Methylprednisolone (molecular weight 374.48) is a synthetic glucocorticoid drug which is usually taken orally. It's chemical name is pregna-1,4-diene-3,20 -dione, 11,17,21-trihydroxy-6-methyl-,(6α, 11β)- and its chemical formula is C₂₂H₃₀O₅.

Like most adrenocortical steroids, methylprednisolone is typically used for its anti-inflammatory purposes. However, glucocorticoids have a wide range of effects, including changes to metabolism and immune responses. The list of medical conditions for which methlyprednisolone is rather large, and is similar to other corticosteroids such as prednisolone. Common uses includes arthritis therapy and short-term treatment of bronchial inflammation due to various respiratory diseases. It is used both in the treatment of acute periods and long-term controlling of autoimmune diseases, most notably SLE.

Methylprednisolone has serious side effects if taken long-term, including weight gain, glaucoma, osteoporosis and psychosis, especially when overdosed. The most serious side effect occurs after the kidneys cease natural production of cortisone, which methylprednisolone will replace. Abrupt cessation of the drug after this occurs can result in a condition known as Addisonian crisis, which can be fatal. To prevent this, the drug is usually prescribed with a tapering dosage, including a pre-dosed "dose pack" detailing a specific number of pills to take as designated times over a six day period.