Methylprednisolone Injection 80 mg Multiple-Dose Vial 5 mL (RX)Methylprednisolone Injection (80 mg) Methylprednisolone is a synthetic corticosteroid (glucocorticoid) used to reduce severe inflammation and modulate the immune system. The 80 mg injection form is a potent dose typically given under medical supervision for acute or serious conditions. As noted by MedlinePlus and other sources, methylprednisolone injection is used to treat severe allergic reactions and numerous autoimmune or inflammatory disorders for