Addison’s Disease in Dogs: Symptoms and More

Addison’s disease in dogs is a condition caused by a deficiency in steroid hormones.

These hormones are produced by the adrenal glands, tiny organs near the kidneys.

Steroid hormones, specifically cortisol and aldosterone, are produced to counteract stress and to maintain electrolyte balance.

What Is Addison’s Disease in Dogs?

Addison’s disease generally develops when a dog’s immune system attacks and destroys the adrenal glands. It’s most common in female dogs who are young to middle-aged.

Dogs with symptoms of Addison’s disease should be seen promptly by a veterinarian.

If the disease is left untreated, affected dogs can experience an Addisonian crisis, which is a life-threatening condition that warrants immediate medical attention.

Addisonian Crisis in Dogs

An Addisonian crisis, due to lack of steroid hormones, refers to an abrupt onset of worrisome symptoms, such as weakness or collapse, vomiting, extreme lethargy, and trembling.

This can occur if Addison’s disease is left untreated and the dog no longer can cope with stress. It is considered a medical emergency that warrants immediate treatment.

Symptoms of Addison’s Disease in Dogs

Addison’s disease in dogs causes a variety of symptoms, which include the following:

• Increased thirst

• Increased urination

• Trembling

• Lethargy

• Weakness

• Decreased appetite

• Diarrhea (which causes significant loss of sodium and water)

• Vomiting

• Weight loss

• Abdominal pain

• Collapse

Causes of Addison’s Disease in Dogs

Many cases of Addison’s disease are idiopathic, meaning they develop without a known cause.

However, it is likely that any of the following reasons may contribute to the disease in dogs:

• Immune-mediated—Dogs can develop Addison’s disease when their own immune system attacks their adrenal glands.

• Adrenal gland damage—Anything that causes damage to the adrenal glands— including infection, cancer, or inadequate blood supply—can result in Addison’s disease.

• Medication—Dogs who are given medication to treat another endocrine disorder, Cushing’s disease, may develop Addison’s disease if the dosage is inappropriate or if the medication is taken long-term and then stopped abruptly.

• Pituitary gland disease—The pituitary gland, a tiny gland situated at the base of the brain, produces hormones that stimulate the adrenal glands. If there is a problem within the pituitary gland, the adrenal glands might not be stimulated to produce steroid hormones, which can then result in Addison’s disease.

• Breed predisposition—Several breeds, including Great Danes, Standard Poodles, and West Highland White Terriers, are at an increased risk for developing Addison’s disease, likely due to genetics.

How Veterinarians Diagnose Addison’s Disease in Dogs

If you are concerned that your pup may have Addison’s disease, consult your veterinarian.

Be sure to discuss when your dog’s symptoms began and whether your dog has been taking any medications.

Your veterinarian will complete a thorough physical exam to check for abnormalities, such as dehydration or weakness.

If your veterinarian suspects Addison’s disease, they will order diagnostic testing, which might include:

• Blood work—Your vet can take a small sample of blood to look for signs of dehydration, electrolyte imbalance, anemia, or increased kidney values.

• Urinalysis—Your vet can take a urine sample to check your dog’s urine concentration. Addison’s disease results in less concentrated urine than normal, since your pup is drinking more water.

• ACTH stimulation—Your vet will take a sample of blood to check resting cortisol levels. Then they will inject a medication called ACTH, wait an hour, and collect another blood sample.

  • Dogs with Addison’s disease will have low cortisol values for both blood draws. This is the preferred method of confirming a diagnosis of Addison’s disease.

• Imaging—Your vet might order tests such as ultrasound to check for abnormally small adrenal glands, which would indicate an underlying disease.

Treatment of Addison’s Disease in Dogs

Addison’s disease in dogs can’t be cured. It must be managed for the remainder of your dog’s life. Treatment is based on the severity of symptoms and the stage of disease.

Dogs with early Addison’s disease typically receive oral steroids, such as prednisone, and a monthly steroid injection at a veterinary hospital.

Additionally, dogs in Addisonian crisis require hospitalization and intensive supportive care, including intravenous fluids to correct dehydration and electrolyte imbalances.

They might also be given antacids, such as famotidine, and supplemental glucose.

After your pup’s diagnosis of Addison’s disease and initial treatment, your vet will recheck your dog’s blood work in about a month to make sure the dosage of medications is appropriate to control the disease.  

Recovery and Management of Addison’s Disease in Dogs

Most dogs who are diagnosed with Addison’s disease and receive prompt treatment have a noticeable improvement in their symptoms within 24 hours.

Dogs who do not receive treatment or who come to the veterinary hospital in an Addisonian crisis can quickly die, so prompt intervention is key. Fortunately, with prompt treatment, most dogs do fully recover.  

If your pup has Addison’s disease, it’s important to bring them to the vet on time for their monthly injections and to give oral medications exactly as prescribed to best manage this disease.

Prevention of Addison’s Disease in Dogs

Unfortunately, Addison’s disease in dogs is not a preventable condition. It’s likely there is an underlying hereditary component to the disease, but the true cause is unknown.

However, regular veterinary checkups promote your dog’s overall health. They allow a veterinarian to catch early signs of disease so that appropriate treatment can be started before conditions progress in severity.