Prednisone is a synthetic corticosteroid

Corticosteroid

Corticosteroids are a class of steroid hormones that are produced in the adrenal cortex. Corticosteroids are involved in a wide range of physiologic systems such as stress response, immune response and regulation of inflammation, carbohydrate metabolism, protein catabolism, blood electrolyte...

 drug that is particularly effective as an immunosuppressant

Immunosuppressive drug

Immunosuppressive drugs or immunosuppressive agents are drugs that inhibit or prevent activity of the immune system. They are used in immunosuppressive therapy to:...

 drug. It is used to treat certain inflammatory diseases and (at higher doses) some types of cancer, but has significant adverse effects. Because it suppresses the immune system, it leaves patients more susceptible to infections.

It is usually taken orally but can be delivered by intramuscular injection

Intramuscular injection

Intramuscular injection is the injection of a substance directly into a muscle. In medicine, it is one of several alternative methods for the administration of medications . It is used for particular forms of medication that are administered in small amounts...

 or intravenous injection

Intravenous therapy

Intravenous therapy or IV therapy is the infusion of liquid substances directly into a vein. The word intravenous simply means "within a vein". Therapies administered intravenously are often called specialty pharmaceuticals...

. It has a mainly glucocorticoid

Glucocorticoid

Glucocorticoids are a class of steroid hormones that bind to the glucocorticoid receptor , which is present in almost every vertebrate animal cell...

 effect.