Acute and non-acute effects of cannabis in adolescents and adults

Preclinical research demonstrates that cannabinoids have differing effects in adolescent and adult animals, and human epidemiological research suggests that adolescent cannabis use has greater potential for harm than adult use. In chapters 1 and 2, I review this literature, describing the acute and non-acute effects of cannabis on memory, response inhibition and psychotic-like symptoms, with a focus on findings relating to adolescent populations and age of cannabis use onset. In chapter 3, I describe associations between adolescent cannabis use, IQ and educational performance, demonstrating that adjustment for potential confounders – most notably cigarette use – leaves cannabis use not associated with lower performance. In chapter 4, I describe the first study to compare the acute effects of cannabis in human adolescent (n=20; 16-17 years old) and adult (n=20; 24-28 years old) male cannabis users, in a placebo-controlled, double-blind cross-over design. After inhaling vaporised active or placebo cannabis, participants completed tasks assessing memory, inhibition, alongside physiological measures and subjective drug effects (e.g. “stoned”). Results showed contrasting profiles of adolescent resilience (blunted subjective, physiological and memory effects) and vulnerability (lack of satiety, impaired inhibitory processes). In chapter 5, in the same sample, I describe the acute psychotic-like effects of cannabis. Cannabis increased psychotic-like symptoms and the incidence of speech illusions in both adolescents and adults, though some self-rated effects were heightened in adults. In chapter 6, in a reduced sample, I describe the acute effects of cannabis on anhedonia (as indexed by reward responsivity, hedonic capacity and self-rated anhedonia) in adolescents (n=13) and adults (n=13). Cannabis did not affect reward responsivity or hedonic capacity in either group, though adults but not adolescents reported self-rated increases in anhedonia. In chapter 7, I integrate my findings, discuss their implications, consider limitations and suggest directions for future research into the effects of cannabis use in adolescence

Dyrektywa 2011/83/UE z dnia 25 października 2011 r. w sprawie praw konsumentów jako kolejny etap na drodze tworzenia jednolitych reguł konkurencji na unijnym rynku

W dniu 25 października 2011 r. przyjęta została dyrektywa w sprawie praw konsumentów uchylająca dyrektywę 85/577/EWG w sprawie umów zawartych poza lokalem przedsiębiorstwa i dyrektywę 97/7/WE w sprawie umów zawieranych na odległość i zmieniająca dyrektywę 93/13/EWG w sprawie nieuczciwych warunków w umowach konsumenckich i dyrektywę 1999/44/WE w sprawie sprzedaży konsumenckiej i gwarancji. Stanowi ona kolejny krok na drodze doprecyzowania i dostosowania tradycyjnych zasad świętości i wolności umów do współczesnych warunków rynkowych. Jednocześnie jest wynikiem kompromisu wieńczącego kilkuletnią dyskusję na temat zastąpienia w regulowanym obszarze harmonizacji minimalnej harmonizacją zupełną. Wprowadzając harmonizację zupełną w zakresie objętym uchylonymi dyrektywami, stanowi przełom w dotychczas stosowanej w tworzeniu unijnego prawa konsumenckiego metodzie ustalania standardów minimalnej ochrony konsumenta. Wytycza ona nowy kierunek rozwoju unijnego prawa konsumenckiego: należy oczekiwać, że, podobnie jak to nastąpiło w odniesieniu do umów nietypowych (zawieranych poza lokalem przedsiębiorstwa oraz umów na odległość – w tym w handlu elektronicznym), także w obszarze tradycyjnych umów, z historycznie ukształtowanymi różnicami w regulacjach krajowych, stopniowo ujednolicone zostaną reguły gry na rynku wewnętrznym UE. Artykuł zawiera przede wszystkim ocenę dyrektywy w sprawie praw konsumentów z punktu widzenia jej skutków dla przedsiębiorstw i konsumentów oraz zadań ustawodawcy krajowego

Are IQ and educational outcomes in teenagers related to their cannabis use? A prospective cohort study

The UK Medical Research Council (MRC), Wellcome Trust and University of Bristol provide core support for ALSPAC. This research was specifically funded by an MRC Studentship awarded to the first autho

UNFAIRNESS DOCTRINE I PODEJŚCIE EKONOMICZNE DO OCHRONY KONSUMENTÓW W PRAKTYCE FEDERALNEJ KOMISJI HANDLU W USA

Starting from the concept of treating the protection of consumers’ interests as a necessary element of market order, the U.S. federal law has created a pattern of protection against unfair or misleading acts or market practices, perceived from the perspective of their effects on consumers, competitive relationships, and the functioning of the market mechanism. Such  a  comprehensive  perspective  justifies  the  economic  approach  to  the  regulation of unfair market practices. At the same time, it is intriguing to search for answers to the question of the possibility and desirability of applying elements of economic analysis of law with respect to the interpretation of unfairness to the consumer (unfairness doctrine).Wychodząc z koncepcji potraktowania ochrony interesów konsumentów jako koniecznego elementu ochrony ładu rynkowego, federalne prawo USA stworzyło wzorzec ochrony przed nieuczciwymi lub wprowadzającymi w błąd działaniami lub praktykami rynkowymi, postrzeganymi z perpektywy ich skutków zarówno dla konsumentów jak i dla relacji konkurencyjnych i funkcjonowania mechanizmu rynkowego. Taka kompleksowa perspektywa uzasadnia podejście ekonomiczne do regulowania nieuczciwych praktyk rynkowych. Jednocześnie frapujące jest poszukiwanie odpowiedzi na pytanie o możliwość i celowość stosowania elementów ekonomicznej analizy prawa w odniesieniu do interpretowania nieuczciwości wobec konsumenta (unfairness doctrine)

