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Cushing’s disease (hyperadrenocorticism) is one of the most common hormonal disorders in middle-aged and senior dogs: the body chronically produces too much cortisol. Because the signs creep in slowly — and look a lot like “just getting old” — many dogs go undiagnosed for years. Here is what to watch for and how the condition is managed.
Symptoms of Cushing’s Disease in Dogs
- Drinking and urinating far more than before (often the first sign)
- Ravenous appetite
- Pot-bellied appearance with muscle loss in the legs
- Thinning skin, hair loss along the body (often symmetrical), slow wound healing
- Panting at rest, lethargy, recurrent skin and urinary infections
What Causes It
About 80-85% of cases are pituitary-dependent — a small benign tumor of the pituitary gland over-signals the adrenals. The rest are adrenal tumors, or iatrogenic Cushing’s from long-term steroid medication. Breeds at higher risk include Poodles, Dachshunds, Boston Terriers, Boxers and Beagles.
How Vets Diagnose It
No single perfect test exists. Vets typically combine blood work and urinalysis with an ACTH stimulation test or low-dose dexamethasone suppression test, plus ultrasound to check the adrenals. Diagnosis matters because treating a dog who doesn’t actually have Cushing’s is genuinely harmful — insist on confirmation before starting medication.
Treatment and Management
Medication — trilostane (Vetoryl) is the standard; it blocks cortisol synthesis and requires periodic monitoring tests. Surgery — an option for some adrenal tumors. Supportive care — this is where owners make a daily difference:
- Sleep and restlessness: high cortisol disrupts the sleep-wake cycle; many dogs pace at night. Vets sometimes suggest melatonin as a gentle adjunct — it may mildly counter abnormal hormone signaling and helps restore night-time settling. A dog-specific melatonin for dogs with weight-based dosing is the safe way to trial it (see our guide on whether dogs can have melatonin).
- Skin and coat: thinning skin and recurrent infections respond to gentle grooming and skin-barrier support — our senior grooming guide applies directly.
- Recurrent infections: yeast overgrowth thrives on cortisol-suppressed immunity; our yeast infection guide covers breaking that cycle.
Prognosis
Cushing’s is rarely cured but very manageable: most medicated dogs regain energy, regrow coat and live good-quality lives. The keys are accurate diagnosis, consistent monitoring, and patient day-to-day care. More senior health guides at Dog Health Insider.
Scientific References
- Behrend EN, Kooistra HS, Nelson R, et al. Diagnosis of spontaneous canine hyperadrenocorticism: 2012 ACVIM consensus statement. J Vet Intern Med. 2013;27(6):1292-1304. (PubMed)
- Ramsey IK. Trilostane in dogs. Vet Clin North Am Small Anim Pract. 2010;40(2):269-283. (PubMed)
- Frank LA, Donnell RL, Kania SA. Oestrogen receptor evaluation in Pomeranian dogs with hair cycle arrest (alopecia X) on melatonin supplementation. Vet Dermatol. 2006;17(4):252-258. (PubMed)
Always consult your veterinarian before adding any supplement to a Cushing’s management plan — cortisol disorders require professional monitoring.