Addison's Disease in Dogs (Hypoadrenocorticism)
Insufficient adrenal hormone production, sometimes called "the great pretender" for its vague, waxing-and-waning signs that mimic many other diseases.
Overview
Addison's disease results from insufficient production of adrenal hormones, most commonly from immune-mediated destruction of the adrenal glands. Young to middle-aged female dogs are somewhat overrepresented. Signs are often vague, which can make this condition tricky to recognize early.
Clinical signs
- Vague, waxing and waning lethargy
- Decreased appetite, vomiting, and diarrhea
- General weakness
- In an acute crisis ("Addisonian crisis"): collapse, severe weakness, and shock - a medical emergency
Diagnosis
- Bloodwork often shows characteristic electrolyte changes (low sodium, high potassium), though these are not always present ("atypical Addison's")
- Baseline cortisol as a screening tool
- ACTH stimulation test as the definitive diagnostic test
Treatment
- Lifelong hormone replacement - typically desoxycorticosterone pivalate (DOCP) injections or oral fludrocortisone for mineralocorticoid replacement
- Oral prednisone for glucocorticoid replacement, with dose increases during stress or illness
- Emergency stabilization with IV fluids and corticosteroids during an Addisonian crisis
Prognosis
Excellent long-term prognosis with appropriate lifelong hormone replacement and monitoring, though doses often need adjustment, especially during stress or illness.
This page is general reference information for educational purposes. It is not a substitute for an individual clinical assessment, current formulary guidance, or the judgment of a licensed veterinarian treating a specific patient.
Frequently asked questions
Why is Addison's disease called 'the great pretender'?
Its signs - lethargy, vomiting, poor appetite - are vague and overlap with many other conditions, and they often wax and wane, which can delay diagnosis until a more specific test is run.
Is Addison's disease in dogs a lifelong condition?
Yes, it requires lifelong hormone replacement therapy, but with consistent treatment and monitoring, most dogs live a normal, active life.