What 20 years of research on cannabis use has taught us:
- In the past 20 years recreational cannabis use has grown tremendously
- Almost as common as tobacco use among adolescents and young adults, and so has the research evidence.
A major new review in the scientific journal Addiction sets out the latest information on the effects of cannabis use on mental and physical health.
The key conclusions are:
Adverse Effects of Acute Cannabis Use
- not fatal overdoses
- doubles risk of MVA if intoxicated
- use during pregnancy slightly reduces birth weight
Adverse Effects of Chronic Cannabis Use
- Regular cannabis users can develop a dependence syndrome the risks of which are around 1 in 10 of all cannabis users and 1 in 6 among those who start in adolescence.
- Double risks of psychotic symptoms and disorders (especially if they have a personal or family history of psychotic disorders, and if they start using cannabis in their mid-teens)
- Regular adolescent users:
- lower educational attainment
- more illicit drug use
- produce intellectual impairment
- doubles risk of schizophrenia
- higher risk chronic bronchitis.
Cannabis smoking by middle aged adults probably increases the risk of myocardial infarction.
