Cocaïne et alcool : des liaisons dangereuses

[Drug use and treatment misuse: Key points on polydrug use]

Problematic use of psychoactive drugs, be it legal, on prescription, or not, remains a broad phenomenon when taken as a whole, with an increasingly large spectrum of used products. The polysubstance drug use is an expanding new trend. Although its epidemiological analysis is complex, needing further research, certain patterns of drug combinations can be found, allowing to identify clusters of users associated to more specific medical and social risks. Managing polysubstance users involves assessing each drug use, but also the connections between drugs and the patient's expectations for each of them. Complications, as well as psychiatric and somatic comorbidities are to be taken into account. The therapeutic tools for polysubstance drug use, mainly pharmacological, are still often limited to the sum of specific tools for each product. Prevention is crucial but has to adapt to the identified use clusters, and the gender. Notably, a good knowledge of chronic pain management and prescribed drug dependency risks is required to prevent polysubstance drug use involving opioids.

Nalmefene is effective at reducing alcohol seeking, treating alcohol-cocaine interactions and reducing alcohol-induced histone deacetylases gene expression in blood

BACKGROUND AND PURPOSE

The opioid antagonist nalmefene (selincro®) was approved for alcohol-related disorders by the European Medicines Agency in 2013. However, there have been no studies regarding the effectiveness of nalmefene when alcohol is used in combination with cocaine.

EXPERIMENTAL APPROACH

Using operant alcohol self-administration in Wistar rats and qRT-PCR, we evaluated (i) the dose-response curve for s.c. and p.o. nalmefene; (ii) the effects of nalmefene with increasing concentrations of alcohol; (iii) the efficacy of nalmefene on cocaine-potentiated alcohol responding; and (iv) the gene expression profiles of histone deacetylases (Hdac1-11) in peripheral blood in vivo and in the prefrontal cortex, heart, liver and kidney post mortem.

KEY RESULTS

S.c. (0.01, 0.05, 0.1 mg·kg(-1) ) and p.o. (10, 20, 40 mg·kg(-1) ) nalmefene dose-dependently reduced alcohol-reinforced responding by up to 50.3%. This effect of nalmefene was not dependent on alcohol concentration (10, 15, 20%). Cocaine potentiated alcohol responding by approximately 40% and nalmefene (0.05 mg·kg(-1) ) reversed this effect of cocaine. Alcohol increased Hdac gene expression in blood and nalmefene prevented the increases in Hdacs 3, 8, 5, 7, 9, 6 and 10. In the other tissues, alcohol and nalmefene either did not alter the gene expression of Hdacs, as in the prefrontal cortex, or a tissue-Hdac-specific effect was observed.

CONCLUSIONS AND IMPLICATIONS

Nalmefene might be effective as a treatment for alcohol-dependent patients who also use cocaine. Also, the expression of Hdacs in peripheral blood might be useful as a biomarker of alcohol use and drug response.

Ethanol and cocaine: environmental place conditioning, stereotypy, and synergism in planarians

More than 90% of individuals who use cocaine also report concurrent ethanol use, but only a few studies, all conducted with vertebrates, have investigated pharmacodynamic interactions between ethanol and cocaine. Planaria, a type of flatworm often considered to have the simplest 'brain,' is an invertebrate species especially amenable to the quantification of drug-induced behavioral responses and identification of conserved responses. Here, we investigated stereotypical and environmental place conditioning (EPC) effects of ethanol administered alone and in combination with cocaine. Planarians displayed concentration-related increases in C-shaped movements following exposure to ethanol (0.01-1%) (maximal effect: 9.9±1.1 C-shapes/5 min at 0.5%) or cocaine (0.1-5 mM) (maximal effect: 42.8±4.1 C-shapes/5 min at 5 mM). For combined administration, cocaine (0.1-5 mM) was tested with submaximal ethanol concentrations (0.01, 0.1%); the observed effect for the combination was enhanced compared to its predicted effect, indicating synergism for the interaction. The synergy with ethanol was specific for cocaine, as related experiments revealed that combinations of ethanol and nicotine did not result in synergy. For EPC experiments, ethanol (0.0001-1%) concentration-dependently increased EPC, with significant environmental shifts detected at 0.01 and 1%. Cocaine (0.001-1 μM) produced an inverted U-shaped concentration-effect curve, with a significant environmental shift observed at 0.01 μM. For combined exposure, variable cocaine concentrations (0.001-1 μM) were administered with a statistically ineffective concentration of ethanol (0.0001%). For each concentration of cocaine, the environmental shift was enhanced by ethanol, with significance detected at 1 μM. Cocaethylene, a metabolite of cocaine and ethanol, also produced C-shapes and EPC. Lidocaine (0.001-10 μM), an anesthetic and analog of cocaine, did not produce EPC or C-shaped movements. Evidence from planarians that ethanol produces place-conditioning effects and motor dysfunction, and interacts synergistically with cocaine, suggests that aspects of ethanol neuropharmacology are conserved across species.

