- Started or changed within 60 days prior to the screening visit the dosage of any drug (including OTC) that affects cognitive function, such as neuroleptics, antidepressants, anxiolytics, sedatives, hypnotics, anti-convulsants, centrally acting antihypertensive agents such as clonidine and Aldomet; or other medications that have been shown to have possible effects on cognition such as Vitamin E, nonsteroidal anti-inflammatory drugs, and statins, or if, in the Investigator's opinion, the dosage of such medication is likely to be changed during the course of this trial. Any changes in the dosage of any of these drugs during the course of the trial and the reason for the change must be fully recorded in the concomitant medication page of the patient's case report form (CRF). If a drug that affects cognition (e.g., a hypnotic or anxiolytic drug) is given on a PRN basis, such treatment should be interrupted for 12 hours before a visit, if possible;