There is a high prevalence of cannabis use reported in non-affective psychosis. Early prospective longitudinal studies conclude that cannabis use is a risk factor for psychosis, and neurochemical studies on cannabis have suggested potential mechanisms for this effect. Recent advances in the field of neuroscience and genetics may have important implications for our understanding of this relation...

BACKGROUND Governmental debate in Ireland on the de facto decriminalisation of cannabis and legalisation for medical use is ongoing. A cannabis-based medicinal product (Sativex®) has recently been granted market authorisation in Ireland. This unique study aimed to investigate Irish general practitioner (GP) attitudes toward decriminalisation of cannabis and assess levels of support for use of c...

Cannabis is the most widely used and variably regulated drug in the world, with increasing trends of use being reported in the US, Australia, Asia, and Africa. Evidence has shown a decrease in the age of commencement of cannabis use in some developed countries and a prolongation of risk of initiation to cannabis use beyond adolescence among more recent users. Cannabis use is associated with num...

BACKGROUND Anxiety reactions and panic attacks are the acute symptoms most frequently associated with cannabis use. Understanding the relationship between cannabis and anxiety may clarify the mechanism of action of cannabis and the pathophysiology of anxiety. Aims of the present study were to review the nature of the relationship between cannabis use and anxiety, as well as the possible clinica...

Cannabis users are more likely to have psychotic experiences (PEs). The degree to which these associations are driven by genetic or environmental influences in adolescence is unknown. This study estimated the genetic and environmental contributions to the relationship between cannabis use and PEs. Specific PEs were measured in a community-based twin sample (4830 16-year-old pairs) using self-re...

AIM To examine possible causal linkages between cannabis use and psychosis using data gathered over the course of a 25-year longitudinal study. DESIGN A 25-year longitudinal study of the health, development and adjustment of a birth cohort of 1265 New Zealand children (635 males, 630 females). SETTING The Christchurch Health and Development Study, a general community sample. PARTICIPANTS ...

OBJECTIVE Cannabis is the most commonly used illicit substance in the United States and is increasingly being legalized throughout the United States. Many believe that cannabis is relatively harmless, and some believe that cannabis is not addictive. We wondered what the rates of cannabis abuse and dependence might be among adolescents referred for substance use evaluations and also about the in...

AIMS To examine changes in the evidence on the adverse health effects of cannabis since 1993. METHODS A comparison of the evidence in 1993 with the evidence and interpretation of the same health outcomes in 2013. RESULTS Research in the past 20 years has shown that driving while cannabis-impaired approximately doubles car crash risk and that around one in 10 regular cannabis users develop d...

BACKGROUND Cannabis use is associated with an earlier age at onset of psychotic illness. The aim of the present study was to examine whether this association is confounded by gender or other substance use in a large cohort of patients with a non-affective psychotic disorder. METHOD In 785 patients with a non-affective psychotic disorder, regression analysis was used to investigate the indepen...

OBJECTIVE Cannabis is the most commonly used illicit drug in developed nations. In adolescent girls especially, rates of cannabis use have increased over the last decade, urging the need to characterize the potential correlates of onset of cannabis use during emerging adulthood. METHOD Using data from 1065 females (collected 1994-2005) who participated in both the baseline and follow-up wave ...