Safety Study of Mibefradil When Given Four Times a Day in Healthy Volunteers

25 mg tablets for oral administration given for 7 days at a total daily dose beginning at 100 mg per day divided into four doses. Doses will be incremented in successive cohorts by 25 mg/day up to 400 mg/day.

1 out of 6 patients per cohort will receive placebo tablets identical in appearance and number to the active mibefradil arm.