Cushing's Disease in Dogs: When the Body Makes Too Much Cortisol
Cushing's disease causes the body to produce excess cortisol. Learn about the signs, diagnosis, and treatment of this common endocrine disorder.
Hyperadrenocorticism (Cushing's disease) is a condition where the body produces too much cortisol. It's one of the most common endocrine disorders in middle-aged and older dogs. While it can't be cured, it can be effectively managed, and most dogs with Cushing's live comfortable lives with treatment.
Key Points
- Most common in middle-aged to older dogs
- Excess cortisol affects nearly every organ system
- The hallmark sign is increased thirst and urination
- Most cases are caused by a benign pituitary tumor
- Medication (trilostane) effectively manages the condition
- Regular monitoring is essential for safe treatment
What Is Cushing's Disease?
Cortisol is a stress hormone produced by the adrenal glands. In Cushing's disease, the body produces too much. 80-85% of cases are caused by a small, benign tumor in the pituitary gland (at the base of the brain) that signals the adrenal glands to overproduce cortisol. The remaining 15-20% are caused by an adrenal gland tumor.
Recognizing the Signs
The hallmark signs include: dramatically increased thirst and urination (sometimes drinking several liters per day), increased appetite, pot-bellied appearance, hair loss (especially on the trunk), thin skin, muscle weakness, lethargy, panting, and recurring skin and urinary infections. The signs develop gradually, so owners may not realize how much their dog has changed.
Diagnosis
Diagnosis involves blood tests: the low-dose dexamethasone suppression test (LDDS) and ACTH stimulation test are the most commonly used. Additional tests (urine cortisol:creatinine ratio, abdominal ultrasound) help determine whether the cause is pituitary or adrenal. Accurate diagnosis is important because treatment differs based on the cause.
Treatment
Most cases are treated with trilostane (Vetoryl), which blocks cortisol production. The dose is carefully adjusted based on regular blood tests (ACTH stimulation tests). Treatment is lifelong. Your dog will need regular monitoring — initially every 2-4 weeks, then every 3-6 months once stable. With proper management, most dogs do very well.
When to See a Vet Immediately
- Dramatically increased thirst and urination
- Pot-bellied appearance
- Hair loss on the trunk
- Increased appetite with muscle wasting
- Thin skin or recurring skin infections
- Panting and lethargy in an older dog
How RVC Can Help
RVC diagnoses and manages Cushing's disease with comprehensive testing, trilostane therapy, and regular monitoring. We'll guide you through every step. Call +853 6677 6611.
This article is for educational purposes only and does not replace professional veterinary advice. If your pet is showing any symptoms, please contact Royal Veterinary Center immediately at +853 6677 6611.