Corticosteroids are medicines that are similar to the natural hormone cortisone and belong to the family of drugs called steroids. Corticosteroids are used in several forms, to treat many different conditions. Because they reduce itching, swelling, redness, and allergic reactions, they are often used in treating skin problems, severe allergies, asthma, and arthritis. These drugs also suppress the body's immune response, so they are used in patients who have received organ transplants, to reduce the chance of rejection. In people whose bodies do not produce enough natural corticosteroids, the drugs can raise the levels of those hormones. Corticosteroids also are used to treat certain cancers (along with other drugs), and to reduce inflammation in other medical conditions.

Examples include inhalant corticosteroids that are used to prevent asthma attacks, and corticosteroid ointments, creams and gels that are used to treat skin problems. Common varieties include beclomethasone (Beconase, Vancenase, Vanceril), betamethasone (Diprolene, Lotrisone), hydrocortisone, mometasone (Elocon), prednisone (Deltasone, Orasone), and triamcinolone (Azmacort, Nasacort).

They affect many body processes, including the breakdown of protein, fat, and carbohydrate; the activity of the nervous system; the balance of salt and water; and the regulation of blood pressure. Because of their widespread effects, these drugs are useful in treating many medical conditions, but they can also have serious side-effects.

Side-effects
Side effects are generally rare when corticosteroids are used for a short time. However, prolonged use may lower the body's ability to fight off infections or may make infections harder to treat. Other common side effects include changes in appetite (increase or decrease), nervousness, restlessness, sleep problems, and indigestion. These problems usually go away as the body adjusts to the drug and do not require medical treatment.

Less common side-effects may occur with some forms of corticosteroids. Inhalants may cause dry throat, headache, nausea, skin bruising or thinning, and an unpleasant taste. Nasal spray forms may irritate the nose or throat, and ointments, gels, or creams may irritate the skin. Again, these side-effects do not need medical attention unless they don't go away or they interfere with normal activities.

More serious side-effects are not common, but may occur. If breathing problems, wheezing, or tightness in the chest occur, call a physician immediately. Additional side-effects do not need emergency care, but should have prompt medical attention. Anyone who is taking corticosteroids and has any of the symptoms listed below should check with the physician who prescribed the medicine as soon as possible:

• White, curd-like patches in the mouth or throat
• Pain when swallowing or eating
• White patches or sores inside nose or in the anal area
• Eye pain or vision problems
• Loss of sense of taste or smell
• Stomach or abdominal pains, nausea, or vomiting
• Rash, acne, or other skin problems
• Swelling of face, eyelids, or lips
• Unusual tiredness or weakness
• Stuffy, dry, or runny nose (continuing over time)
• Watery eyes (continuing over time)
• Black, tarry stools
• Irregular heartbeat
• Menstrual problems
• Muscle cramps, weakness, or pain
• Rapid weight gain
• Unusual marks or bruises
• Wounds that won't heal
• Confusion, excitement, restlessness, mood swings, or unusual or disturbing thoughts or feelings
• Hallucinations.

• Allergies: Anyone who has had unusual reactions to corticosteroids in the past should let his or her physician know before taking the drugs again. The physician should also be told about any allergies to foods, dyes, preservatives, or other substances.
• Pregnancy: Too much use of corticosteroids during pregnancy may cause problems in the baby after it is born, such as slower growth. Nasal and inhalant forms of the drugs are considered safer to use in pregnancy than are corticosteroids taken by mouth or injection. When used properly, corticosteroid ointments, creams, and gels -- used to treat skin conditions -- are not known to cause any problems if used during pregnancy.
• Breastfeeding: The safety of using corticosteroids while breastfeeding depends on the type of corticosteroid and the form in which it is being used. When taken by mouth or injection, for example, the drugs pass into breast milk and may cause growth problems in nursing babies. Creams, gels, and other forms that are applied to the skin are not known to cause problems in nursing babies whose mothers use them. However, these medicines should not be applied to the breasts just before breastfeeding. In general, women who are breastfeeding should ask their physicians before using any type of corticosteroid.
• Diabetes: Corticosteroids may affect blood sugar levels. Any person with diabetes who notices changes in blood or urine test results while taking corticosteroids should check with a physician.
• Other medical conditions: Before using corticosteroids, people with any of the following medical problems should make sure their physicians are aware: Osteoporosis or any other bone disease; Current or past tuberculosis; Glaucoma or cataracts; Infections of any type (virus, bacteria, fungus, amoeba); Sores in the nose or recent nose surgery (if using nasal spray forms of corticosteroids); Underactive or overactive thyroid; Liver disease; Stomach or intestine problems; Heart disease; High blood pressure; High cholesterol; Kidney disease or kidney stones; Myasthenia gravis; Systemic lupus erythematosus (SLE); Emotional problems; Skin conditions that cause the skin to be thinner to bruise more easily.
• Use of certain medicines: Taking corticosteroids with certain other drugs may affect the way the drugs work or may increase the chance of side-effects.