To evaluate the safety of metyrapone (MRP) for using in an outpatient study in which participants would be given 2 750 mg doses of MRP per week. Secondary study goals are to evaluate the possible efficacy of MRP as a treatment for cocaine dependence and to compare 3 factors hypothesized to induce cocaine craving: cocaine cues, stress, and cocaine itself. This study will utilize a Double Blind, placebo-controlled crossover design with 3 factors: 1) medication 2) relapse trigger and 3) infusion for an 11 day in-patient treatment.