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Aims: Functional magnetic resonance imaging research has attempted to elucidate the neurobehavioral underpinnings of cocaine dependence by evaluating differences in brain activation to cocaine and response inhibition cues between cocaine-dependent individuals and controls. This study investigated associations between task-related brain activation and cocaine use characteristics., Design: Cross-sectional., Setting: The Center for Biomedical Imaging at the Medical University of South Carolina, USA., Participants: Fifty-one cocaine users (41 dependent)., Measurements: Brain activation to cocaine-cue exposure and Go No-Go tasks in six a priori selected brain regions of interest and cocaine use characteristics (i.e. cocaine dependence status, years of cocaine use, cocaine use in the past 90 days) assessed via standardized interviews., Findings: Participants demonstrated elevated activation to cocaine (bilateral ventral striatum, dorsal caudate, amygdala) and response inhibition (bilateral anterior cingulate, insula, inferior frontal gyrus) cues in all hypothesized brain regions. Years of cocaine use was associated with task-related brain activation, with more years of cocaine use associated with greater activation to cocaine cues in right (F = 7.97, P = 0.01) and left (F = 5.47, P = 0.02) ventral striatum and greater activation to response inhibition cues in left insula (F = 5.10, P = 0.03) and inferior frontal gyrus (F = 4.12, P = 0.05) controlling for age, cocaine dependence status and cocaine use in the past 90 days., Conclusions: Years of cocaine use may be more centrally related to cocaine cue and response inhibition brain activation than cocaine dependence diagnosis or amount of recent use., (© 2014 Society for the Study of Addiction.)

Motivation to change is believed to be a key factor in therapeutic success in substance use disorders; however, the neurobiological mechanisms through which motivation to change impacts decreased substance use remain unclear. Existing research is conflicting, with some investigations supporting decreased and others reporting increased frontal activation to drug cues in individuals seeking treatment for substance use disorders. The present study investigated the relationship between motivation to change cocaine use and cue-elicited brain activity in cocaine-dependent individuals using two conceptualizations of 'motivation to change': (1) current treatment status (i.e. currently receiving versus not receiving outpatient treatment for cocaine dependence) and (2) self-reported motivation to change substance use, using the Stages of Change Readiness and Treatment Eagerness Scale. Thirty-eight cocaine-dependent individuals (14 currently in treatment) completed a diagnostic assessment and an fMRI cocaine cue-reactivity task. Whole-brain analyses demonstrated that both treatment-seeking and motivated participants had lower activation to cocaine cues in a wide variety of brain regions in the frontal, occipital, temporal and cingulate cortices relative to non-treatment-seeking and less motivated participants. Future research is needed to explain the mechanism by which treatment and/or motivation impacts neural cue reactivity, as such work could potentially aid in the development of more effective therapeutic techniques for substance-dependent patients., (© 2012 The Authors, Addiction Biology © 2012 Society for the Study of Addiction.)

Background: The development of addiction is marked by a pathological associative learning process that imbues incentive salience to stimuli associated with drug use. Recent efforts to treat addiction have targeted this learning process using cue exposure therapy augmented with d-cycloserine (DCS), a glutamatergic agent hypothesized to enhance extinction learning. To better understand the impact of DCS-facilitated extinction on neural reactivity to drug cues, the present study reports fMRI findings from a randomized, double-blind, placebo-controlled trial of DCS-facilitated cue exposure for cocaine dependence., Methods: Twenty-five participants completed two MRI sessions (before and after intervention), with a cocaine-cue reactivity fMRI task. The intervention consisted of 50mg of DCS or placebo, combined with two sessions of cocaine cue exposure and skills training., Results: Participants demonstrated cocaine cue activation in a variety of brain regions at baseline. From the pre- to post-study scan, participants experienced decreased activation to cues in a number of regions (e.g., accumbens, caudate, frontal poles). Unexpectedly, placebo participants experienced decreases in activation to cues in the left angular and middle temporal gyri and the lateral occipital cortex, while DCS participants did not., Conclusions: Three trials of DCS-facilitated cue exposure therapy for cocaine dependence have found that DCS either increases or does not significantly impact response to cocaine cues. The present study adds to this literature by demonstrating that DCS may prevent extinction to cocaine cues in temporal and occipital brain regions. Although consistent with past research, results from the present study should be considered preliminary until replicated in larger samples., (Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.)

