Current Drug Abuse Reviews - Volume 4, Issue 2, 2011

The desire to feel good expresses itself in pleasure seeking behavior. One way this can be achieved is via mood alteration caused by alcohol, nicotine and drugs. The fundamental question how the pursuit for pleasure can result in loss of control, dependence or addiction may be elucidated by looking at differences between hawk-type and dove-type personalities. Maynard Smith and Price [1, 2] proposed the Hawk-Dove model to explain the success of an individual's behavior in a population. The ‘ hawk’ initiates impulsive and aggressive behavior (not stopping until injured or until the opponent backs down). Hawk-types are characterized by high levels of risk-taking behavior and hostility (first do, than think). In contrast, dovetypes retreat immediately if the opponent initiates aggressive behavior and will not fight under any circumstances, i.e. behavior that is characterized by low levels of risk-taking behavior and hostility (first think, then do). Research suggests that high levels of aggression and risk taking behavior are associated with alcohol and drug abuse [3, 4]. Therefore, it can be hypothesized that hawk-types are more likely to develop alcohol and drug dependence than dove-types. Whereas dove-types are capable of adapting lifestyle to circumstances and environmental changes, hawk-types are much more likely to persist in stereotype behavior [5]. Given this difference, it might be further postulated that hawk-types are less likely to be successful in quitting or reducing alcohol and drug use. Research indeed showed that high risk takers are less likely to alter smoking behavior [6]. Prenatal testosterone is important in the development of masculine characteristics such as aggression and strength. Amnionic fluid sample analysis revealed a significant relationship between prenatal testosterone - produced by the fetus - and social behavior in young children [7], adult aggression and risk taking [8, 9]. Prenatal testosterone therefore seems an important factor in determining whether the individual becomes a hawk- or dove-type. If the hawk-dove type model is useful to distinguish between people who are at risk for alcohol and drug abuse, it is important to have an objective biomarker or other correlate of prenatal testosterone that can be measured after birth. One of these correlates can be the 2D:4D digit ratio, since it is thought that prenatal testosterone affects digit length during development in the womb (Manning 2002). Digit growth is controlled by Hox genes [10], which is influenced by testosterone levels. High levels of testosterone increase the length of the fourth digit (ring finger) to a greater extent than the second digit (index finger). Hence, the 2D:4D digit ratio was suggested as biological correlate for prenatal testosterone exposure [11]. Importantly, the 2D:4D digit ratio does not change after the age of 2 [12, 13]. Hence, when measured in adults it provides valuable information about prenatal exposure to testosterone. After measuring finger length (see Fig. 1), the 2D:4D digit ratio can be easily calculated. If the ratio is less than 1, its more likely to be a hawk-type, if the ratio is greater than 1 it is more likely to be a dovetype....

This review presents the theoretical model, evidence base, and theoretical and methodological issues for seven treatment approaches to gambling disorders: 1) psychoanalytic and psychodynamic treatments; 2) Gamblers Anonymous; 3) behavioural treatments; 4) cognitive and cognitive-behavioural therapies; 5) brief, motivational, and self-directed interventions; 6) pharmacotherapies, and 7) family therapy approaches. Throughout the review, broader clinical and research issues are also discussed, including barriers to treatment-seeking, controlled gambling versus abstinence as a treatment goal, comorbidity, and the evaluation of treatment efficacy and effectiveness.

Although the prevalence of co-use of cannabis and 3,4-methylenedioxymethamphetamine (MDMA) is very common among polydrug users in western societies, few studies have tested the consequences on behavior, cognition or neurobiology. This review examines 23 articles published between 2002 and 2010 with an explicit focus on the combination, or administration, of MDMA and cannabis or cannabinoid agents. The aim was to provide a short overview on the latest human research concerning cognitive effects of co-consumption of MDMA and cannabis, and a more elaborate picture of the state of knowledge about the interaction of cannabinoid agents and MDMA from animal studies. It was found that recent retrospective studies on cognitive functions in long-term drug abusers point to an additive negative effect on different types of memory, as well as a cannabis-independent decrease in learning and decision-making in MDMA users. Behavioral experiments in rodents and in vitro studies investigating the combined effect of MDMA and cannabinoid agents demonstrate modulator effects of acute co-administration on measures like body temperature, conditioned reinforcement, and presumed neurotoxicity. As neural mechanism underlying these changes, an interaction between the cannabinoid system, especially cannabinoid receptor 1, and the serotonergic and dopaminergic system in the prefrontal cortex, nucleus accumbens, and hippocampus is suggested. In conclusion, there are few and somewhat contradictory studies examining the effects of co-use of these drugs on cognitive measures like impulsivity, memory and executive functions or underlying neurobiological alterations, and a shortage of animal studies examining long-term effects of chronic co-administration.

