The drug is metabolized by the liver, so using it in persons with more than mild hepatic disease, especially in the presence of a CYP3A inhibitor, would have to be closely monitored; our participants will be free of hepatic, as well as renal impairment. The recommendation from the FDA is to obtain liver function tests prior to starting the drug and again should symptoms such as rash or hepatitis occur. This rather rare adverse reaction tends to occur at about one month after starting the medication (in less than 4% on the drug or placebo) , so the investigators will obtain a bilirubin and transaminases at the planned 1-month follow up.