What Do Steroids Do?
Steroids are essentially hormones and there are many different types with quite different actions. The human body makes it own steroids in the adrenal gland and these are vital for the body's normal function. Different types of synthetic steroids have been developed for use in medicine. There is a group called anabolic steroids, which some athletes take (illegally!) to help build up muscle mass, and these should not be confused with the steroids used in eczema. The other group is called catabolic steroids or glucocorticoids e.g. prednisolone); they are used as an oral medicine for a variety of different diseases because of their anti-inflammatory and immunosuppressive properties. This means that they act by damping down the activity of various immune cells that cause inflammation. Catabolic steroids have proved a very useful medicine, even lifesaving, in some medical conditions such as severe asthma or rheumatoid arthritis. The down side of this group of steroids is that if they are used at a high dose for a prolonged period they have many side-effects such as weight gain, bone thinning, decreased growth in children, high blood pressure and loss of muscle mass. Because of this, doctors try to use these at the lowest possible dose for short periods. This type of steroid is occasionally used in the treatment of a very severe flare-up of eczema. However, for the reasons already mentioned, they would normally be used for only a few weeks, starting at a high dose and then slowly decreasing. This method should prevent or minimise any serious side-effects. Fortunately, these anti-inflammatory steroids can also be made into creams for topical application - directly onto the skin. They act in a way like that of their oral counterpart, as they have been developed to try to produce the same anti-inflammatory properties without all the general ('systemic') side-effccts on the rest of the body, even after long-term use. This approach has been very successful and the topical steroids provide one of the main components in eczema treatment