View clinical trials related to Methamphetamine Abuse.
Filter by:While deficits in dopamine D2-type receptor availability have been linked to substance use disorders, higher availability associates with better behavioral treatment outcomes for stimulant dependence and resilience to addiction. Varenicline has been shown to upregulate D2-type receptors in drug-naive rats, and could be a useful therapeutic approach for the treatment of addictive disorders in humans. The purpose of the study is to assess the relationship between varenicline, dopamine signaling (specifically, D2-type receptor availability), functional connectivity within corticostriatal circuitry, genetic markers associated with smoking and methamphetamine abuse, and measures of cognitive performance. The investigators hypothesize that varenicline but not placebo will upregulate (increase) striatal dopamine D2-type receptor availability and improve cognition, and that the change in availability will correlate with the change in cognition. The investigators also hypothesize that varenicline but not placebo treatment will repair dysregulated connectivity between the striatum and prefrontal cortex observed in methamphetamine users, and will correlate with the change in cognition. The study design consists of two positron emission tomography (PET) and functional magnetic resonance imaging (fMRI) scans to measure dopamine D2-type receptor availability and functional connectivity between the prefrontal cortex and striatum, two cognitive testing sessions including a battery of tests assessing working memory, declarative memory, sustained attention, inhibitory control, and reward-based decision making. Following eligibility screening, thirty six methamphetamine users will be enrolled and tested/scanned once prior to initiation of varenicline or placebo treatment and then again after completion of treatment.
This is a study of 4 nontreatment seeking individuals who were MA-dependent and the safety and tolerability of atomoxetine. This double-blind, placebo-controlled, within-subjects study is to determine the safety and tolerability of atomoxetine. MA abusing participants will undergo a 1-day outpatient screening and if it is safe for the participants to proceed with the study they will participate in two inpatient components of the study that will occur in the University of California Los Angeles (UCLA) General Clinical Research Center (GCRC). The first inpatient stay will be 15 days, and the second will be a 9 days stay that includes drug administration and assessments. There will be at least a two week interval between inpatient components. During the inpatient components participants will receive alternating study drugs; atomoxetine or placebo and four sessions of IV MA administration or saline.