Dexamethasone is a synthetic steroid that has been used for many years in the clinical routine due to its anti-inflammatory, anti-allergic and immunosuppressive properties. Furthermore, dexamethasone has been used for a long time for prophylaxis and treatment of chemotherapy-induced nausea and vomiting. In the meantime dexamethasone has been approved as standard for the prophylaxis and treatment of postoperative nausea and vomiting (PONV). This review article outlines the indications and side effects of the perioperative administration of dexamethasone.