Addison’s Disease (Hypoadrenocorticism) in Dogs – Vet Diagnosis and Treatment Guide for 2025 🐶🩺⚖️

Addison's disease, or hypoadrenocorticism, is a rare but serious hormonal disorder affecting dogs. It occurs when the adrenal glands, located near the kidneys, fail to produce enough corticosteroids. In this comprehensive 2025 guide, Dr Duncan Houston covers causes, clinical signs, diagnostic challenges, treatment options, and how to manage this condition for optimal pet health. 🩺❤️

🧬 What Are Corticosteroids?

• Glucocorticoids (e.g., cortisol): regulate metabolism and stress responses
• Mineralocorticoids (e.g., aldosterone): manage electrolytes like sodium and potassium

These hormones help pets adapt to stress, maintain fluid balance, and regulate blood pressure and energy. 🌡️

⚠️ What Happens in Addison's Disease?

In Addison's disease, dogs can't produce enough glucocorticoids and/or mineralocorticoids. This hormonal deficiency can lead to shock during stressful events and impair the body's ability to regulate blood sugar and electrolytes. The cause may be autoimmune, idiopathic, drug-induced, or due to adrenal trauma. 🧫

🤔 Clinical Signs

• ❄️ Lethargy or listlessness
• 🤢 Vomiting or diarrhea
• 🚫 Poor appetite
• 📆 Waxing and waning of symptoms
• ⚡ Addisonian crisis: collapse, shock, low blood sugar, high potassium, arrhythmias

Affected breeds include Standard Poodles, Bearded Collies, Portuguese Water Dogs, and Nova Scotia Duck Tolling Retrievers. Females are twice as likely to be affected. 🙌

🧪 Diagnosing "The Great Imitator"

Addison's disease mimics many other illnesses, making diagnosis tricky. It can resemble:

• 💔 Kidney disease
• 🍜 Gastrointestinal disorders
• 🦆 Insulinoma (low blood sugar seizures)
• 👀 Megaesophagus

ACTH stimulation test is the gold standard. It evaluates adrenal response to synthetic ACTH. A flat or low response confirms Addison’s. Only dexamethasone should be used before testing to avoid false results. A baseline cortisol level >2.0 µg/dL can rule out the disease. ⚖️

🚑 Emergency Treatment

• ⛽ IV fluids (Lactated Ringers)
• 💉 Glucocorticoids (typically dexamethasone)
• ☕ Dextrose for hypoglycemia
• ⚡ ECG to monitor cardiac arrhythmias

Dogs often stabilize quickly with appropriate care. 🌟

💊 Long-Term Treatment Options

Two main strategies:

• Fludrocortisone (Florinef®): oral tablet 2x daily, with or without prednisone
• DOCP injection (Percorten-V®, Zycortal®): given every ~25 days + daily low-dose prednisone

Electrolytes must be monitored regularly. DOCP offers better regulation but requires added glucocorticoid. 💉

🌍 Atypical & Secondary Addison’s

• Atypical Addison's: Only glucocorticoids are deficient. No electrolyte imbalance. Treated with prednisone alone. May progress to typical Addison’s. ⏳
• Secondary Addison’s: Pituitary gland fails to produce ACTH. No mineralocorticoid replacement needed. 🧠

⚠️ Conditions That Mimic Addison’s

• 🌿 Whipworm infection (can mimic crisis)
• 🌊 Pacific Rim breeds (e.g., Akitas) may show high potassium without Addison’s

🚀 Prognosis

With appropriate hormone replacement and monitoring, dogs with Addison’s disease can lead full, active lives. Most owners report dramatic improvements once treatment begins. ❤️🌟

📢 Ask A Vet

Suspect Addison’s in your dog? Use the Ask A Vet app to connect with licensed veterinarians, discuss ACTH testing, treatment protocols, and follow-up schedules. 📲