Does smoking cannabis lead to anxiety?

A new study has found that nearly one-third of people who visited the hospital emergency room (ER) for a cannabis-related concern developed a new anxiety disorder within three years, Fortune reported.

The study was published in The Lancet's open-access journal, Eclinical Medicine, and is considered to be the most comprehensive research conducted linking the use of cannabis and anxiety.

The research conducted in Canada involved the examination of the health records of more than 12 million people between 2008 and 2019 who had never shown signs of anxiety.

The study discovered that those who visited the ER for cannabis use during that time were almost three times more likely to receive a new anxiety disorder diagnosis within three years. 

They were also nine times more likely to later need medical attention for an anxiety illness.

According to the study, young male cannabis users aged between 10 to 24 years were most vulnerable to anxiety.

After Michigan legalised cannabis in 2018, research released in April 2023 in Cureus found that the drug's psychological impacts were causing a rise in ER visits.

Researchers discovered that throughout two years, nearly 20% of ER visits at an undisclosed state hospital resulted in a diagnosis of cannabis-induced anxiety.

"Cannabis use has rapidly increased in Canada over the past 15 years, and there is a general sense that cannabis is relatively harmless or has health benefits. Our study cautions that in some individuals, heavy cannabis use may increase their risk of developing anxiety disorders," says Dr Daniel Myran, research chair at the University of Ottawa.