Crack Cocaine Dependence Research Articles

Cannabidiol for the treatment of crack-cocaine craving: an exploratory double-blind study.

Objective:To assess the efficacy of cannabidiol (CBD) in the management of crack-cocaine craving and the treatment of frequent withdrawal symptoms.Methods:Thirty-one men with a diagnosis of crack-cocaine dependence were enrolled in a randomized, double-blind, placebo-controlled trial. We applied neuropsychological tests and assessed craving intensity, anxiety and depression symptoms, and substance use patterns at baseline and at the end of the trial. The participants were treated with CBD 300 mg/day or placebo for 10 days. During this period, we used a technique to induce craving and assessed the intensity of symptoms before and after the induction procedure.Results:Craving levels reduced significantly over the 10 days of the trial, although no differences were found between the CBD and placebo groups. Craving induction was successful in both groups, with no significant differences between them. Indicators of anxiety, depression, and sleep alterations before and after treatment also did not differ across groups.Conclusion:Under the conditions of this trial, CBD was unable to interfere with symptoms of crack-cocaine withdrawal. Further studies with larger outpatient samples involving different doses and treatment periods would be desirable and timely to elucidate the potential of CBD to induce reductions in crack-cocaine self-administration.

ASSESSMENT OF FRACTAL DIMENSION AND PANORAMIC RADIOMORPHOMETRIC INDICES IN CRACK–COCAINE-ADDICTED MEN: A CROSS-SECTIONAL STUDY

The impact of crack–cocaine dependence on the quality and microarchitecture of the mandibular bone tissue requires further investigation. This cross-sectional study evaluated the fractal dimension and panoramic radiomorphometric indices in crack–cocaine-addicted men. Panoramic radiographs were obtained from 24 addicted and 24 nonaddicted men (control individuals) between the ages of 18 years and 60 years. The fractal dimensions of four different regions, along with the cortical mandibular, mental, and panoramic mandibular indices, were evaluated bilaterally. Significance level of 5% ([Formula: see text]) was adopted in the statistical analysis. Mean fractal dimension value of all the four different regions of the jaw in the addict group ([Formula: see text]) was lower than that of the nonaddict group ([Formula: see text]; [Formula: see text]). Furthermore, the inter-group panoramic radiomorphometric indices were not significantly different ([Formula: see text]). Mean fractal dimension value was associated with the duration of addiction ([Formula: see text]; [Formula: see text]), contrary to the indices ([Formula: see text]). Crack–cocaine addiction and longer duration of addiction were associated with lower fractal dimension values in the mandibular bone. Therefore, patients and dentists should be aware of this condition while planning periodontal, implant, and orthodontic therapies. Furthermore, crack–cocaine patients should be referred to a specialist for the evaluation of osteoporosis and osteopenia.

Concurrent Use of Alcohol and Crack Cocaine is Associated with High Levels of Anger and Liability to Aggression

Objective: To evaluate aggressiveness in individuals receiving treatment for alcohol and crack cocaine use, both alone and in combination with one another, in order to compare them to control subjects with no history of drug problems, using the State-Trait Anger Expression Inventory. Method: The sample consisted of 67 men aged 18-65 years, divided into four groups: alcohol (n = 13); crack cocaine (n = 25); crack cocaine + alcohol (n = 16) and controls (n = 13). Participants completed the following instruments: socioeconomic questionnaire, the Wechsler Abbreviated Scale of Intelligence and the State-Trait Anger Expression Inventory. Results: Individuals with alcohol dependence alone, or comorbid with crack cocaine dependence, showed elevated levels of aggression and anger, though these varied according to the drug of abuse. Concurrent users of alcohol and crack cocaine had the highest levels of aggression, followed by isolated alcohol users, suggesting an association between alcohol consumption and aggression. Conclusion: The present findings suggest that alcohol and aggression levels may be associated with violent behavior. Concurrent use of alcohol and crack cocaine was related to higher levels of aggression, which may be associated with more severe alterations in behavior and impulse control.

Modulation of neuropeptide Y levels is impaired in crack withdrawal patients.

