For example, extracts of ovaries were used to supply female hormones such as progesterone. Similarly, animal adrenal
glands may contain significant levels of adrenal
hormones. This is the basis for some of the recommended uses of adrenal extracts, such as allergies, asthma, and rheumatoid arthritis (conditions that respond to cortisone). However, modern adrenal extracts are manufactured in such a way that they do not contain significant levels of adrenal hormones.