What have we learned about the adverse health effects of cannabis use in the past 20 years?


Wayne Hall

(The University of Queensland Centre for Clinical Research)

This paper discusses what research has shown about the adverse health effects of cannabis in the past 20 years. In 1994 there were very few epidemiological studies of the health effects of cannabis and the literature was dominated by (1) animal studies of the toxicity, teratogenicity and mutagenicity of cannabis and THC and (2) human laboratory studies on the effects of daily cannabis use over to 7 to 35 days on the health of college students. Since then epidemiological studies have been reported on the effects of regular cannabis use in adolescence and young adulthood on psychosocial outcomes in the late 20s and early 30s. The most informative of these studies have of New Zealand birth cohorts, a large enough proportion of whom used cannabis regularly for long enough to inform us about the possible adverse effects of regular use. The New Zealand findings have been supported by cohort studies in Australia, Germany and the Netherlands. In the paper, I compare the conclusions reached on the adverse effects of acute and chronic cannabis use in 1994 with the inferences that can now be reasonably draw in the light of evidence that has accrued over the past 20 years.

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If anyone would like to read a full copy of the paper please contact Ingrid James

Wednesday, 12th February 2014, 12.45-2.00pm
Venue: LG4, Tavistock Place