Introduction The dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis has a key role in drug addiction susceptibility. In addition to the well-known relationship between cortisol and the HPA axis, other molecules are involved with stress response and could modify the HPA activation, such as the neuropeptide Y (NPY), which has anxiolytic proprieties. There are few studies evaluating the effect of NPY levels on addiction, especially in crack cocaine dependence. Objective To evaluate NPY in crack users during early withdrawal to determine its relationship with drug use and cortisol levels. Methods We analyzed 25 male inpatient crack users. Serum NPY levels were measured at admission and discharge (mean of 24 days). Morning salivary cortisol was measured at admission. Results Serum NPY levels at admission and discharge were very similar. Lower NPY levels at discharge were associated with higher lifetime crack use. Also, a negative correlation was found between morning cortisol and delta NPY (NPY discharge - NPY admission). Conclusion These preliminary findings indicate that crack use influences the modulation of NPY levels and modifies stress response. The NPY pathway may play an important role in the pathophysiology of crack addiction, and the anxiolytic effect of NPY may be impaired in crack users. Future studies should consider NPY as a measurable indicator of the biological state in addiction.

Adulterants in crack cocaine in Brazil.

Brazil is the world's biggest consumer of crack cocaine, and dependence is a major public health issue. This is the first study to investigate the prevalence of potentially harmful adulterants present in hair samples from Brazilian patients with crack cocaine dependence. We evaluated adulterants in hair samples extracted by convenience from 100 patients admitted at the 48 hour-observation unit of Centro de Referência de Álcool, Tabaco e Outras Drogas (CRATOD), Brazil's largest center for addiction treatment. A cross-sectional analysis was performed with the data obtained. Adulterants were found in 97% of the analyzed hair samples. The most prevalent adulterant was lidocaine (92%), followed by phenacetin (69%) and levamisole (31%). Adulterants were widely prevalent in hair samples from crack users treated at CRATOD: at least one adulterant was present in virtually all the hair samples collected. This points to a need to monitor adverse effects in the clinical setting in order to provide this high-risk group of patients with prompt and effective care related to the acute and chronic complications associated with these adulterants.

M113 - INFLUENCE OF NICOTINIC RECEPTOR GENE – CHRNA5 – ON CRACK COCAINE DEPENDENCE AND SEVERITY

Background Crack cocaine is a highly addictive substance and this dependence has a significant prevalence worldwide, especially in Brazil. Several factors are involved on crack cocaine dependence, and heritability estimates have highlighted the influence of genetic variants in the dependence susceptibility. Previous studies have shown that genetic variants in nicotine receptor genes are not only associated with nicotine abuse, but also with cocaine dependence. Our aim was to investigate the effects of polymorphisms in the nicotinic receptor alpha 5 gene - CHRNA5 - on crack cocaine dependence. Methods Three hundred crack cocaine users and six hundred and thirty-three healthy controls were enrolled in this study. The sample was composed of white Brazilians with European descent. Diagnoses and clinical assessments were performed according to DSM-IV criteria. The Addiction Severity Index - 6 (ASI-6) was used to assess the severity of dependence. Three polymorphisms were analyzed in the CHRNA5 gene (rs588765, rs16969968, and rs514743). Logistic regression models and general linear models were used to evaluated the effect of SNPs on crack cocaine addiction and severity of dependence, respectively. Results Significant effects were found for two polymorphisms. Genotypes TT-rs588765 and AA-rs16969968 were associated with reduced risk to crack cocaine dependence (OR=0.581, P=0.037; OR=0.532, P=0.009, respectively). However, only a trend towards association for rs514743 was detected (TT, OR=0.571, P=0.065). Analyses regarding severity of dependence did not reveal any significant association between SNPs and scores generated by ASI-6. Discussion We replicated previous findings regarding the influence of CHRNA5 gene on cocaine addiction. Notwithstanding, studies have demonstrated that rs16969968 apparently presents opposite effects in nicotine and crack/cocaine addictions. Our perspectives include increasing sample size and further explore other aspects possibly involved with addiction, such as age of first use and psychiatric comorbidities. Potential implications of these genetic factors should be more explored in future studies.

Insights into the Effects of Crack Abuse on the Human Metabolome Using a NMR Approach.

