British Columbia

This 420, consider the potency of cannabis you use, says doctor

420 is this weekend, and while many will be partaking of the newly legalized cannabis, a Vancouver doctor is urging participants to consider regulating the potency of the products they use. 

Doctor recommends high CBD, low THC products

THC and CBD are the two chemical compounds in cannabis. (David Donnelly/CBC)

The pot festival 420 is this weekend, and while many will be partaking of the newly legalized cannabis, a Vancouver doctor is urging participants to consider regulating the potency of the products used.

Dr. Launette Rieb, a family physician, researcher and addiction medicine specialist, says since legalization, she has seen an increase in people experimenting with and using cannabis regularly. She's also noticed many are using products that have a higher potency than ever studied before. 

"I think most people get their information from the Internet or from their bud tender or their licensed producer," Rieb told Gloria Macarenko, host of On the Coast.

"Though many are quite knowledgeable and have information, I haven't yet found a patient that [has had] their supplier go over some of the negative side effects."

Potency

THC and CBD are the two chemical compounds in cannabis products. Rieb says in the 1960s and 70s, cannabis was about three per cent THC and CBD, a low potency, and was a balance of both compounds. 

Now, in B.C., the average potency of THC in cannabis products is 20 to 25 per cent, says Rieb. And people can buy products — marijuana concentrates — that are as high as 95 per cent THC.

"It's always good to go in and have a chat with your doctor if you're considering use for various conditions, even for recreational use."

"I haven't yet found a patient that [has had] their supplier go over some of the negative side effects," said Dr. Launette Rieb. (Jeorge Sadi/CBC)

Risks

THC is the addictive substance in cannabis, and high potency can be risky, says Rieb. High potency can result in psychosis and THC can cause increased anxiety and panic, even though many believe they smoke cannabis to help with that. THC also often creates heart palpitations, hallucination, paranoia and can be memory impairing, says Rieb.

Rieb said so far researchers have not found CBD to be addictive, and it will not cause psychosis. 

"In fact there's some studies that are small but indicate that it may possibly be protective against psychosis, especially THC-induced psychosis."

Rieb said CBD at very high doses is shown to reduce seizure frequencies and reduce pain, It should not be used on it's own, but should be used at a higher potency than THC. 

"[Choose] a low THC, high CBD product and use it sparingly and beware of your dose escalation. Vaporize instead of smoke."

Listen to the full story here:

April 18, 2019 Dr. Launette Rieb is a family physician and drug researcher who has concerns about the potency of marijuana products. 9:33

With files by On the Coast.