Cushing’s disease, also known as hyperadrenocorticism, is a hormonal disorder that occurs when a dog’s body produces too much cortisol. While cortisol is essential for regulating metabolism, stress response, and immune function, too much of it can cause serious health issues.
What Causes Cushing’s Disease?
Cushing’s disease is typically caused by one of three factors:
- Pituitary Tumor (Pituitary-Dependent Cushing’s – PDC): This accounts for about 85% of cases. A benign tumor in the pituitary gland overstimulates the adrenal glands, leading to excessive cortisol production.
- Adrenal Tumor (Adrenal-Dependent Cushing’s – ADC): A tumor in one of the adrenal glands can cause them to overproduce cortisol. These tumors may be benign or malignant.
- Long-Term Steroid Use (Iatrogenic Cushing’s): Chronic use of corticosteroids (like prednisone) for allergies or other conditions can cause Cushing’s disease by mimicking excessive cortisol production.
Signs & Symptoms of Cushing’s Disease
Cushing’s develops slowly over time, and symptoms may be mistaken for normal aging. Some common signs include:
- Excessive thirst & urination (drinking and peeing more than usual)
- Increased appetite
- Pot-bellied appearance
- Hair loss & thinning coat
- Thin skin & slow wound healing
- Muscle weakness & lethargy
- Panting more than normal
- Recurring skin infections
- Behavioral changes (restlessness, anxiety, irritability)
How is Cushing’s Disease Diagnosed?
Because symptoms overlap with other conditions (like diabetes or kidney disease), diagnosis requires multiple tests, including: ✔️ Bloodwork (CBC & Chemistry Panel) – Checks for abnormalities like elevated liver enzymes. ✔️ Urine Tests – A Urine Cortisol:Creatinine Ratio (UCCR) can help determine if further testing is needed. ✔️ ACTH Stimulation Test – Evaluates how the adrenal glands respond to hormone stimulation. ✔️ Low-Dose Dexamethasone Suppression Test (LDDST) – The gold standard test to confirm Cushing’s. ✔️ Ultrasound or MRI – Helps determine if an adrenal tumor is present.
Treatment Options
Treatment depends on the cause of Cushing’s disease: 🔹 Pituitary Tumor (PDC): Medications like Trilostane (Vetoryl) or Mitotane (Lysodren) help control cortisol production. Surgery is not an option in most cases. 🔹 Adrenal Tumor (ADC): If the tumor is benign, surgical removal of the affected adrenal gland can be curative. If malignant, treatment is more complex and depends on tumor spread. 🔹 Iatrogenic Cushing’s: If caused by steroid use, the vet will gradually reduce the medication under supervision.
Prognosis & Quality of Life
With proper management, many dogs with Cushing’s disease can live for years with a good quality of life. However, untreated Cushing’s can lead to severe complications, including high blood pressure, diabetes, infections, and increased risk of blood clots. Regular vet visits, bloodwork monitoring, and medication adjustments are key to keeping your pet comfortable and healthy.
Final Thoughts
Cushing’s disease is a lifelong condition, but with early diagnosis, proper treatment, and supportive care, dogs can continue to live happy lives. If you notice any of the symptoms mentioned above, consult your veterinarian as soon as possible. The sooner Cushing’s is diagnosed, the better the chances of managing it effectively!



