Canine Addison's Disease
Addison's disease occurs when the adrenal glands (located near the kidneys) fail to produce enough hormones. The adrenal glands normally produce several hormones that control body function. For example:
- Cortisol: a hormone responsible for stress responses
- Aldosterone: a hormone responsible for balancing electrolytes (such as sodium and potassium)
It is most common in young female dogs, and you can manage it with hormone supplements.
Humans and cattle can also have this disease.
CAUSES:
The main cause of Addison's Disease is immune-mediated--the immune system attacks the adrenal glands.
Other causes include:
- Infection
- Medications
- Cancer
- Diseases of the pituitary glands
SIGNS:
Signs will be very mild at first and may even disappear for a short period, but they return more aggressively:
- Lethargy
- Loss of appetite and weight loss
- Vomiting and diarrhea
- Excessive thirst and urination
- Not reacting to stress appropriately
- Muscle weakness (wobbling when walking)
If the signs become extreme (like sudden weakness or severe vomiting and diarrhea), it becomes an Addisonian crisis and is a life-threatening emergency. Your dog may collapse in shock because it is not able to deal with stress. Go to the veterinarian right away. Your pet will have to be hospitalized and treated immediately.
DIAGNOSIS:
To properly diagnose your dog with Addison's disease, your veterinarian may perform the following:
- Review: medical history and signs of the condition
- Blood and Urine Test: Checks the heart, liver, kidneys, pancreas, metabolism, and electrolyte balance
- ACTH Stimulation Test: Tests the adrenal glands. It is the primary test used in diagnosing Addison's, and it requires at least one day of hospitalization. Your veterinarian will administer a dose of ACTH, the hormone responsible for releasing corticosteroids when a dog is under stress. A healthy animal will have elevated cortisol levels in response to ACTH, while a dog with Addison's will have none.
TREATMENT:
Treatment depends on the stage of the illness:
- If signs are severe and developed rapidly (an Addisonian crisis), your dog will require emergency treatment. This will usually include fluids through IV to fix electrolyte imbalances and balance the blood sugar levels.
- If signs are mild, your dog can get oral medication or shots to replace missing hormones. These medications will have to be increased during times of stress (such as boarding, traveling, or hospitalization).
Addison's disease treatment needs ongoing veterinary management, including monitoring hormone levels and adjusting medication.
PREVENTION:
There is no proven way to prevent Addison's disease. However, abruptly stopping steroid supplements may cause an Addisonian crisis. Therefore, if your dog is being treated for any condition with steroids, do not stop the medication abruptly.
PROGNOSIS:
Most dogs with Addison's disease that receive proper veterinary treatment live normal lives, even after an Addisonian crisis.
Medically Reviewed by Sara Ochoa, DVM
