The purpose of this clinical trial is to determine if receiving magnesium sulfate as an adjunctive analgesic for prostate surgery is effective in reducing pain. Subjects will be randomized to receive magnesium or not receive it, as part of a standardized general anesthetic for prostate surgery. The primary objective is to demonstrate improved pain scores in patients receiving magnesium sulfate as an adjunctive analgesic during surgery. Secondary objectives include demonstrating reduced requirements for other opioids, reduced postoperative shivering, improved discharge home and adequate neuromuscular blockade reversal, measured by quantitative train of four monitoring.