Hundreds of doctors from around the world are in Boston this week for the International Conference on Opioids, a three-day event to educate medical professionals on how to effectively treat patients without contributing to the opioid epidemic. Some consider medical marijuana to be an effective alternative to conventional prescription drugs for treating pain. Dr. Mark Ware, an associate professor in family medicine and anesthesia at McGill University in Quebec, Canada, is a keynote speaker at the conference and spoke with WGBH's Morning Edition anchor Joe Mathieu about alternative methods for pain management. The following transcript has been edited for clarity.

Joe Mathieu: I wonder, as someone who has studied cannabis — and there are not a lot of them in our country — how effective you see it in treating pain compared to opioids prescribed by doctors?

Dr. Mark Ware: I think there are probably two quick ways to answer that question. One is that we know opioids are tremendously good analgesics for acute pain — post-operative pain, trauma. And cannabinoids really are not. The active ingredients in cannabis, THC, cannabidiol, really don't appear to be good in acute pain settings. Where they do appear to play an important role is in chronic pain. When someone's had pain for more than six months, there are some important changes in their spinal cord, in their brains. Receptors for cannabinoid molecules start to increase in number, and this makes people, we think, more responsive to potentially the analgesic effects of cannabinoids with chronic pain, and, in particular, pain which is caused by nerve injury — neuropathic pain. So trauma to a nerve, either centrally, like the case of multiple sclerosis or stroke, or where the disease affects the peripheral nerves, like diabetes or shingles. And it appears to be something to be considered, not as a first-line therapy but when other conventional therapies have not been successful.

Mathieu: Would marijuana be consumed by smoking it or would that be edible marijuana in the scenario that you're describing?

Ware: So cannabis, historically, and probably rather classically, has been thought of as a smoked drug, but there are now emerging very novel and very important ways of consuming the cannabinoid molecules that don't involve smoking. And this could be vaporization, which is a very interesting technology that heats the plant to a temperature where the cannabinoid oils come off in a gas form but doesn't burn the plant material and therefore have some of the nasty side effects of inhaling burnt smoke. And then, of course, there are oral administrations, so especially here in Canada where our legal industry is producing oils where they extract the cannabinoids from the plant into an oil base, and that can be taken in food or under the tongue. And so I think there's an increasing interest in non-smoked methods of delivery, and those seem to be just as effective in managing pain as the inhaled route.

Mathieu: We have legal recreational marijuana here in Massachusetts and retail sales are about to begin in July. I wonder if doctors like yourself are worried about people self-medicating when they hear about news like this.

Ware: I think people have been self-medicating for a long time. And I think where doctors need to start to engage is to insist upon some form of quality control. So what patients, if they choose to use this, that they know what it is they're using, they know how strong the dose is, and this is really where cannabis needs to go. We need to have standardized measures of what is in these products, so that a doctor and patient can have an informed discussion about how much they should use. And this of course requires an investment in research to better understand dose and dose response.

Mathieu: Dr. Ware, marijuana is one path that we're talking about here, I wonder how many other alternatives there are for pain management?

Ware: I think probably the best way to break out of the loop of classical pain management is to avoid the reliance on pharmacotherapy and cannabis is included in this. I think where that field is going and needs to continue to go is in adopting access to non-pharmacological methods: psychotherapy approaches, mindfulness, meditation approaches, physical therapy, exercise, yoga, tai chi, these are all therapies that have evidence-based efficacy and effectiveness in managing chronic pain. And arguably where it needs to go is a combination of these approaches. So you're not just using a pill to treat your pain, you're also learning that you have to undertake some behavior changes. You have to increase your activity and your exercise, all within the constraints of the problem. But it's that combination, that integrated approach, that I think is going to be the answer, and not a reliance on pharmacology.

Editor's Note: Dr. Mark Ware has consulted for companies developing cannabis therapies and he will soon make the transition into the private sector to work for one of Canada’s largest cannabis therapy companies.
This story has been updated.