Once general anesthesia has been induced, but prior to the first surgical incision, the first dose of the interventional agent will be administered. Repeat doses will be administered every 6 hours until 24 hours from the time that the patient enters the PACU, for a total of up to 6 doses. Once the patient has been positioned and prepped for surgery, the surgeon will infiltrate the scalp with bupivacaine 0.5% with epinephrine 1:200,000 (15-20 ml) before skin incision.