Approximately 255 million people consume illicit drugs every year, among which 18 million use cocaine. A portion of this drug is represented by crack, but it is difficult to estimate the number of users since most are marginalized. However, there are no recognized efficacious pharmacotherapies for crack-cocaine dependence. Inflammation and infection in cocaine users may be due to behavior adopted in conjunction with drug-related changes in the brain. To understand the metabolic changes associated with the drug abuse disorder and identify biomarkers, we performed a 1H NMR-based metabonomic analysis of 44 crack users' and 44 healthy volunteers' blood serum. The LDA model achieved 98% of accuracy. From the water suppressed 1H NMR spectra analyses, it was observed that the relative concentration of lactate was higher in the crack group, while long chain fatty acid acylated carnitines were decreased, which was associated with their nutritional behavior. Analyses of the aromatic region of CPMG 1H NMR spectra demonstrated histidine and tyrosine levels increased in the blood serum of crack users. The reduction of carnitine and acylcarnitines and the accumulation of histidine in the serum of the crack users suggest that histamine biosynthesis is compromised. The tyrosine level points to altered dopamine concentration.

Is Ayahuasca an Option for the Treatment of Crack Cocaine Dependence?

ABSTRACTThe low efficacy of crack cocaine addiction treatment available in Brazil has led Brazilian users to find alternatives to reduce drug consumption or even to reach abstinence. One of them is the use of entheogenic substances, like ayahuasca, an infusion obtained from two native plant species from the Amazon. The present report aimed to understand how crack cocaine users recover from drug addiction by consuming ayahuasca tea in a religious context. This is a qualitative study with a purposeful sample of 40 crack cocaine users, based on in-depth, semi-structured interviews. Participants reported that ayahuasca allowed them to access a consciousness dimension which enabled them to solve problems and traumas and reduce crack cocaine consumption. The religious ceremony increased the user’s spirituality and the reception from the community gave them a sense of self-esteem, strengthening them in an emotional and social way. That positive experience has been incorporated into the daily routine of most participants. Findings indicate that ayahuasca, in a religious context, may have therapeutic value for crack cocaine dependence treatment.

Crack cocaine users views regarding treatment with contingency management in Brazil

BackgroundContingency management (CM) has recently shown efficacy in promoting abstinence and retention in treatment among crack cocaine users in Brazil. However, partially because of unawareness and resistance among health care providers, CM has not been widely employed. The objective of this study was to conduct a secondary analysis in order to evaluate how CM participants perceive their treatment experience.MethodsTwenty-seven crack cocaine users, previously assigned to 12 weeks of CM treatment, were assessed with a structured questionnaire designed to assess their personal opinion of, difficulty in understanding, and acceptance of the CM intervention, as well as their opinion regarding its impact on their treatment responses.ResultsDescriptive analyses showed that 92.6% of the participants found it very easy to understand the CM protocol. All participants reported liking their CM experience quite a bit. For the perceived effects of CM on their treatment response, 81.5% of the participants stated that CM helped them considerably, the mean score for the impact of CM on treatment response (out of a maximum of 10) being 9 (SD = 1.5). When asked if they believed CM could help other people with crack cocaine dependence, 92.6% of the participants stated that CM could help such people a lot and 7.4% stated that it could help them a little.ConclusionsFrom the perspective of the patients, CM was easily assimilated, easily accepted, and had a direct positive effect on treatment response. These findings provide additional support for the incorporation of CM into substance abuse treatment services in Brazil.

Attention and memory deficits in crack-cocaine users persist over four weeks of abstinence

