What are corticosteroids?
Corticosteroids are a class of medications that are related to cortisone. Medications of this class reduce inflammation powerfully. They are used to reduce inflammation caused by a variety of diseases. Cortisone is one type of corticosteroid. For the purpose of this review, "cortisone" is used interchangeably with "corticosteroid." Corticosteroids can be taken by mouth, inhaled, applied to the skin, given intravenously (into a vein), or injected into the tissues of the body. Examples of corticosteroids include prednisone and prednisolone (given by mouth), Solu-Medrol (given intravenously), as well as triamcinolone, kenalog, celestone, Depo-Medrol, and others (given by injection into body tissues). This article describes the role of cortisone injections into the soft tissues and joints.
 
Is a cortisone injection merely a pain reliever or temporary remedy?
Corticosteroids are not pain relievers. They reduce inflammation. When corticosteroids relieve pain, it is because they have reduced inflammation. While the inflammation for which corticosteroids are given can recur, corticosteroid injections can provide months to years of relief when used properly. These injections also can cure diseases (permanently resolve them) when the problem is tissue inflammation localized to a small area, such as bursitis and tendonitis.
 
For what conditions are cortisone injections used?
Cortisone injections can be used to treat the inflammation of small areas of the body (local injections), or they can be used to treat inflammation that is widespread throughout the body (systemic injections). Examples of conditions for which local cortisone injections are used include inflammation of a bursa (bursitis), a tendon (tendonitis), and a joint (arthritis). Systemic corticosteroid injections are used for conditions such as allergic reactions, asthma, and rheumatoid arthritis affecting many joints.
 
What are the advantages of cortisone injections?
Cortisone injections can be administered easily in the doctor's office. Other advantages include the rapid onset of the medication's action, dependability, and minimal side effects. Another distinct benefit of a corticosteroid injection is that the relief of localized inflammation in a particular body area is more rapid and powerful than with traditional antiinflammatory medications given by mouth such as aspirin. A single injection also can avoid certain side effects, notably irritation of the stomach, that accompany many oral antiinflammatory medications.
 
What are the disadvantages and side effects of cortisone injections?
Disadvantages of cortisone injections are the necessity of piercing the skin with a needle as well as potential short- and long-term side effects. It should be emphasized that though each of these side effects is possible, they usually do not occur. Short-term side effects are uncommon but include shrinkage (atrophy) and lightening of the color (depigmentation) of the skin at the injection site, introduction of bacterial infection into the body, local bleeding from broken blood vessels in the skin or muscle, soreness at the injection site, and aggravation of inflammation in the area injected because of reactions to the corticosteroid medication (postinjection flare). Tendons can be weakened by corticosteroid injections in or near tendons. Tendon ruptures as a result have been reported. In people who have diabetes, cortisone injections can elevate the blood sugar. In patients with underlying infections, cortisone injections can suppress somewhat the body's ability to fight the infection and possibly worsen the infection or may mask the infection by suppressing the symptoms and signs of inflammation. Generally, cortisone injections are used with caution in people with diabetes and avoided in people with active infections. Cortisone injections are used cautiously in people with blood-clotting disorders. Long-term side effects of corticosteroid injections depend on the dose and frequency of the injections. With higher doses and frequent administration, potential side effects include thinning of the skin, easy bruising, weight gain, puffiness of the face, elevation of blood pressure, cataract formation, thinning of the bones (osteoporosis), and a rare but serious damage to the bones of the large joints (avascular necrosis).