Previous studies have suggested that marijuana (cannabis sativa) and delta-9-tetrahydrocannabinol (D9-THC), the major psychoactive ingredient of marijuana, are effective in the therapy of tics and associated behavioral disorders in Tourette Syndrome (TS). Because there is also evidence that cannabis sativa may cause cognitive impairment in healthy users, we performed a randomized double-blind placebocontrolled crossover trial for D9-THC in 12 adult TS patients to investigate whether treatment of TS with a single dose of D9-THC at 5.0 to 10.0 mg causes significant side effects on neuropsychological performance. Using a variety of neuropsychological tests, we found no significant differences after treatment with D9-THC compared to placebo...

Abstract Purpose: Colon cancer is a major public health problem. Cannabis-based medicines are useful adjunctive treatments in cancer patients. Here, we have investigated the effect of a standardized Cannabis sativa extract with high content of cannabidiol (CBD), here named CBD BDS, i.e. CBD botanical drug substance, on colorectal cancer cell proliferation and in experimental models of colon cancer in vivo. Methods: Proliferation was evaluated in colorectal carcinoma (DLD-1 and HCT116) as well as in healthy colonic cells using the MTT assay. CBD BDS binding was evaluated by its ability to displace [(3)H]CP55940 from human cannabinoid CB1 and CB2 receptors. In vivo, the effect of CBD BDS...

The cannabinoid receptor agonist delta9 -tetrahydrocannabinol (THC) enhances the antinociceptive effects of mu opioid receptor agonists, raising the possibility of using a combination of THC and opioids for treating pain. This study examined the effects of noncontingent and contingent administration of THC on i.v. heroin self-administration in rhesus monkeys. Self-administration of different unit doses of heroin (0.0001–0.1 mg/kg/infusion) generated a typical inverted U-shaped dose-response curve. In one experiment (n=4), noncontingent THC (0.1–1.0 mg/kg) dosedependently shifted the heroin dose-response curve downward in three monkeys and slightly leftward in one monkey. In a second experiment (n=4), monkeys could self-administer THC alone (0.0032–0.032 mg/kg/infusion), heroin alone, or...

Cannabinoids exert antiproliferative effects in a wide range of tumoral cells, including hepatocellular carcinoma (HCC) cells. In this study, we examined whether the PPARc-activated pathway contributed to the antitumor effect of two cannabinoids, D9-tetrahydrocannabinol (THC) and JWH-015, against HepG2 and HUH-7 HCC cells. Both cannabinoids increased the activity and intracellular level of PPARc mRNA and protein, which was abolished by the PPARc inhibitor GW9662. Moreover, genetic ablation with small interfering RNA (siRNA), as well as pharmacological inhibition of PPARc decreased the cannabinoid-induced cell death and apoptosis. Likewise, GW9662 totally blocked the antitumoral action of cannabinoids in xenograft-induced HCC tumors in mice. In addition, PPARc...

Anxiety and related disorders are the most common mental conditions affecting the North American population. Despite their established efficacy, first-line antidepressant treatments are associated with significant side effects, leading many afflicted individuals to seek alternative treatments. Cannabis is commonly viewed as a natural alternative for a variety of medical and mental health conditions. Currently, anxiety ranks among the top five medical symptoms for which North Americans report using medical marijuana. However, upon careful review of the extant treatment literature, the anxiolytic effects of cannabis in clinical populations are surprisingly not well-documented. The effects of cannabis on anxiety and mood symptoms have been examined in...

Marijuana is the most widely used illicit substance in those diagnosed with bipolar I disorder. However, there is conflicting evidence as to whether marijuana may alleviate or exacerbate mood symptomatology. As bipolar disorder and marijuana use are individually associated with cognitive impairment, it also remains unclear whether there is an additive effect on cognition when bipolar patients use marijuana. The current study aimed to determine the impact of marijuana on mood in bipolar patients and to examine whether marijuana confers an additional negative impact on cognitive function. Twelve patients with bipolar disorder who smoke marijuana (MJBP), 18 bipolar patients who do not smoke (BP),...

Abstract In an increasing number of states and countries, cannabis now stands poised to join alcohol and tobacco as a legal drug. Quantifying the relative adverse and beneficial effects of cannabis and its constituent cannabinoids should therefore be prioritized. Whereas newspaper headlines have focused on links between cannabis and psychosis, less attention has been paid to the much more common problem of cannabis addiction. Certain cognitive changes have also been attributed to cannabis use, although their causality and longevity are fiercely debated. Identifying why some individuals are more vulnerable than others to the adverse effects of cannabis is now of paramount importance to public...

Cannabis is the most commonly used illicit substance among pregnant women. Human epidemiological and animal studies have found that prenatal cannabis exposure influences brain development and can have long-lasting impacts on cognitive functions. Exploration of the therapeutic potential of cannabis-based medicines and synthetic cannabinoid compounds has given us much insight into the physiological roles of endogenous ligands (endocannabinoids) and their receptors. In this article, we examine human longitudinal cohort studies that document the longterm influence of prenatal exposure to cannabis, followed by an overview of the molecular composition of the endocannabinoid system and the temporal and spatial changes in their expression during brain development....

Background: Our aim was to determine the combined and independent effects of tobacco and marijuana smoking on respiratory symptoms and chronic obstructive pulmonary disease (COPD) in the general population. Method: We surveyed a random sample of 878 people aged 40 years or older living in Vancouver, Canada, about their respiratory history and their history of tobacco and marijuana smoking. We performed spirometric testing before and after administration of 200 μg of salbutamol. We examined the association between tobacco and marijuana smoking and COPD. Results: The prevalence of a history of smoking in this sample was 45.5% (95% confidence interval [CI] 42.2%–48.8%) for marijuana use...

Background. Marijuana smoking is common and believed to relieve many symptoms, but daily use has been associated with liver fibrosis in cross-sectional studies. We aimed to estimate the effect of marijuana smoking on liver disease progression in a Canadian prospective multicenter cohort of human immunodeficiency virus/hepatitis C virus (HIV/HCV) coinfected persons. Methods. Data were analyzed for 690 HCV polymerase chain reaction positive (PCR-positive) individuals without significant fibrosis or end-stage liver disease (ESLD) at baseline. Time-updated Cox Proportional Hazards models were used to assess the association between the average number of joints smoked/week and progression to significant liver fibrosis (APRI ≥ 1.5), cirrhosis (APRI ≥...