Cortisone is a type of steroid that is produced naturally by the adrenal gland. It is usually released by this gland when the body is under stress. Injectable cortisone is synthetically produced. I use a brand called Celestone because it is soluble and has less chance of causing depigmentation secondary to fat necrosis after an injection. Cortisone acts as a powerful anti-inflammatory medication. It is injected at the site of inflammation and tenderness. Usually the injections work within several days subsequent to the injection and can take as long as 3 weeks to see the full effects. Some of the adverse side effects include a temporary flare, i.e. inflammation from the shot itself and this is unusual and can be treated with local ice packs. In addition, if the patient is a diabetic, sometimes there can be a transient increase of blood sugar secondary to the injection. Despite the possible side effects, which are minimal, cortisone injections are usually very effective in treating inflammatory conditions such as trigger fingers and /or tennis elbow and/or tendinitis. It could occasionally also be injected around the carpal tunnel in an effort to decrease the inflammation around the median nerve.