"Steroids" are a family of chemicals normally made within the body. They serve as hormones —chemical signals that help to regulate the body's growth and function. Some steroid hormones, like testosterone, stimulate formation of protein and growth of muscle. Competitive athletes have been known to take illicitly derivatives of these "body-building" steroids in large amounts to improve their athletic performance. A very different group of steroid hormones are the corticosteroids, steroid hormones made in the cortex (hence, "cortico-") of the adrenal glands, which sit adjacent to the kidneys. Corticosteroid hormones have many different affects on body function, including influences on how we use our energy stores (fat, protein, and sugar) and how we adjust the salt and water content of our body.
Early in this century it was discovered that corticosteroid hormones, if purified and taken in large amounts as a medicine, have powerful anti-inflammatory effects. Ever since this discovery, corticosteroids have been used to treat a great variety of diseases where inflammation (not infection and not cancer) is the major problem—from arthritis to psoriasis to asthma. When you and your doctor talk about steroids to treat your asthma, it is these anti-inflammatory corticosteroids about which you are speaking.
Steroids Swallowed or Steroids Inhaled
To treat the inflammation of asthma within the bronchial tubes, steroids can be taken in tablet or liquid form or by inhalation. Occasionally, steroids are given by injection or—in hospitalized persons —directly into the veins (intravenous infusion). Taken as tablets, liquid, injection, or intravenous infusion, the steroid medication travels in the blood and is carried throughout the body, including to the bronchial tubes. Used in this way, steroids have their most powerful effects— both for the good (relieving asthmatic symptoms) and for the bad (undesirable side effects). On the other hand, modern steroid medications inhaled on the bronchial tubes from pressurized canisters act directly on these tubes; almost no medication is carried into the bloodstream. Although not as powerful in their immediate effects, steroids by inhalation are better suited for long-term use in the treatment of inflamed bronchial tubes because they are free of major undesirable side effects.
Examples of steroids in tablet form are prednisone (Brand name: Deltasone®) and prednisolone (Brand name: Medrol®). Examples of steroids by inhalation are triamcinolone (Brand name: Azmacort®); beclomethasone (Brand names: Vanceril®, Qvar®, and Beclovent®); flunisolide (Brand names: Aerobid® and Aerobid-M®); fluticasone (Brand name: Flovent®); and budesonide (Brand name Pulmicort®).
A Short Course of Steroids
Steroids taken in tablet or liquid form ("oral steroids") are usually prescribed for asthma that has become difficult to control by any other means; they are the most effective treatment available for a severe "attack" of asthma. Most often, they are prescribed for a short period of time: a short course may be as brief as 3-4 days or as long as 2-3 weeks. They are stopped when the asthma has gotten better and other treatments suffice to keep it under control. Longer periods of treatment and continuous treatment with oral steroids are generally avoided except for the most difficult-to-control asthma because of the undesirable side effects that often develop with prolonged oral steroid treatment