BackgroundCrack-cocaine addiction is an important public health problem worldwide. Although there is not a consensus, preliminary evidence has suggested that cognitive impairments in patients with crack-cocaine dependence persist during abstinence, affecting different neuropsychological domains. However, few studies have prospectively evaluated those deficits in different phases of abstinence. ObjectivesThe main aim of present study was to examine neuropsychological performance of patients with crack-cocaine dependence during early abstinence and after four weeks, comparing with matched controls. MethodsThirty-five males with crack-cocaine dependence, aged 18 to 50years, who met DSM-IV criteria for cocaine dependence and a control group of 33 healthy men were enrolled. They were assessed through Block Design, Digit Span and Vocabulary of Wechsler Adult Intelligence Scale (WAIS-III), the Rey Auditory Learning Test (RAVLT) and the Verbal Fluency (FAS) between 3 and 10days (mean of 6.1±2.0days) and after 4weeks of abstinence. ResultsCompared to controls, the crack-cocaine dependent group exhibited deficits in cognitive performance affecting attention, verbal memory and learning tasks in early withdrawal. Most of the cognitive deficits persisted after four weeks of abstinence. ConclusionPresent results observed that the group of patients with crack-cocaine dependence presented persistent deficits affecting memory and attention even after four weeks of abstinence, confirming previous studies that had disclosed such cognitive impairments.

Differences in biomarkers of crack-cocaine adolescent users before/after abstinence

AimsTo measure the variation in Brain-Derived Neurotrophic Factor (BDNF), Thiobarbituric Acid Reactive Substances (TBARS) and interleukin (IL) levels in crack-cocaine dependent adolescents after 21days of abstinence, comparing to levels found in a group of healthy controls. DesignCross-sectional nested on a short follow-up study. SettingTwo inpatient treatment units for adolescents, and a low-income neighborhood. Participants90 adolescents, of both genders, with diagnosis of crack cocaine dependence, and 81 healthy adolescents. MeasurementsSerum levels of IL-6, IL-10, TBARS and BDNF were assessed on admission and discharge. Drug addiction severity was assessed by the Addiction Severity Index − Teen Version (T-ASI) and Cocaine Craving Questionnaire − Brief version (CCQ-b). Psychiatric comorbidities were assessed by the Schedule for Affective Disorders and Schizophrenia for School-Age Children − Present and Lifetime Version (K-SADS-PL). Generalized Estimating Equations (GEE) were used to estimate the IL-6, IL-10, TBARS and BDNF levels, adjusted for confounders. Hedges' g was used to estimate effect size. FindingsTBARS (p=0.005, d=0.04), IL-6 (p=0.027, d=0.40) and IL-10 (p=0.025, d=0.41) were elevated and BDNF (p<0.001, d=0.62) was reduced (p<0.001), in patients, in comparison to controls, at admission time. Variation in those levels between admission and discharge were not significant. ConclusionsCrack-cocaine use seems to be associated with inflammatory and oxidative imbalances in adolescents.

Accumbens volumes are reduced among crack-cocaine users

The brain reward system is known to be the neuroanatomical basis of addictive behaviors. Systemic, cognitive and functional consequences of crack-cocaine addiction are clinically evident, but the neuroanatomical underpinnigs are not yet well understood. We aim to assess the neuroanatomical differences between crack-cocaine patients and paired healthy controls. Fifteen crack-cocaine patients recently discharged from the Addiction Unit of the Hospital de Clínicas de Porto Alegre and fifteen controls matched for gender, age, education and handedness were scanned using a Philips Achieva 1.5T MRI equipment. All subjects had negative positive tests at admission and patients had at least 15days of detoxification. Active neurologic, inflammatory, cardiovascular or systemic comorbidities were excluded. Subcortical structure volumes were determined using Freesurfer v5.1. Controls had greater volumes in the left accumbens (t=3.604, df=28, p=0.001) compared to patients. Right accumbens volumes were also greater in controls (t=2.098, df=28, p=0.045). Groups did not differ regarding intracranial volumes (p=0.514). This preliminary and innovative data on crack-cocaine dependence suggests that there is a volumetric reduction of the accumbens, a region that has a significant role in motivation, pleasure, reward and reinforcement learning, and it could play a central role in the pathophysiology of this drug addiction. Therefore, these findings may contribute to understand some behavioral and cognitive deficits in this population.

Use of contingency management for crack cocaine dependence in South America: Preliminary results from a randomized clinical trial

Use of contingency management for crack cocaine dependence in South America: Preliminary results from a randomized clinical trial

Crack Cocaine Use in Adolescents: Clinical Characteristics and Predictors of Early Initiation.

