You know your dog’s patterns well, it can be incredibly frustrating when something feels off, but you can’t quite put your finger on what it is. You might see a day where they seem a bit sluggish, followed by three days where they are perfectly fine. Then, they might skip a meal, only to have a ravenous appetite the next morning.
In some cases, these “waxing and waning” signs could indicate a condition we see frequently here at Portland Veterinary Emergency and Specialty Care: Addison’s disease in dogs.
What is Addison’s Disease in Dogs?
Addison’s disease in dogs, known medically as hypoadrenocorticism, is a serious hormonal disorder. It occurs when the adrenal glands—two small glands located just in front of the kidneys—stop producing the hormones your dog needs to survive.
Think of the adrenal glands as the body’s “regulatory center.” They produce two essential types of hormones:
- Cortisol (Glucocorticoids): This is the body’s natural stress responder. It helps regulate metabolism, maintains blood pressure, and allows the body to handle everything from a trip to the groomer to a loud thunderstorm.
- Aldosterone (a mineralocorticoid): This is the master regulator of electrolytes. It influences the kidneys to keep sodium and excrete potassium in a delicate balance, which is vital for heart health, hydration, blood pressure maintenance and other physiologic needs.
In an Addison’s dog, the most common cause of the disease is when the immune system mistakenly attacks the adrenal glands. By the time we see clinical signs, about 90% of the adrenal tissue has usually been damaged. Without these hormones, the body loses its ability to maintain internal balance, leading to the varied signs owners often report.
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What are the signs of Addison’s Disease in Dogs?
The most difficult part about identifying Addison’s disease in dogs is that it doesn’t have one “signature” sign. Instead, it presents with signs that look like many other common issues, such as a simple stomach bug or even just the slowing down that can come with age. This is how it gets its well known title of “the great pretender”.
If you are monitoring your dog at home, keep an eye out for these common signs:
- Intermittent Lethargy: Your dog seems unusually tired or “flat” for no clear reason.
- Decrease or periodic loss of Appetite: They may become a “picky eater” overnight or show a complete lack of interest in food.
- Gastrointestinal Upsets: Bouts of vomiting or diarrhea that seem to resolve and then return a week later.
- Unexplained Shaking: Trembling or muscle weakness, often during or after a stressful event.
- Increased Thirst and Urination: You might be filling the water bowl more often than usual.
- Weight Loss: A slow, steady drop in weight despite no changes in their diet.
Because signs of Addison’s disease in dogs come and go, many owners initially suspect a minor virus or a food sensitivity. However, if these issues keep recurring—especially after a stressful event—it’s time to look deeper.
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The “Addisonian Crisis”: A Medical Emergency
In some cases, the disease remains hidden until the hormone levels drop so low that the dog’s body can no longer compensate. This leads to what we call an Addisonian Crisis. Intense periods of stress such as visiting a new place of being boarded can bring on acute crisis.
During a crisis, a dog may suddenly collapse, have a dangerously low heart rate, or show signs of severe shock. This is a life-threatening emergency. If your dog ever collapses or becomes extremely weak and unresponsive, please get them to an emergency facility immediately. The emergency room at PVESC is open 24/7. While a crisis is scary, it is often the moment we are finally able to diagnose the underlying cause and begin life-saving treatment.
Who is at Risk for Becoming an Addison’s Dog?
While any dog can develop this condition—male or female, purebred or mixed—we do see it more frequently in young to middle-aged female dogs. Certain breeds also have a higher genetic predisposition, including:
· Standard Poodles
· West Highland White Terriers
· Great Danes
· Bearded Collies
· Portuguese Water Dogs
Diagnosis: How We Find the Answer
If we suspect your pup is an Addison’s dog, we start with a standard blood panel. We specifically look at the “Na:K ratio”—the balance between sodium and potassium. If the sodium is low and the potassium is high, it’s a major red flag for the disease. A good screening test is a single baseline cortisol measurement.
To be 100% certain, we perform a specialized test called the ACTH Stimulation Test. We measure a baseline cortisol level, give a small injection of a synthetic hormone that should stimulate the adrenals, and check the levels again shortly after. If the adrenal glands are healthy, the cortisol will rise significantly. If the dog has Addison’s, the cortisol levels will remain flat.
Life with an Addison’s Dog: The Road Ahead
While an Addison’s diagnosis feels heavy, it is one of the most rewarding conditions we treat. Why? Because once we start hormone replacement therapy, these dogs don’t just “get better”—they often act like puppies again.
Treatment is for life, but it is very manageable. It typically involves:
1. Replacing the “Salt-Regulator”: Most dogs receive an injection (like DOCP) about once a month that keeps their electrolytes in perfect balance.
2. Replacing the “Stress-Hormone”: A small daily dose of an oral steroid (like Prednisone) replaces the cortisol the body can no longer make.
As your dog’s care team, we work with you to find the “sweet spot” for these dosages. We also teach you how to “pre-treat” for events that are normally stressful to imitate the bodies natural rise in cortisol. If you know you’re going on a road trip or having guests over, you’ll give a slightly higher dose of the oral steroid to help your dog’s body handle the extra excitement.
Trust Your Instincts
At Portland Veterinary Emergency and Specialty Care, we see ourselves as your partners in your dog’s health. You are the expert on your dog’s personality and quirks. If you feel like your dog is “fading” or just hasn’t been themselves lately, don’t wait for a crisis to happen.
Addison’s disease in dogs can be difficult to spot, but it’s no match for a proactive owner and a dedicated veterinary team. With the right diagnosis, your dog can go back to being the happy, energetic companion you know and love.
Are you concerned that your dog’s signs might be more than just a passing bug? Contact us today to schedule a consultation or to discuss what diagnostic testing is right for your dog.
