Not your garden variety, 1970s weed: Sask. doctor warns of 'bad cannabis'

There’s good cannabis, and there’s bad cannabis, says a Regina doctor — and young people in particular should know the difference. Dr. Senthil Damodharan says cannabis now is much more damaging and toxic than it used to be.

Psychiatrist says impact of cannabis on developing brain can't be understated

The future of the first cannabis retail store in Thunder Bay, Ont. remains up in the air as the city and others await a final decision by the Alcohol and Gaming Commission of Ontario. (Gosia Wozniacka/The Associated Press)

There's good cannabis, and there's bad cannabis, says a Regina doctor — and young people in particular should know the difference.

Dr. Senthil Damodharan, the head of child and adolescent psychiatry in Regina, said cannabis has been bred to create a better buzz, but that change has come with a drawback.

"Cannabis available now is is not the cannabis that was available back in the day," he said. "It's much more toxic and damaging to the developing brain and we have high quality research evidence to suggest that early onset [or] teenage use leads to long-term adverse outcomes."

Two of the natural compounds in cannabis are cannabidiol (CBD) and tetrahydrocannabinol (THC). THC is what causes the high

In the 1970s and 1980s, CBD content was roughly equal to THC content, he said. Now, the THC content hovers between 20 to 30 per cent and CBD content is typically around one per cent.

"The content of CBD really matters," he said.

Damodharan said CBD — what he called "good cannabis" — can help with anxiety or can even help with treatment in certain circumstances, for everything from seizures to psychotic disorders.

It can also protect the developing brain from the harmful effects of THC, he said.

Dr. Senthil Damodharan says teenagers should know about the damaging impacts of cannabis on the developing brain. (CBC News)

He said research shows cannabis use among young adults can impact reasoning, judgment, memory and learning. It can also impact or increase the risk of psychosis.

"What we know is if there's a family history of mental illness, there's a higher risk that young people in that family will show adverse outcomes, like psychosis, anxiety and depression," he explained.

"Psychosis is the most important mental health outcome we're all worried about."

Damodharan says now with the legalization of marijuana, youth are getting "confused messages" that cannabis use is acceptable.

But governments, teachers, doctors and other role models have a social responsibility to make it clear to teenagers and young adults about the potential impact of cannabis use on the developing brain, he said.

"If they want to be a social cannabis smoker later in life, they should delay use of cannabis as much as possible, well into their late teens, ideally into the early twenties."


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