The Hometown Veterinarian – Marshalltown, Iowa
Addison’s disease in dogs, or more properly known as hypoadrenocorticism, is a relatively uncommon but serious condition that affects a dog’s ability to manage stress and maintain proper fluid and electrolyte balance. While it may not be as widely recognized as other canine health issues, Addison’s is a condition where early diagnosis and lifelong management can make a world of difference in your dog’s health—and even save their life.
If your dog has been diagnosed with Addison’s disease, or you’re trying to understand its symptoms, this page is here to help walk you through the condition in a clear, compassionate way.
What Is Addison’s Disease?
In a healthy dog, the adrenal glands (located just above the kidneys) produce vital hormones that help regulate metabolism, maintain blood pressure, control electrolytes like sodium and potassium, and support the body’s response to stress. Addison’s disease occurs when these glands fail to produce enough of two essential hormone types:
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Glucocorticoids (like cortisol) – Help the body manage stress, blood sugar, and metabolism
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Mineralocorticoids (like aldosterone) – Regulate sodium, potassium, and hydration
Without these hormones, a dog’s internal systems can become dangerously unbalanced—especially during times of stress.
What Causes Addison’s Disease?
Addison’s disease may develop for several reasons:
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Immune-mediated destruction of the adrenal glands (most common)
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Medication-related suppression (especially long-term steroid use or sudden withdrawal)
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Pituitary dysfunction (in rare secondary Addison’s cases)
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Unknown causes, which are common
Certain breeds may be genetically predisposed, including Standard Poodles, Bearded Collies, Nova Scotia Duck Tolling Retrievers, and Portuguese Water Dogs. Female dogs are diagnosed about twice as often as males.
Symptoms: The Great Imitator
Addison’s disease can be difficult to recognize at first. It often presents with vague, waxing-and-waning symptoms that mimic many other illnesses, including:
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Lethargy or general weakness
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Loss of appetite and weight loss
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Vomiting and/or diarrhea
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Increased thirst and urination
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Shaking or trembling
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Low heart rate
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Occasional collapse or fainting
These symptoms can come and go depending on stress levels, and they’re easy to misinterpret as other issues. This is why Addison’s is often called “The Great Imitator.” In some cases, the disease progresses to a life-threatening Addisonian crisis, which includes collapse, shock, dangerously low blood sugar, and heart rhythm abnormalities due to high potassium levels.
How Is Addison’s Diagnosed?
Because symptoms can resemble other conditions like kidney disease, hypoglycemia, or gastrointestinal disorders, diagnosing Addison’s requires careful veterinary evaluation.
Initial testing may reveal:
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Low sodium and high potassium
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Elevated BUN and creatinine
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Low blood sugar
However, the definitive test is the ACTH stimulation test, which checks whether the adrenal glands can respond appropriately to hormonal stimulation. A dog with Addison’s disease won’t show the expected rise in cortisol after the test.
Types of Addison’s Disease
Addison’s isn’t always the same across patients. Your veterinarian will help determine the form your dog has:
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Typical Addison’s – Deficiency of both glucocorticoids and mineralocorticoids
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Atypical Addison’s – Only glucocorticoids are deficient; sodium/potassium levels are initially normal but may worsen over time
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Secondary Addison’s – Due to pituitary failure; mineralocorticoid production remains intact
Understanding the type helps guide treatment and monitoring strategies.
Treatment and Management
Treatment involves hormone replacement therapy to restore the balance the adrenal glands can no longer maintain. Two main options are available:
1. Oral Medications
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Fludrocortisone – Replaces mineralocorticoids and has mild glucocorticoid activity
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Prednisone – May be added if additional glucocorticoid support is needed
This approach requires daily dosing and periodic bloodwork to monitor sodium and potassium levels.
2. Injectable Option
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DOCP (Percorten-V® or Zycortal®) – An injection every 25–30 days
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Dogs also require daily prednisone alongside DOCP
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This is typically Dr. Jacobson’s preferred approach—and the preference of many veterinarians—because it tends to offer more consistent and reliable electrolyte control. It also simplifies daily management for many pet owners, as the injection is only needed about once a month.
Your veterinarian will guide you in choosing the best approach based on your dog’s needs, your schedule, and cost considerations.
Living with Addison’s Disease
While Addison’s is a lifelong condition, it’s very manageable with proper care. Dogs receiving appropriate treatment can live full, happy lives.
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Keep a consistent routine—minimize stress and avoid sudden changes
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Administer medication as prescribed
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Monitor for signs of imbalance (vomiting, lethargy, loss of appetite)
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Stay current with routine bloodwork
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Work closely with your veterinary team to adjust treatment over time
A Word from The Hometown Veterinarian
At The Hometown Veterinarian, we believe that pet owners should never feel alone when navigating a medical diagnosis. Addison’s disease may seem complex at first, but with the right care plan and consistent veterinary support, your dog can live a vibrant, healthy life.
If you suspect Addison’s disease or your dog has been diagnosed and you want expert guidance on the best course of treatment, we’re here to help.