Respiratory depression is the major concern with most of the medications (midazolam, fentanyl, propofol) currently used for MAC. There is clearly an unmet need for a sedative agent that can safely be used during MAC in both healthy and high risk populations with limited adverse side effects. A medication that can attenuate anxiety and the stress response associated with surgery and procedures without causing respiratory depression is highly desirable. A medication that reduces the total amount of opioids administered during a procedure could substantially reduce complications. Such a medication could be used either alone or in combination with other agents, thereby reducing the dose and side effects of the other agents.