Non-Treatment Study of Factors Affecting Cocaine Drug Choice

Outpatient Phase: Participants will be outpatients and must come to the Jefferson Avenue Research Program three times a week (Mon-Wed-Fri). This phase will last two weeks. At each visit participants will be asked to provide a urine sample and to complete questionnaires that ask about substance use. Inpatient Phase: Participants will live on an inpatient research unit at least 2 consecutive nights and possibly up to 20 consecutive nights. Participants cannot have visitors and will not be allowed to leave the inpatient unit (except with a staff escort) unless they drop out of the study. We will collect daily urine samples to make sure participants are not using any drugs except those in the study. Participants will take part in multiple trials (up to 11 experimental sessions) where they will be given a standard amount of powder (identified as Drug A or Drug B) to inhale through a straw into their nose. The powder will contain placebo (a powder containing no drug) or different doses of cocaine. We will measure how participants are feeling using questionnaires and we will record vital signs-including breathing rate, blood oxygen level, heart rate, and blood pressure. Participants will also be asked to perform a 3-hour computer task that allows them to work for Drug A, Drug B, or money. At the end of the computer task participants will receive the amount of drug they earned and a receipt for the amount of money they earned. To complete the study, a minimum stay of 16 inpatient nights is required. The maximum stay is 20 inpatient nights.