dogs are unrelated conditions (cancer, kidney disease, heart disease) rather than Cushing's itself.
Home Care and Daily Management
Managing a dog with Cushing's is a long-term commitment, but it becomes routine once you establish a system. Here is what daily life looks like:
Medication Administration
Trilostane should be given with food to improve absorption. Administer it at the same time(s) each day. If you miss a dose, give it as soon as you remember unless it is close to the next scheduled dose — never double-dose. Store capsules at room temperature, away from moisture. Always wear gloves when handling trilostane capsules, as the medication can be absorbed through human skin; pregnant women should avoid handling it entirely.
Monitoring at Home
- Track water intake: Measure how much water your dog drinks daily using a marked water bowl or bottle. Record it in a notebook or app. A sustained increase after treatment is stabilized may indicate the dose needs adjustment.
- Monitor appetite and body condition: Use a body condition score (BCS) chart monthly. The goal is a BCS of 4–5 on a 9-point scale.
- Watch for Addisonian signs: Vomiting, diarrhea, lethargy, weakness, or collapse while on trilostane or mitotane is an emergency. Stop the medication and contact your veterinarian immediately.
- Observe coat and skin: Hair regrowth can take 3–6 months after cortisol normalizes. Note any new bald patches or skin infections.
Veterinary Monitoring Schedule
After starting trilostane, your vet will typically run an ACTH stimulation test at 10–14 days, then at 30 days, then at 90 days, and every 3–6 months thereafter for the life of the dog. Each monitoring visit, including the ACTH stim test and exam, typically costs $200–$400. Dose adjustments are common — approximately 40% of dogs need at least one dose change in the first year.
Diet and Exercise
Dogs with Cushing's benefit from a diet that is moderate in fat (to help manage hyperlipidemia, which is common), high in digestible protein (to counteract muscle wasting), and controlled in sodium (especially if hypertension is present). Many veterinary therapeutic diets, such as Hill's Prescription Diet w/d or Royal Canin Veterinary Diet Gastrointestinal Low Fat, meet these criteria. Always confirm with your veterinarian before switching diets. Maintain regular, moderate exercise — short daily walks and gentle play — adjusted to your dog's energy and muscle strength.
Treatment Costs: What to Budget
Cushing's is a chronic condition that requires ongoing financial commitment. Here is a realistic cost breakdown for 2026:
| Expense Category | First Year | Each Subsequent Year |
|---|---|---|
| Initial diagnostics (full workup) | $800–$1,600 | $0 |
| Trilostane medication (Vetoryl) | $600–$2,400 | $600–$2,400 |
| Monitoring visits (ACTH stim + exams) | $800–$1,600 (4–5 visits) | $400–$800 (2 visits) |
| Abdominal ultrasound (if repeated) | $300–$600 | $0–$600 |
| Treatment of complications (UTIs, skin infections) | $100–$500 | $100–$400 |
| Estimated total | $2,600–$6,700 | $1,100–$4,200 |
Worst-case scenario: If your dog has an adrenal tumor requiring surgery ($3,000–$7,000) or a pituitary macroadenoma requiring radiation therapy ($3,000–$6,000), first-year costs can reach $8,000–$15,000. Pet insurance can offset a significant portion if Cushing's is diagnosed after the policy's waiting period and is not classified as a pre-existing condition. Most comprehensive policies with $5,000–$10,000 annual limits will cover the majority of ongoing Cushing's management.
When to See the Vet Immediately
Red Flag Symptoms — Seek Veterinary Care Now
- Sudden collapse, extreme weakness, or inability to stand — possible Addisonian crisis from over-medication or adrenal tumor hemorrhage
- Vomiting and diarrhea that does not resolve within 12 hours — may indicate cortisol underproduction or pancreatitis
- Seizures, disorientation, head pressing, or circling — possible pituitary macroadenoma expansion
- Difficulty breathing or rapid, labored panting at rest — could indicate pulmonary thromboembolism, a known complication of Cushing's
- Sudden, severe increase in thirst and urination with lethargy — may signal diabetes mellitus as a secondary development
- Distended, painful abdomen — possible liver enlargement or, rarely, adrenal tumor rupture
If you observe any of these symptoms in a dog currently being treated for Cushing's, stop the trilostane or mitotane immediately and contact your veterinarian or the nearest emergency clinic. For suspected poisoning or medication overdose, you can also contact the ASPCA Animal Poison Control Center at (888) 426-4435 (24/7, consultation fee applies).
