Hypoadrenocorticism, often called Addison’s disease, is the result of inadequate cortisol production by the adrenal glands. This can be a deficiency of mineralocorticoids which regulate electrolytes, glucocorticoids which are involved in glucose metabolism or both. It is most commonly seen in dogs and is rare in cats. It usually occurs between one to seven years of age and is more common in Standard Poodles, Labrador Retrievers, and Portuguese Water Spaniels, although it can occur in any breed.

The most common signs are depression, lethargy, loss of appetite, weakness, vomiting, diarrhea, weight loss, shaking or shivering, and increased thirst and urine output. Symptoms can often be vague and laboratory test results are often equivocal, making diagnosis difficult.

Treatment involves replacing mineralocorticoids with DOCP, an injection given every 25 – 28 days and low doses of oral prednisone. Patients are treated indefinitely and generally do well, provided treatment schedules are followed and electrolytes and renal function are monitored frequently.