High-strength cannabis linked to addiction and mental health problems
“76% increase in people entering treatment for cannabis addiction in the past decade.”
“…the safest level of use for cannabis is of course ‘no use’..” Kat Petrilli, Doctor of Philosophy, Bath University
Largest ever study into the health effects of different types of cannabis highlights concerns about stronger forms of the drug.
- Press release - Last updated on Tuesday 26 July 2022
The new systematic review from Kat Petrilli and Tom Freeman (Psychology) is published in The Lancet Psychiatry.
As the strength or potency of cannabis products has increased internationally over the years, so have rates of people being treated for cannabis addiction, say the authors of a new study.
Researchers from the Addiction and Mental Health Group at the University of Bath (UK) systematically analysed the relationship between the types of cannabis people use and their addiction and mental health problems. Their work draws on 20 studies involving almost 120,000 people.
After alcohol and nicotine, cannabis is the most widely used drug globally. Latest estimates from the UK suggest that over the last year around one in five 16-24 year olds had used cannabis.
Cannabis potency refers to the concentration of tetrahydrocannabinol (THC) in cannabis - the key psychoactive drug it contains. Recent studies from the same team at Bath have found that the concentration of THC in cannabis has increased significantly over time meaning that cannabis used today is typically much stronger than previously.
The new study, published in The Lancet Psychiatry, suggests that people who use high potency cannabis are more likely to experience addiction than those using low potency products. It also suggests that people using high potency cannabis are more likely to experience a psychotic disorder, such as schizophrenia.
These findings may help to explain why more people have received treatment for cannabis problems over recent years. Data from the European Monitoring Centre for Drugs and Drug Addiction show a 76% increase in people entering treatment for cannabis addiction in the past decade.
Lead author, Kat Petrilli from the University of Bath’s Department of Psychology explained: “Our systematic review found that people who use higher potency cannabis could be at increased risks of addiction as well as psychosis when compared to people who use cannabis products with lower potencies.
“These results are important in the context of harm reduction which aims to minimise the negative consequences associated with drug use. While the safest level of use for cannabis is of course ‘no use’, it is important to acknowledge that a significant number of people across the world use cannabis regularly and to ensure they can make informed decisions that could reduce any possible harms associated with it.”
The full paper 'Association of cannabis potency with mental ill health and addiction: a systematic review’ is available via https://www.thelancet.com/journals/lanpsy/article/PIIS2215-0366(22)00161-4/fulltext.
(Source: https://www.bath.ac.uk/announcements/high-strength-cannabis-linked-to-addiction-and-mental-health-problems/ )