Patients who are taking strong CYP3A4 inducers or inhibitors such as clarithromycin, itraconazole, ketoconazole, nefazodone, telithromycin, rifampin, rifabutin, rifampacin, or St. John's Wort must discontinue the medication beginning at least one week prior to surgery and lasting for the duration of the study. The only exception will be dexamethasone which can be used post-operatively as indicated.