Abuse of sildenafil has been reported since its introduction in 1999 and commonly documented in combination with illicit drugs among men and women of all ages. Increased risks of sexually transmissible diseases including HIV have been associated with sildenafil use in men who have sex with men. Recognizing the abuse potential of phosphodiesterase type 5 inhibitors (PDE5), we aim to summarize the current knowledge of this abuse. An investigation of EMBASE, PubMed, the Food and Drug Administration (FDA) website, MedWatch, and search engines was performed to evaluate information regarding sildenafil, tadalafil, and vardenafil abuse. The EMBASE search provided 46 articles fitting the search criteria and evaluation led to 21 separate publications with specific information regarding PDE5 abuse. A PubMed search found 10 additional publications. MedWatch reported 44 separate warnings since 2000, most of which reported contamination of herbal products with active drug components. Few reports of abuse were among the 14,818 reports in the FDA AERS for sildenafil. A search for “internet drug store” revealed 6.4 million hits and of 7000 internet pharmacies identified by the Verified Internet Pharmacy Practice Sites Program (VIPPS) only 4% were in proper compliance. The role internet pharmacies play in counterfeit PDE5 or abuse is not well documented; however based on easy access, direct patient marketing, and low advertised cost it is likely this role is underreported. Currently the best recommendation for providers is to recognize the possibility of abuse and to educate patients on risks of this behavior.

The toxicity of cocaine and crack was studied on the protozoan Tetrahymena pyriformis, using several endpoints, such as the DNA content of the macronuclei and the phagocytic ability. Both forms induced an increase in the DNA content of the protozoan, which indicates the stimulation of the mitotic process. In contrast, the phagocytic activity of the protozoan was decreased after the administration of cocaine, an effect that was more extensive after the administration of crack. These results, derived from previous experiments, suggest a possible relationship between the observed immunosuppression in cocaine abusers and the immunosuppression found in the protozoan. This suppression subsequently may play a role in the development of other opportunistic infections in drug abusers. This paper, based on in vivo experiments with the protozoan Tetrahymena, suggests the compromised immune response in cocaine addicts and assures the reported effects of cocaine on immune cell function.

Introduction: Sports participation, while offering numerous developmental benefits for adolescents, has been associated with alcohol use in prior research. However, the relationship between sports participation and alcohol use among adolescents remains unclear, particularly how research design elements impact evidence of this relationship. We reviewed the evidence regarding sports participation and alcohol use among adolescents, with a focus on examining the potential impact of research design elements on this evidence. Methods: Studies were assessed for eligibility and coded based on research design elements including: study design, sampling method, sample size, and measures of sports participation and alcohol use. Results: Fifty-four studies were assessed for eligibility, 29 of which were included in the review. Nearly two-thirds used a cross-sectional design and a random sampling method, with sample sizes ranging from 178 to 50,168 adolescents (Median = 1,769). Sixteen studies used a categorical measure of sports participation, while 7 applied an index-type measure and 6 employed some other measure of sports participation. Most studies assessed alcohol-related behaviors (n = 18) through categorical measures, while only 6 applied frequency only measures of alcohol use, 1 study applied quantity only measures, and 3 studies used quantity and frequency measures. Conclusions: Sports participation has been defined and measured in various ways, most of which do not differentiate between interscholastic and community-based contexts, confounding this relationship. Stronger measures of both sports participation and alcohol use need to be applied in future studies to advance our understanding of this relationship among youths.

Nicotine, the primary psychoactive compound in tobacco, is responsible for the addictive effects of smoking; however, there is a paucity of information indicating whether the presence of other biological chemicals in tobacco alters nicotine's rewarding effects. It has been suggested that the addictive effects of smoking may be due, in part, to the inhibition of the pair of monoamine oxidase enzymes responsible for a significant fraction of monoamine metabolism, Monoamine Oxidase A and B (MAO-A and MAO-B). This paper reviews the current, limited literature examining the role of MAO inhibition on the rewarding effects of nicotine (e.g., self-administration) in rodents. Overall, studies with rats and mice do suggest that MAO plays a role in nicotine reward. However, results are mixed regarding the MAO subtype responsible for the rewarding effects of nicotine, most likely due to methodological variation across the limited number of studies. Important individual difference factors such as age, sex and genetics are discussed, along with relevant brain and neurotransmitter systems. Future research is needed that builds on the available literature to map out the relationship between MAO inhibition and nicotine reward. These data will enhance our understanding of the neuropharmacological effects of smoking and the value of implementing MAO inhibitors as pharmacotherapies for smoking cessation.

Recently, a new class of “designer drugs” has emerged on the drug use market, known as “legal highs” or “herbal highs”. They include a wide range of products, from natural plant-originated substances to synthetic compounds, that can be purchased both online and from high street retailers. “Legal highs” mimic psychoactive effects of illicit drugs of abuse. However, they are claimed to consist of compounds that are legal to sell, possess and use. Based on the spectrum of their actions on the cognitive processes, mood, and behavior “legal highs” can be classified into three basic categories: amphetamine- and ecstasy-like psychostimulants, hallucinogens, and synthetic cannabinoids (“spice”). This review surveys the current state of knowledge regarding the pharmacological properties of “legal highs”. It also addresses the negative consequences of using these products.