Cortisol is a hormone that is naturally produced by the adrenal glands. Cortisol is important in maintaining normal levels of sugar in the blood, and also helps regulate the balance of salts and water in the body. Corticosteroids are man-made forms of cortisol. Adverse effects seen with corticosteroid therapy are more common with higher doses and related to dose and duration of treatment. Problems with nausea and vomiting can be decreased by taking medication with food.
Corticosteroids also can decrease the effect of insulin, thereby posing problems for diabetics.
There also is a risk that the side effects associated with some vaccines may increase. Talk to your health care provider before being vaccinated if you're taking corticosteroids. Sometimes people who take high doses of corticosteroids get a more severe infection if they get measles or chickenpox, so it's good for these people to avoid those diseases if they haven't had them. You should notify your provider if you have surgery, an infection, a dental procedure, receive an injury or any kind of emergency care. Corticosteroids cannot be stopped abruptly.