Objective: Animal models suggest that N-acetylcysteine inhibits cocaine-seeking. The present pilot study evaluated whether N-acetylcysteine would suppress reactivity to cocaine-related cues in cocaine-dependent humans., Method: In this double-blind, placebo-controlled trial, 15 participants received N-acetylcysteine or placebo during a 3-day hospitalization. Participants were crossed over to receive the opposite condition on a second, identical 3-day stay occurring 4 days later. During each hospital stay, participants completed a cue-reactivity procedure that involved collecting psychophysical and subjective data in response to slides depicting cocaine and cocaine use., Results: While taking N-acetylcysteine, participants reported less desire to use and less interest in response to cocaine slides and watched cocaine slides for less time., Conclusions: The inhibition of cocaine cue reactivity is consistent with existing preclinical data and supports the use of N-acetylcysteine as a treatment for cocaine dependence.

A double-blind placebo-controlled crossover Phase I trial was conducted to assess the safety and tolerability of N-Acetylcysteine (NAC) in healthy, cocaine-dependent humans. Thirteen participants attended a three-day hospitalization in which they received placebo or NAC. Subjects were crossed over to receive the opposite medication condition during a second three-day hospitalization, which occurred the following week. Across placebo and NAC conditions, only mild side effects were noted, and the number of subjects reporting side effects did not differ. There were trends for a greater reduction in withdrawal symptoms and craving within the NAC condition. These preliminary results suggest that NAC is well tolerated in healthy, cocaine-dependent individuals and may reduce cocaine-related withdrawal symptoms and craving.

To explore the concordance between urine drug screen (UDS) results and self-report of cocaine use, results in a pharmacologic treatment trial for cocaine dependence were evaluated. Subjects with at least two occurrences of a positive UDS for cocaine were characterized as either an under-reporter (UR, n = 43) or a truthful reporter (TR, n = 32). Interestingly, URs attended more study sessions and were more likely to complete the study. Significant differences were found in cocaine use patterns and the prevalence of Axis I and Axis II disorders. This information may be important in guiding the judicious use of UDS in clinical and research settings.

The current pilot project was designed to evaluate the safety and tolerability of a loading dose of divalproex (DVPX) in subjects with cocaine dependence. Seventeen cocaine-dependent subjects were enrolled in an eight-week, open-label trial of 20 mg/kg/day DVPX. Subjects were seen weekly and urine drug screens were obtained at each visit. Over the eight-week trial, craving intensity and frequency as well as reported time using cocaine decreased significantly. Retention in the current study was 79% at week four and 50% at week eight. The medication and dosing strategy was well tolerated. This pilot study indicates that DVPX loading is well tolerated and may be efficacious in the treatment of cocaine dependence. A placebo-controlled trial would be of interest.

Background: Although multiple medications have been studied for the treatment of cocaine dependence, no medication has been shown to have a robust effect on craving and use. This pilot project was designed to evaluate the safety and tolerability of gabapentin in subjects with cocaine dependence., Method: Thirty cocaine-dependent subjects (DSM-IV criteria) were enrolled in an 8-week, open-label trial of 1,200 mg/day of gabapentin in divided doses. Urine drug screens, subjective measures of craving, and cocaine use interviews were conducted at each weekly visit., Results: Baseline rating of amount and frequency of craving decreased significantly by week 8 (78% vs. 25% for amount, p = .000; 74% vs. 23% for frequency, p = .004). Positive urine drug screens for cocaine decreased from 86% at baseline to 29% at weeks 4 and 8. There were no reports of significant side effects or adverse events., Conclusion: This pilot study indicates that gabapentin is safe and well tolerated and may be beneficial in the treatment of cocaine dependence. A placebo-controlled trial would be of interest.

Priapism is a urologic disorder and medical emergency with a variety of known etiologies including the use of psychotropic medications. The antidepressant trazodone is the agent most frequently implicated in the precipitation of priapism. Additionally, a number of drugs of abuse including marijuana, ethanol, and cocaine have been known to cause the disorder. It is unknown if drugs may act in an additive or a synergistic manner to cause priapism. We report a case of priapism which occurred following trazodone overdose in an individual actively using cocaine. This case suggests that combined trazodone and cocaine use may pose an additional risk of priapism. Since trazodone is commonly employed as a hypnotic and often chosen for polysubstance abusers due to its low abuse potential, clinicians should be aware of the possible additive risk of priapism in this patient population.