To describe the clinical characteristics of adolescents with crack cocaine dependence and possible predictors of transition from drug experimentation to crack cocaine dependence. This cross-sectional study enrolled a consecutive sample of 90 adolescents admitted to a psychiatric inpatient unit in the city of Porto Alegre in southern Brazil for crack cocaine detoxification between May 2011 and November 2012. Comorbid psychological conditions were assessed using the Kiddie-SADS-Present and Lifetime Version, and severity of drug use was assessed using the Teen Addiction Severity Index (T-ASI). Comorbidities were compared with those in a community sample of non-drug using controls (n = 81). Patients' mean age was 15.6 years (85.6% boys, 14.4% girls). Seventy-nine (93.2%) met criteria for cocaine dependence (DSM-IV-TR), while 78 (91.8%) had symptoms consistent with cocaine abuse. All patients had experimented with at least 1 other addictive substance before crack cocaine: 61.4%, tobacco (mean age at first use = 11.61 years); 44.3%, alcohol (age at first use = 12.43 years); and 54.5%, cannabis (age at first use = 12.15 years). Patients had used crack cocaine 23.2 days in the last month, and the mean age at first use of crack cocaine was 13.38 years. The most common psychiatric comorbidity was conduct disorder (81.8%), followed by oppositional defiant disorder (52.3%) and attention-deficit/hyperactivity disorder (44.3%), all of which were more prevalent in the patient population than in controls (P < .001). The T-ASI questionnaire showed severe consequences of drug use in most areas of life assessed. The mean time between onset of drug experimentation and crack cocaine dependence was 2.53 (SD = 1.96) years. When Cox regression models were applied, we found that predictors of earlier progression to using crack cocaine were age at first use of any drug (hazard ratio [HR] = 0.79 [95% CI, 0.71-0.88]; P < .001) and age at admission (HR = 0.7 [95% CI, 0.57-0.87]; P = .001). Patients were found to have a multitude of comorbid conditions, which supports the idea of treatment by a multidisciplinary health care team. For each year of delay in the age at first drug use, the chance of crack cocaine initiation is reduced by 18%. Prevention programs aimed at delaying experimentation with addictive substances, especially "gateway" drugs, could delay the progression to crack cocaine dependence.

Contingency management is effective in promoting abstinence and retention in treatment among crack cocaine users in Brazil: A randomized controlled trial.

Crack cocaine dependence has become a severe public health problem in Brazil, and current psychosocial approaches to this problem have shown little or no effectiveness. Although contingency management is among the most effective behavioral treatments for substance use disorders, it has never been applied in the treatment of crack cocaine-dependent individuals in Brazil. The aim of this study was to evaluate the efficacy of incorporating contingency management into standard outpatient treatment for crack cocaine dependence, as well as the impact that doing so has on treatment attendance, retention in treatment, maintenance of abstinence, and the frequency of substance use. We evaluated 65 treatment-seeking, crack cocaine-dependent individuals, randomized to receive 12 weeks of standard treatment plus contingency management (STCM; n = 33) or 12 weeks of standard treatment alone (STA; n = 32). Those in the STCM group received monetary incentives for being abstinent, earning up to US$235.50 if they remained abstinent throughout the entire treatment period. The STCM group participants attended a mean of 19.5 (SD = 14.9) treatment sessions, compared with 3.7 (SD = 5.9) for the STA group participants (p < .01). Those in the STCM group were 3.8, 4.6, and 68.9 times more likely to be retained in treatment at weeks 4, 8, and 12 than were those in the STA group. The likelihood of detecting 4, 8, and 12 weeks of continuous abstinence was 17.7, 9.9, and 18.6 times higher in the STCM group than in the STA group (p < .05). Compared to the STA group, the STCM group submitted a significantly higher proportion of negative samples for crack cocaine, delta-9-tetrahydrocannabinol, and alcohol (p < .001) when all expected samples were included in the denominator but not when only submitted samples were considered. The average monthly cost/participant for incentives was $29.00. Contingency management showed efficacy in a sample of Brazilian crack cocaine users. The intervention holds promise for broader application in international settings. (PsycINFO Database Record

Ventral medial prefrontal cortex (vmPFC) as a target of the dorsolateral prefrontal modulation by transcranial direct current stimulation (tDCS) in drug addiction.