Static posturography in addicted to illicit drugs and alcohol

The use of illicit drugs and alcohol can affect body balance.

AIM

To evaluate balance control with static posturography in individuals addicted to illicit drugs, with or without alcohol abuse.

STUDY DESIGN

Case-control, prospective.

METHODS

47 users of illicit drugs, with or without alcohol abuse, and a homogeneous control group consisting of 47 healthy individuals were submitted to a neurotological evaluation including Balance Rehabilitation Unit posturography.

RESULTS

The stability threshold mean values were significantly lower (p < 0.0001) in users of illicit drugs, with or without alcohol abuse when compared to the control group; the mean values for sway velocity and ellipse area in all evaluated conditions were significantly higher (p <0.05) in the experimental group when compared to the control group, except for the ellipse area in static force surface and opened eyes (p = 0.168).

CONCLUSION

The balance control of individuals addicted to illicit drugs with or without alcohol abuse could present stability threshold, sway velocity and ellipse area abnormalities in static posturography.

[Addiction to cocaine and other stimulants]

Due to many available forms (powder, pasta base, freebase and crack…) and because of multiple routes of administration (intranasal, intravenous, or smoked), cocaine has become in 30 years one of the most consumed illegal drugs worldwide, after cannabis. While the frequency of consumption decreases in North America, it continues to rise in Europe, and in some countries in South America, including Brazil, despite a growing knowledge of its specific effects, physical complications and psychiatric consequences. Elsewhere (notably in Asia and Indian Ocean), amphetamine and other stimulants (including methamphetamine), whose properties and patterns of use are very similar to those of cocaine, tend to replace it. Another amphetamine derivative, MDMA or ecstasy, is also consumed by many young people of less than 25 years, in Europe and North America, in a festive setting, with specific consequences and special procedures of care. Although there is currently no consensus for a specific medication, the most appropriate therapeutic approach seems to involve a psychosocial treatment associated with an anticraving medication, which will reduce compulsive desire to consume, in order to facilitate the psychotherapeutic and social care. However, pharmacological research remains very active, and many options are explored (GABAergic or dopaminergic agonists, amphetamine derivatives with long half-life, vaccine…), whether to treat addiction to cocaine or to methamphetamine.

Alcohol-related brief intervention in patients treated for opiate or cocaine dependence: a randomized controlled study

BACKGROUND

Despite the importance of heavy drinking and alcohol dependence among patients with opiate and cocaine dependence, few studies have evaluated specific interventions within this group. The aim of the present study was to evaluate the impact of screening with the Alcohol Use Disorders Identification Test (AUDIT) and of brief intervention (BI) on alcohol use in a sample of patients treated for opioid or cocaine dependence in a specialized outpatient clinic.

METHODS

Adult outpatients treated for opioid or cocaine dependence in Switzerland were screened for excessive alcohol drinking and dependence with the AUDIT. Patients with AUDIT scores that indicated excessive drinking or dependence were randomized into two groups--treatment as usual or treatment as usual together with BI--and assessed at 3 months and 9 months.

RESULTS

Findings revealed a high rate (44%) of problematic alcohol use (excessive drinking and dependence) among patients with opiate and cocaine dependence. The number of drinks per week decreased significantly between T0 (inclusion) and T3 (month 3). A decrease in average AUDIT scores was observed between T0 and T3 and between T0 and T9 (month 9). No statistically significant difference between treatment groups was observed.

CONCLUSIONS

In a substance abuse specialized setting, screening for alcohol use with the AUDIT, followed by feedback on the score, and use of alcohol BI are both possibly useful strategies to induce changes in problematic alcohol use. Definitive conclusions cannot, however, be drawn from the study because of limitations such as lack of a naturalistic group. An important result of the study is the excellent internal consistency of AUDIT in a population treated for opiate or cocaine dependence.