Changes in ovarian hormones across the menstrual cycle impact responses to cocaine in women. Studies have shown that cocaine's effects are dampened during the luteal phase of the menstrual cycle, when estrogen and progesterone concentrations are high, relative to the other phases of the cycle, when concentrations of these hormones are relatively low. The purpose of this study is to determine whether progesterone reduces subjective and physiological responses to cocaine in cocaine dependent individuals. In addition, this study will help to advance the possibility of hormonal progesterone and pharmacologically-related drugs as potential treatment components for cocaine abuse.~Participants will undergo two 4-day inpatient periods, totaling 8 days of treatment. For women, the inpatient periods will occur during two consecutive menstrual cycles; for men, these will occur during two consecutive months. On Day 1, participants will receive a first dose of either progesterone or placebo. On Day 2, participants will receive a second and third dose of study medication. Participants will also participate in an adaptation session, which will familiarize the participant with the smoking equipment that will be used the following day. On Day 3, participants will receive a fourth dose of medication 2 hours prior to a smoking lab session. Prior to beginning the smoking lab session, participants will be asked to rate their current cocaine craving, anxiety level, appetite, and premenstrual symptoms. Participants will then be given a sample of the cocaine dose for the given day. During the smoking lab session, participants will be asked additional cocaine craving questions at pre-determined intervals and will be given the option to trade in previously earned tokens for either money or a dose of cocaine. Following completion of the smoking lab session, participants will receive their fifth dose of medication.
Past research has demonstrated that cocaine dependent women experience less severe responses to cocaine during the luteal phase of the menstrual cycle, when estrogen and progesterone concentrations are high. The purpose of this study is to determine whether administered progesterone reduces subjective and physiological responses to cocaine in cocaine dependent individuals.