A Primer On Addison’s Disease: What is Addison’s Disease in Dogs?

In dogs, the main cause of Addison’s disease is an immune process. Often, dogs develop Addison’s disease when their immune system destroys adrenal tissue.

Addison’s disease can sometimes develop as a side effect of overtreatment for Cushing’s disease. Further, Addison’s disease can result from suddenly stopping long-term steroid treatment without a gradual withdrawal period.

Other, less common causes include:

  • trauma
  • infection
  • cancer
  • tumor or defect in the pituitary gland

Breeds genetically more vulnerable to this disease include:

  • Standard Poodles
  • Great Danes
  • Labrador Retrievers
A Primer On Addison's Disease: What is Addison's Disease in Dogs?


The adrenal glands are small glands that are located next to the kidneys. They produce hormones that regulate normal body functions.  These hormones include cortisol and aldosterone, which are both essential to health.

In Addison’s disease, aka hypoadrenocorticism, the adrenal glands don’t produce enough of these hormones.

What does it look like

Dogs can show a variety of different symptoms of Addison’s disease, including:

  • lethargy
  • vomiting and diarrhea
  • lack of appetite
  • shaking
  • weakness

Bouts of illness typically “wax and wane.”  

Often, people refer to Addison’s disease as the “Great Imitator.” That is because its signs are usually vague and can mirror a variety of medical disorders. Dogs can intermittently improve with supportive treatments. However, the signs will return once treatment ends.

Addisonian crisis

Addisonian crisis is a life-threatening situation when the hormone levels drop below the levels that sustain function.

Dogs that suddenly start vomiting and having diarrhea and become weak, faint and collapse may be suffering an Addisonian crisis.  

This is an emergency, and you should seek veterinary attention for your dog immediately.

In the above video, Zeus showed up at the veterinary clinic after an acute episode of refusing food and severe lethargy. Because Zeus was a young, active boy, such a drastic change raised a red flag.

The veterinarian assessed his heart, checked for anemia, evidence of obstruction or GI distress. Next, the veterinarian ran full blood work. After ruling out all common suspects, Zeus’s diagnosis was Addison’s disease.

Diagnosing Addison’s disease in dogs

Diagnosis is based on your dog’s history, results of a physical examination, and blood and urine tests.  Additionally, more specialized blood tests confirm the diagnosis. 

The definite text to confirm Addison’s disease is the ACTH-stimulation test. It measures cortisol levels before and after injection of synthetic hormone that regulates the production of the adrenal hormones.

Further, your veterinarian might recommend X-rays or ultrasound to rule out other causes of your dog’s clinical signs.

Treating Addison’s disease in dogs

The treatment of Addison’s disease consists of oral or injectable hormonal replacement medications.

Accurate dosage is essential. Therefore, your vet will monitor your dog’s progress very carefully, especially at the beginning of treatment.  Further, follow-up blood testing is necessary to adjust medication dosages.  Your dog will need the medication for life and may need a higher dose during periods of stress, such as traveling or boarding.

With proper treatment, your dog’s prognosis is good. However, you ought to learn to observe subtle warning signs that your dog’s hormones are are low.

Related articles:
Addison’s Disease in a Chihuahua: Kermit’s Story
Canine Addison’s Disease Awareness: Valentino’s Story
Dog Addison’s Diagnosis: Gracie Lou Clough’s Story
Hannah Gets Ill: Addison’s Disease Awareness—What’s Wrong With Hannah?

Further reading:
Addison’s Disease in Dogs – Overview

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