Here, we report some electrophysiologic and imaging effects of the transcranial direct current stimulation (tDCS) over the dorsolateral prefrontal cortex (dlPFC) in drug addiction, notably in alcohol and crack-cocaine dependence. The low resolution electromagnetic tomography (LORETA) analysis obtained through event-related potentials (ERPs) under drug-related cues, more specifically in its P3 segment (300-500ms) in both, alcoholics and crack-cocaine users, showed that the ventral medial prefrontal cortex (vmPFC) was the brain area with the largest change towards increasing activation under drug-related cues in those subjects that kept abstinence during and after the treatment with bilateral tDCS (2mA, 35cm(2), cathodal left and anodal right) over dlPFC, applied repetitively (five daily sessions). In an additional study in crack-cocaine, which showed craving decreases after repetitive bilateral tDCS, we examined data originating from diffusion tensor imaging (DTI), and we found increased DTI parameters in the left connection between vmPFC and nucleus accumbens (NAcc), such as the number of voxels, fractional anisotropy (FA) and apparent diffusion coefficient (ADC), in tDCS-treated crack-cocaine users when compared to the sham-tDCS group. This increasing of DTI parameters was significantly correlated with craving decreasing after the repetitive tDCS. The vmPFC relates to the control of drug seeking, possibly by extinguishing this behavior. In our studies, the bilateral dlPFC tDCS reduced relapses and craving to the drug use, and increased the vmPFC activation under drug cues, which may be of a great importance in the control of drug use in drug addiction.

Efficacy of topiramate in the treatment of crack cocaine dependence: a double-blind, randomized, placebo-controlled trial.

We performed a double-blind, randomized, placebo-controlled trial to assess the efficacy of topiramate in the treatment of crack cocaine dependence. Sixty men who were dependent on cocaine (DSM-IV) (exclusive use of crack cocaine) were selected. The subjects were randomly assigned to either a topiramate group (subjects received 50-200 mg of topiramate per day for 12 weeks) or a control group (subjects received placebo). The initial daily treatment dose was 50 mg, and this dose was increased weekly at increments of 25 to 50 mg, based on the subject's tolerability, to a maximum of 200 mg. All of the subjects also participated in motivational interviews and group therapy. The primary outcome measures were detection of benzoylecgonine in the urine, study retention, frequency of cocaine smoking, amount of cocaine use, and mean amount of money spent on cocaine per week. The study was conducted from February 2013 to February 2014. Twenty-nine subjects in the topiramate group and 29 subjects in the control group completed the study. Longitudinal assessment revealed that retention was not significant (odds ratio [OR] = 1.072, P = .908) between the 2 groups. Negative results from a urine test for benzoylecgonine (a cocaine metabolite), which is a measure of cocaine abstinence, were more frequently obtained from the topiramate group (OR = 8.687, P < .001). Topiramate reduced the quantity of cocaine used (mean reduction = -3.108 g, P < .001), the frequency of cocaine use (mean = -0.784 times per week, P = .005), and the amount of money spent on cocaine (mean [US dollars] = -$25.38, P = .015; this variable did not achieve statistical significance after Bonferroni correction) compared with the placebo during the 12 weeks (or 84 days) of the assessment. However, the differences in reductions between the 2 groups in the quantity of cocaine used, the frequency of cocaine use, and money spent on cocaine over time (time × group interaction) were present only during the first 4 weeks, and none of these variables by 12 weeks. The studied groups did not differ with regard to secondary end points, such as study dropout and the number of subjects who reported side effects. The present findings indicate that topiramate is effective and safe and thus reinforce previous data suggesting that topiramate is a potentially useful treatment for crack cocaine dependence. However, we found that topiramate is only useful as an adjunctive treatment during the first 4 weeks of the treatment. Future studies with larger samples are needed to confirm these results. Registro Brasileiro de Ensaios Clínicos (ReBEC) RBR-3vwfjs and UTN: U1111-1131-4443.

Crack-cocaine dependence and aging: effects on working memory.

