What is Addison’s Disease in Dogs
Addison's disease, also known as hypoadrenocorticism, is a condition in dogs where the adrenal glands don't produce enough of certain essential steroid hormones. These hormones, cortisol and aldosterone, are vital for regulating various bodily functions like electrolyte balance, blood pressure, and stress response. Without enough of these hormones, dogs can experience a range of symptoms, and in severe cases, it can be life-threatening.
Causes Addison’s disease in dogs:
- Mostly caused by an autoimmune response where the dog's immune system attacks and damages the adrenal glands
- Less commonly caused by damage to the adrenal glands due to infection, trauma, or treatment for Cushing’s disease, sudden stop of long-term use of steroid treatment.
Written by Dr. Mariella Roberts, Veterinary Surgeon, Animal Trust Vets CIC | Published October 2025 | Review date October 2028 | This advice is for UK pets only and is not a replacement for seeing a vet
Signs of Addison’s Disease in Dogs
Early symptoms can be vague and easily mistaken for other illnesses, including:
Lethargy and weakness
Not eating and weight loss
Increased thirst and passing urine
Muscle weakness
In severe cases, called an Addisonian crisis, dogs may experience:
Dehydration
Low body temperature
Slow heart rate
Shock and collapse
Bloody stools
When to contact your vet
Make an appointment with your vet if any of the above signs appear, especially if they worsen or progress to an Addisonian crisis, you should contact us immediately as the condition is an emergency.
Diagnosis
Medical history and physical examination
Blood and urine tests, including electrolyte levels
ACTH stimulation test which measures adrenal gland function
Possible additional other tests such as x-rays and ultrasound to rule out other causes
Treatment for Addison’s disease
Addison's disease requires lifelong management with medications:
Hormone (Zycortal) mineralocorticoid given monthly as an injection
Steroids (glucocorticoid) tablets given daily by mouth
In an Addisonian crisis (severe symptoms), intensive care with the use of fluids and minerals (electrolyte) correction into the vein and keeping your dog in the hospital is essential
With far less common ‘Atypical Addison which only affects cortisol production, mineralocorticoid supplementation is not necessary, making steroids (glucocorticoid) the sole hormone replacement needed
Preventing Addison’s disease in dogs
Addison’s disease is not typically preventable. The primary form, where the immune system attacks the adrenal glands, has an unknown cause. However, regular veterinary checkups and prompt treatment of secondary Addison's (caused by pituitary or adrenal gland issues or medication side effects) are crucial for management and preventing crises
Outlook
The outlook for dogs with Addison's disease is generally good with proper treatment and management. While there is no cure, most dogs can live a normal, healthy life with lifelong medication and monitoring.