Methods: Eighty patients, aged 18 to 60 years, American Society of Anesthesiologists I-II, undergoing elective gynecological surgery were enrolled. Anaesthesia was induced with propofol and fentanyl and was maintained with 60% nitrous oxide and Oxygen in sevoflurane. The magnesium group received 50 milligram/kilogram (mg/kg) Magnesium intravenous (iv) as a bolus and 15 mg/kg/hour by continuous infusion until the completion of surgery. The placebo group received the equivalent volume of isotonic saline. For intubation, 0.6 mg/kg rocuronium was administered and 0.1 mg/kg was added when Train of four (TOF) counts reached 1 or more during the procedure. At the end of the surgery at a TOF count of 1, 4 mg/kg sugammadex iv was administered. Patients were observed until a TOF ratio of 0.9 was achieved. Patient-controlled analgesia with intravenous morphine was used postoperatively.