Objective:To compare the working memory (WM) performance of young adult crack-cocaine dependent users, healthy older adults, and a control group of healthy young adults.Methods:A total of 77 female participants took part in this study: 26 young adult crack-cocaine dependent users (CRK), 19 healthy older adults (HO), and 32 healthy younger adults (HC). All participants completed the N-back verbal task.Results:A multivariate analysis of covariance was performed. The model included education, income, and medication use as covariates. A group effect (F6,140 = 7.192, p < 0.001) was found. Post-hoc analyses showed that the performance of the CRK and HO groups was reduced compared to the HC group in two N-back conditions. No differences between the HO and CRK groups on WM performance were found.Conclusions:CRK participants perform similar to HO participants on a WM task, despite the well-known effects of age on WM and the young age of CRK. These data point to a possible parallel between cognitive declines associated with crack use and developmental aging.

A Randomized Placebo-Controlled Trial of Targeted Prefrontal Cortex Modulation with Bilateral tDCS in Patients with Crack-Cocaine Dependence.

Background:Transcranial direct current stimulation over the dorsolateral prefrontal cortex has been shown to be clinically useful in the treatment of drug addiction.Methods:We conducted a double-blind randomized clinical trial aiming to assess the effects of bilateral dorsolateral prefrontal cortex transcranial direct current stimulation (left cathodal/right anodal) on crack-cocaine addiction. We defined craving as the primary outcome, and other clinical measurements, including depressive and anxiety symtoms, and quality of life, as secondary outcomes. Seventeen male crack-cocaine users (mean age 30.4±9.8 SD) were randomized to receive 5 sessions of active transcranial direct current stimulation (2 mA, 35cm2, for 20 minutes), every other day, and 19 males (mean age 30.3±8.4 SD) to receive sham-transcranial direct current stimulation (placebo) as control group.Results:Craving scores were significantly reduced in the transcranial direct current stimulation group after treatment when compared with sham-transcranial direct current stimulation (P=.028) and baseline values (P=.003), and decreased linearly over 4 weeks (before, during, and after treatment) in the transcranial direct current stimulation group only (P=.047). Changes of anxiety scores towards increase in the sham-transcranial direct current stimulation and decrease in the transcranial direct current stimulation group (P=.03), and of the overall perception of quality of life (P=.031) and of health (P=.048) towards decrease in the sham-transcranial direct current stimulation group and increase in the transcranial direct current stimulation group differed significantly between groups.Conclusions:Repetitive bilateral transcranial direct current stimulation over the dorsolateral prefrontal cortex reduced craving for crack-cocaine use, decreased anxiety, and improved quality of life. We hypothesize that transcranial direct current stimulation effects may be associated with increased prefrontal processing and regulation of craving behavior.

Modafinil in the treatment of crack-cocaine dependence in the Netherlands: Results of an open-label randomised controlled feasibility trial

Crack-cocaine dependence is a serious disorder with no approved pharmacological treatment. Modafinil is a promising medication with increased cocaine abstinence and reduced craving in some previous studies. In the present study, we examined the acceptance, safety and potential benefits of modafinil as an add-on treatment to cognitive behavioural therapy (CBT) in crack-cocaine dependent patients. Sixty-five crack-cocaine dependent outpatients participated in an open-label, randomised feasibility trial. Patients were randomised to receive either 12-week individual CBT plus 400 mg/day modafinil or 12-week individual CBT only. The primary outcome measure was CBT treatment retention. Secondary outcomes included modafinil adherence, tolerability and safety, use of cocaine and other substances, cocaine craving, health, social functioning and patient satisfaction. Modafinil adherence was low, with only 10% treatment completers. Intent-to-treat analyses showed that modafinil did not improve CBT treatment retention or any of the secondary cocaine-related outcomes. Both groups showed similar, large reductions in cocaine use during the study treatment. Post hoc exploratory analyses within the CBT plus modafinil group showed significantly larger baseline to week 12 reductions in cocaine use days in high (⩾ 8 weeks) modafinil adherent patients. Acceptance and benefits of modafinil were not demonstrated in the present study. Since reduction in cocaine use was observed in high modafinil adherent patients, further research in the treatment of cocaine dependence, in which modafinil adherence is optimised, is warranted.