Hero photograph
Photo by Dan Goofy

A growing problem

Lesley Brook —

Regular cannabis use by adolescents is associated with poor mental health.

In New Zealand adolescents are the age group most likely to use cannabis. It is being portrayed positively in the media and in music, and there is a perception that it is safer than tobacco. However, there is increasing evidence to suggest that regular cannabis use can have negative effects on mental health, particularly for adolescents.

Nursing student Lucy Melchert reviewed the literature and found that adolescents who have used cannabis between 10 to 50 times are three times more likely to develop schizophrenia than non-users, probably due to permanent changes to the brain from repeated exposure to THC. There is also a strong relationship between frequent use of cannabis and development of mental health issues such as depression, anxiety and suicidal thoughts.

Lucy recommends that the best way to decrease cannabis use amongst adolescents would be a school-based educational programme, targeted at 12 to 16-year-olds and delivered by health professionals and/or people with personal experience of drug abuse. The programme should focus on the effects that cannabis use can have on day-to-day life including relationships with friends and family. To be most effective such a school-based programme should be supported by a media campaign, to reduce cannabis use amongst adolescents and improve their mental health.