Addison’s disease is another name for hypoadrenocorticism, which is the decreased production of hormones in the adrenal glands. It’s less common than Cushing’s Disease (hyperadrenocorticism), which is the overproduction of adrenal hormones.
A dog’s adrenal glands sit on top of the kidneys and have two major parts, the outer cortex and the inner medulla. The glands’ main function is to produce hormones — specifically steroids — that play a huge part in regulating your pup’s bodily systems and internal organs.
The outer cortex, which produces corticosteroids like aldosterone and cortisol (also known as the stress hormone), is affected by Addison’s disease. If dogs don’t have these necessary corticosteroids, their body can start to shut down and eventually cause death.
But there’s good news! Once diagnosed, most cases of Addison’s disease can be managed, and dogs can usually live their full lifespan.
Let’s take a look at everything you need to know about Addison’s disease.
In most cases, the cause of Addison’s disease remains unknown. However, veterinarians believe there are some potential causes including:3
- Autoimmune disorders that destroy adrenal tissue
- Overzealous treatment of Cushing’s disease with drugs that suppress adrenal gland activity too much
- A tumor that has spread to the adrenal glands
Addison’s disease can develop in dogs of any breed (purebred or mixed), age, or sex. But it’s most common in females and young to middle-aged dogs. While Addison’s disease does not discriminate, certain dog breeds are more susceptible to developing the disease, including:3
- Bearded collies
- Great Danes
- Soft-coated wheaten terriers
- West Highland white terriers
- Nova Scotia duck tolling retrievers
- Portuguese water dogs
- Standard poodles
Clinical signs and symptoms of Addison’s disease in dogs don’t usually become apparent until approximately 90% of the adrenal cortex has been destroyed.4 In fact, Addison’s disease can be difficult to diagnose right away because it mimics symptoms from other health conditions so well that it’s nicknamed “The Great Imitator."
Some of the symptoms and clinical signs of Addison’s disease include:3
- Lethargy and depression
- Vomiting and diarrhea
- Increased thirst and urination
- Weight loss
- Intermittent shaking
- Reduced appetite
- Irregular heart rate
These clinical signs can appear suddenly then ebb and flow. They can also worsen when a dog is experiencing stressful conditions because the adrenal glands aren’t producing enough cortisol to manage it.
Sometimes, the disease is severe enough to cause an Addisonian crisis — an episode when a dog collapses as their body goes into shock. This is because the dog’s body can no longer respond adequately to stress due to the decreased production of necessary corticosteroids and an overworked immune system.
Immediate hospitalization and veterinary treatment is needed if this takes place because it can be life-threatening. About 30% of dogs are diagnosed with Addison’s disease when they experience an Addisonian crisis.4
Because Addison’s disease is “The Great Imitator," clinical signs won’t be enough to make a diagnosis. A veterinarian diagnoses using your dog’s history, routine blood work, a full physical examination, and the adrenocorticotropic hormone (ACTH) stimulation test. However, a pet in an Addisonian crisis receives immediate treatment before diagnostic testing takes place.
The ACTH stimulation test is used to definitively diagnose Addison’s disease.5 To perform this test, a veterinarian measures blood cortisol levels in your dog before and after administering ACTH intravenously. ACTH is naturally produced by the pituitary gland and stimulates the adrenal glands to produce cortisol in times of stress.
Cortisol levels that are low before ACTH stimulation and barely budge afterward indicate Addison’s disease. Routine blood work can indicate Addison’s disease by way of an aldosterone deficiency if results show decreased sodium and increased potassium levels.
If your dog has an Addisonian crisis, they receive immediate treatment to stabilize their body and then treatment for managing the disease can begin. If they didn’t experience a crisis, treatment that manages the disease will begin after their diagnosis.
Treatment includes lifelong medication to replace the missing glucocorticoids and mineralocorticoids. Medications usually include daily pills or injections given approximately once a month supplemented with a steroid pill like prednisone.4
Your veterinarian will come up with the right treatment plan for your pup. Don’t try to adjust your dog’s medication on your own — it’s very important to follow your vet’s instructions exactly as they’re given.
Treatment costs for Addison’s disease in dogs vary based on the medication, the dosage interval, and your dog’s weight. You also have to factor in the cost of regular vet visits and blood work that varies based on your specific vet as well as the cost to treat or manage any affiliated health conditions.
Medication costs can run higher for larger dogs than smaller dogs, and you may pay approximately $500 to $3,000 a year just for DOCP medication if your dog is uninsured.6
Managing Addison’s disease is a lifelong commitment. Once treatment begins, ACTH stimulation testing and electrolyte blood testing are done shortly after (and continue at different intervals for the first few months) to adjust the medication dosage for your dog’s specific needs.
After that, blood work will likely be done once or twice a year to monitor electrolyte levels and adjust medication dosages as needed. Minimizing stress is another important aspect of managing this disease as it can help support the regulation of your pup’s immune system.
After diagnosis and the right treatment plan is found, the life expectancy for dogs with Addison’s disease is about the same as a dog without Addison’s, provided their condition continues to be well-managed.
Emergency vet bills and lifelong medication costs can take a toll on your finances and add up quickly. Consider investing in a dog insurance policy with MetLife Pet Insurance.1 Policies may help cover costs and ease your financial burden so you can focus on giving your dog the best life.2 Get your free quote today.