Are adolescents more vulnerable to the harmful effects of cannabis than adults? A placebo-controlled study in human males

Preclinical research demonstrates that cannabinoids have differing effects in adolescent and adult animals. Whether these findings translate to humans has not yet been investigated. Here we believe we conducted the first study to compare the acute effects of cannabis in human adolescent (n=20; 16-17 years old) and adult (n=20; 24-28 years old) male cannabis users, in a placebo-controlled, double-blind cross-over design. After inhaling vaporized active or placebo cannabis, participants completed tasks assessing spatial working memory, episodic memory and response inhibition, alongside measures of blood pressure and heart rate, psychotomimetic symptoms and subjective drug effects (for example, 'stoned', 'want to have cannabis'). Results showed that on active cannabis, adolescents felt less stoned and reported fewer psychotomimetic symptoms than adults. Further, adults but not adolescents were more anxious and less alert during the active cannabis session (both pre- and post-drug administration). Following cannabis, cognitive impairment (reaction time on spatial working memory and prose recall following a delay) was greater in adults than adolescents. By contrast, cannabis impaired response inhibition accuracy in adolescents but not in adults. Moreover, following drug administration, the adolescents did not show satiety; instead they wanted more cannabis regardless of whether they had taken active or placebo cannabis, while the opposite was seen for adults. These contrasting profiles of adolescent resilience (blunted subjective, memory, physiological and psychotomimetic effects) and vulnerability (lack of satiety, impaired inhibitory processes) show some degree of translation from preclinical findings, and may contribute to escalated cannabis use by human adolescents

What are the psychological effects of using synthetic cannabinoids? A systematic review

Background: Synthetic cannabinoids are, typically, full agonists at the cannabinoid CB1 receptor, and therefore considerably more potent than natural cannabis and may have correspondingly more serious psychological effects. Despite government sanctions against their production they continue to be available in ever-increasing varieties over the Internet. The psychological consequences of synthetic cannabinoid use are relatively unknown. Aim: The purpose of this study was to synthesise the available research on the psychological consequences of synthetic cannabinoid use. Method: A literature search of three databases was conducted in February 2018, including the following keywords: Spice, synthetic cannabis, cognition, affect, behaviour, psychosis, depression and anxiety. Results: Seventeen studies involving a variety of participants were eligible for inclusion: one controlled administration study, seven cross-sectional studies, five Internet surveys and four qualitative studies. The controlled administration study showed that, compared to placebo, synthetic cannabinoids acutely affected some aspects of cognitive functioning and subjective psychological ratings. Non-controlled, cross-sectional studies generally showed that synthetic cannabinoid users had lower performance on cognitive tasks and showed elevated symptomatology (e.g. paranoia) compared to both natural cannabis and non-cannabis users. Methodological limitations were noted across different study designs. There is limited research on how doses, frequency or type of synthetic cannabinoid influence outcomes. Conclusions: Acute synthetic cannabinoid use can result in a range of psychological outcomes and, when non-intoxicated, synthetic cannabinoid users appear to differ from natural cannabis and non-users on various affective and cognitive domains. As synthetic cannabinoid use is increasing in at-risk populations there is an urgent need for more and better research to inform users, professionals and policymakers

How does cannabidiol (CBD) influence the acute effects of delta-9-tetrahydrocannabinol (THC) in humans? A systematic review

The recent liberalisation of cannabis regulation has increased public and scientific debate about its potential benefits and risks. A key focus has been the extent to which cannabidiol (CBD) might influence the acute effects of delta-9-tetrahydrocannabinol (THC), but this has never been reviewed systematically. In this systematic review of how CBD influences the acute effects of THC we identified 16 studies involving 466 participants. Ten studies were judged at low risk of bias. The findings were mixed, although CBD was found to reduce the effects of THC in several studies. Some studies found that CBD reduced intense experiences of anxiety or psychosis-like effects of THC and blunted some of the impairments on emotion and reward processing. However, CBD did not consistently influence the effects of THC across all studies and outcomes. There was considerable heterogeneity in dose, route of administration and THC:CBD ratio across studies and no clear dose-response profile emerged. Although findings were mixed, this review suggests that CBD may interact with some acute effects of THC.</p

Does variation in trait schizotypy and frequency of cannabis use influence the acute subjective, cognitive and psychotomimetic effects of delta-9-tetrahydrocannabinol?:A mega-analysis

BACKGROUND: While the acute effects of cannabis are relatively benign for most users, some individuals experience significant adverse effects. This study aimed to identify whether variation in schizotypal personality traits and frequency of cannabis use influence the acute effects of delta-9-tetrahydrocannabinol (THC).METHODS: Individual participant data from four double-blind, randomised, placebo-controlled, acute crossover studies involving 128 cannabis users were combined for a mega-analysis. Using multilevel linear models and moderation analyses, frequency of cannabis use and schizotypal personality traits were investigated as potential moderators of the subjective, cognitive and psychotomimetic effects of acute THC.RESULTS: There was evidence of a moderating effect where increased frequency of cannabis use was associated with reduced intensity of subjective (changes in alertness and feeling stoned) and psychosis-like effects following THC when compared with placebo. Moderating effects of cannabis use frequency on acute memory impairment were weak. Trait schizotypy did not moderate the acute psychosis-like effects of THC compared with placebo.CONCLUSIONS: Our results suggest that a pattern of domain-specific tolerance develops to the acute effects of THC. Tolerance to the alertness-reducing effects occurred more readily than tolerance to psychotomimetic effects. Only partial tolerance to feeling stoned was found, and there was weak evidence for tolerance to memory impairment. Trait schizotypy did not moderate THC's effects on psychotomimetic symptoms.</p