Adrenal extracts are designed to improve the functioning of the adrenal gland, and are sometimes used for cats and dogs. Adrenal extracts are derived from the adrenal glands of bovine (beef) sources. Commercially available adrenal extracts are made using the whole gland (whole or total adrenal extracts) or just the cortex or outer portion of the gland (adrenal cortex extracts or ACE).
Whole gland adrenal extracts are available as capsules or tablets and often contain other ingredients like various vitamins, minerals and herbs.
The basic concept of "glandular therapy" is that the ingestion of glandular material of a certain animal gland will strengthen the corresponding human gland. According to this theory, adrenal glandular extracts may help the body's overworked and fatigued adrenal gland to cope better with chronic stress by regulating cortisol production. Whole adrenal extract supplements are most often used to relieve fatigue, chronic stress and reduced resistance to infection.