Legalizing cannabis could offer promise for slashing opioid use, experts say

Leading medical experts say legalizing cannabis may offer new hope to one day reduce the use of opioids powerful drugs frequently prescribed for the treatment of pain.

Dr. Mark Ware, a globally recognized researcher and the vice-chair of the federal government's task force on legalizing marijuana, says a legal framework for cannabis will help to facilitate further research.

He said published scientific research already suggests cannabinoid molecules interact with the brain in a way that has an important "synergy" with how opioids interact with receptors in the body.

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"This appears to be a very profound affect," he said. "Research suggests there are important interactions between the two systems."

U.S. states that have legalized cannabis for medical purposes have also reported lower rates of deaths by opioid overdose, he added, noting what is lacking now is clinical studies to definitively say a patient on a high-dose opioid could use a cannabinoid to reduce their dose.

"That's the challenge we have to take this interesting possibility and explore it," Ware said.

Offering an alternative

Opioids have a limited role in successfully treating chronic pain disorders, he added, noting there may be a more expanded role for cannabinoid therapy to substitute for or potentially reduce opioid consumption.

The use of the powerful painkillers in Canada is second-highest in the world after the U.S. on a per-capita basis.

B.C. chief provincial health officer Dr. Perry Kendall agrees marijuana may offer a less dangerous alternative for people who are struggling with chronic pain.

"If you've got a lot of people taking high-dose opioids by prescription for a long period of time, if you start cutting them off, you really need to have off ramp or alternative to offer them," Kendall said in an interview.

"The pain societies across the country say we don't have that yet. ... Cannabinoids ... may offer one alternative."

Encouraging further research

Health Minister Jane Philpott said legalizing cannabis and opioid use are separate issues and that the potential harms and benefits of marijuana still need to be fully explored.

"Clearly Dr. Ware and many others are doing research in this area and we certainly encourage further research to better understand the realities," she said.

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The Liberal government is looking to have a legalized regime for recreational marijuana in place by July 2018 a move that will make Canada the first member of the G7 to legalize marijuana for recreational use across the country.

It tabled legislation in April that will, once passed, establish a "strict legal framework" for the production, sale, distribution and possession of cannabis, making it against the law to sell marijuana to youth.

The bill, which has now passed second reading in the House of Commons, proposes allowing adults 18 and over to possess up to 30 grams of dried cannabis or its equivalent in public, share up to 30 grams of dried marijuana with other adults and buy cannabis or cannabis oil from a provincially regulated retailer.