Can Cushing's Disease Be Prevented?
Naturally occurring Cushing's disease (PDH and ADH) cannot be prevented — pituitary and adrenal tumors arise spontaneously, and no screening protocol exists to identify at-risk dogs before symptoms develop. However, you can reduce the risk of iatrogenic Cushing's by working with your veterinarian to use the lowest effective dose of corticosteroids for the shortest possible duration. For chronic conditions like allergies, ask your vet about steroid-sparing alternatives such as oclacitinib (Apoquel), lokivetmab (Cytopoint), or allergen-specific immunotherapy.
For breeds with known predisposition, being vigilant about early signs — especially increased thirst, urination, and appetite in dogs over age 7 — allows for earlier diagnosis and treatment initiation, which improves long-term outcomes.
Frequently Asked Questions
Is Cushing's disease in dogs painful?
Cushing's itself is not typically painful, but the secondary complications it causes can be uncomfortable. Recurrent skin infections cause itching, urinary tract infections cause discomfort, and muscle wasting can lead to joint strain and mobility difficulty. Dogs with large pituitary tumors may experience headaches or neurological discomfort. Most dogs on well-managed treatment appear comfortable and active.
Can diet alone treat Cushing's disease?
No. There is no diet, supplement, or natural remedy proven to normalize cortisol production in dogs with Cushing's. While a balanced, appropriate diet supports overall health and helps manage secondary issues like hyperlipidemia and muscle wasting, medical treatment with trilostane or surgical intervention is required to address the underlying hormonal imbalance. Be cautious of online products claiming to cure Cushing's naturally — these are not supported by veterinary evidence and delaying proper treatment can worsen the disease.
What breeds are most prone to Cushing's disease?
The breeds with the highest reported incidence of Cushing's include Poodles (particularly Miniature and Toy), Dachshunds, small Terriers (Yorkshire, Boston, Cairn), Beagles, and Boxers. However, any breed can develop Cushing's, and mixed-breed dogs are also affected. Breed predisposition should inform your vigilance, not limit your concern to specific breeds.
Will my dog's hair grow back after Cushing's treatment?
In most cases, yes. Hair regrowth typically begins 3–6 months after cortisol levels are stabilized with medication. The coat may come back slightly different in texture or color initially. Some dogs with prolonged, untreated Cushing's may have permanent thinning, particularly if the skin became severely atrophied. Addressing secondary skin infections promptly also supports better coat recovery.
How often does my dog need blood work once diagnosed?
After initial dose stabilization (which requires tests at roughly 2 weeks, 4 weeks, and 12 weeks), most dogs need an ACTH stimulation test and veterinary exam every 3–6 months for life. Your vet may adjust this frequency based on how stable your dog's cortisol levels remain. Senior dogs or those with comorbidities like diabetes or kidney disease may need more frequent monitoring.
Should I see a veterinary specialist for Cushing's?
Most general practice veterinarians manage uncomplicated PDH cases effectively. However, referral to a veterinary internal medicine specialist (DACVIM) is advisable if your dog has an adrenal tumor requiring surgery, a pituitary macroadenoma, does not respond to standard trilostane therapy, or develops significant complications. Specialist consultations typically cost $200–$350 for the initial visit, with procedure costs varying by case complexity.
This article is for informational purposes and does not replace professional veterinary advice. If you suspect your dog is showing signs of Cushing's disease, consult your veterinarian for proper diagnosis and treatment planning. Individual cases vary, and only a licensed veterinarian who has examined your dog can make diagnostic and treatment decisions.
Aaron Whyte
All our authors care for dogs every day — read more of their work on the authors page.
