Of the medications available in the arsenal of anti-inflammatory therapies, there is one type that has caused considerable debate. This is the class of drugs known as corticosteroids.
Present naturally to some degree in all animals, corticosteroids are normally produced by the adrenal glands. Their natural actions protect the body against a variety of internal and environmental stressors, and they help the animal adapt to changes in its environment for improved survival. As medications, steroids have diverse effects, some of which are beneficial in the short term, yet longer use might exert less desirable results. When used judiciously and appropriately, corticosteroid medications can be of great benefit to limit many disease processes in the horse. When used unwisely, they can injure or kill.
What are Corticosteroids?
Corticosteroids, commonly referred to as "steroids," occur in different forms with various physiologic actions. The glucocorticoids most notably affect the metabolism of carbohydrate, fat, and protein, while also possessing distinctive anti-inflammatory properties. Another class of corticosteroids, the mineralocorticoids, control water and sodium retention by the kidneys.
The adrenal glands generate a third group of corticosteroids, the sex hormones. Anabolic steroids are derivatives of the sex hormone testosterone, and they are recognized for their ability to promote body growth, protein synthesis, and increased muscle mass.
This discussion will focus only on synthetically produced glucocorticoid drugs because of their potent use in targeting inflammation and their extensive use in horses.