Barcelona snapshots

Prof. Sir Robin Murray

Sir Robin Murray psychiatrist Controversies Psiquiatry Barcelona
Insitute of Psychiatry, King's College London, United Kingdom
Talk Can we prevent psychosis? Cannabis use: the most important target
Date Thursday, September 16th, 2021
Time 19:00 - 19:45
Round Table 2. Addictions


Robin Murray is Professor of Psychiatric Research at the Institute of Psychiatry, Psychology and Neuroscience, Kings College, and indeed has spent most of his working life there apart from one year at NIMH in the USA. His particular interest is in psychosis. He was one of the first to suggest that schizophrenia was in part a neurodevelopmental disorder, and he and his colleagues have contributed to the understanding that environmental factors such as obstetric events, drug abuse and social adversity dysregulate striatal dopamine and thus increase the risk of psychosis. He also cares for people with psychosis at the South London and Maudsley NHS Trust. He has written over 800 articles, not all of them boring! He is the most frequently cited psychosis researcher outside the USA, has supervised 72 PhDs and 12 MD Theses, and 40 of his students have become full professors. He was elected a Fellow of the Royal Society in 2010 and received a knighthood in 2011.


Evidence from medicine shows that the best way of preventing a disorder is to persuade the general population to avoid exposure to risk factors; for example, the campaign against tobacco smoking and its effect on lung cancer. Much epidemiological evidence demonstrates that cannabis use is associated with increased risk of subsequent onset of psychosis. Our work shows a) a dose-response relationship between the level of use and the risk of later psychosis; b) that continued use by those with established psychosis is associated with a worse outcome, and c) experimental administration of tetrahydrocannabinol (THC), the active ingredient of cannabis, induces transient psychosis in normal subjects. Our Trans~European study of 16 sites in 6 countries demonstrates that daily use of high potency cannabis has a significant impact on the incidence of psychosis. The greatest effects were in the cities where high potency cannabis was most available, Amsterdam and London, where 50% and 32% respectively of first episode cases of psychosis could be attributed to daily use of high potency cannabis. The evidence that regular use of (especially high potency) cannabis has a major effect on the incidence of psychosis is now sufficient to support for public health messages outlining the risk. Furthermore, the findings that decriminalisation and legalisation are associated with increased use and potency, suggest that the incidence of psychosis is likely to increase without such public educational campaigns.