"There are risks of developing dependence upon cannabis", said Degenhardt. And yet, say the authors, they are being given to people with mental health problems in Australia, the U.S. and Canada, and demand is likely to grow.
Cannabis and cannabinoids are increasingly being made available for medicinal use in North America, Britain and Australia without being subjected to standard testing processes.
She continues: "In countries where medicinal cannabinoids are already legal, doctors and patients must be aware of the limitations of existing evidence and the risks of cannabinoids".
Cannabinoids, which include any chemical derived from the Cannabis plant that exerts drug-like effects in the body, "are often advocated as a treatment for various mental health conditions", according to the new analysis, published today (Oct. 28) in the journal The Lancet Psychiatry. Hardly any studies examined the effects of CBD or medicinal cannabis on the various disorders.More news: First Female UN High Commissioner For Refugees Chief Dies At 92
A team of Australian researchers analyzed the results of 83 prior studies that looked at medicinal cannabinoids' effects on mental health and neurological conditions, including depression, anxiety, Tourette syndrome, ADHD, PTSD and psychosis. Of the 83 studies, 42 looked at depression (including 23 RCTs), 31 looked at anxiety (17 RCTs), eight looked at Tourette syndrome (two RCTs), three were on ADHD (one RCT), 12 were on PTSD (one RCT), and 11 were on psychosis (six RCTs).
In most randomised-controlled trials of the effects of cannabinoids on depression and anxiety, the use was related to another condition, like chronic pain or multiple sclerosis. In the studies looking at the other four disorders, the cannabinoid was used to treat the mental health disorder. A growing number of states are legalizing it medicinally and recreationally; millions of people are vaping products that contain the compound THC (potentially to the detriment of their health); and non-psychoactive CBD is in everything from beauty products to seltzer water.
The new analysis pooled data from 83 studies aimed at learning whether medicinal cannabinoids can improve mental health disorders, overall, or alleviate their various symptoms. For example, recent research suggests that cannabis may reduce ratings of stress, depression, and anxiety, at first, but chronic use may worsen depressive symptoms over time.
It also increased the number of people who reported side effects, and the number who chose to withdraw from a study due to side effects.More news: Razer's Hammerhead wireless earbuds for gamers look like black AirPods
The study highlights the limited evidence and the low quality of the evidence that exists around using cannabinoids for treatment of mental health conditions. "One of the most striking things about the spread of legislation in multiple countries permitting cannabis/cannabinoids for medicinal purposes is that this is in many instances happening outside of the regulatory frameworks that medicine development typically occurs within", said Degenhardt, from the National Drug and Alcohol Research Centre at the University of New South Wales in Sydney.
Researchers emphasize the fact that more research that would directly examine the relationship between cannabinoids and mental health is needed.
Deepak Cyril D'Souza of Yale University School of Medicine in CT said cannabinoids should first be tested in randomized controlled trials and subjected to the same regulatory approval process as other prescription medications if they were to be used in the treatment of psychiatric disorders.
Dr. Scott Krakower, assistant unit chief of psychiatry at Zucker Hillside Hospital in Glen Oaks, New York, who was not involved in the study, told Live Science that the idea that cannabis may worsen certain mental health disorders is well-established.More news: EA Confirms No New Battlefield Until 2021