Adrenal Insufficiency as a Complicating Factor in Allergic Dogs

CortisolMost allergies involve histamine and other chemicals which produce inflammation. Cortisol, produced by the adrenal glands, is a potent anti-inflammatory. The amount of cortisol circulating in the body is a key factor in controlling inflammation. The more histamine released by the allergic response, the more cortisol must be produced by the adrenal glands.
Adrenal insufficiency is a condition in which not enough cortisol is produced to meet the body’s requirement. The insufficiency can be produced either by a congenital defect in the adrenal glands or by chronic inflammation which exhausts the adrenal glands’ capacity to produce cortisol.
Adrenal insufficiency is possible in dogs with chronic allergies, especially if the dog does not respond to treatment. Confirmation is obtained by an ACTH stimulation test, which measures the adrenal glands’ capacity to produce cortisol. Testing is important because these dogs require long-term treatment, sometimes for life, with cortisol or other corticosteroids. Long-term treatment with corticosteroids is associated with very serious side effects; therefore, it is important to establish that treatment is necessary and will be safe.