Not all medicinal marijuana is created equal. That's what some experts are saying as they warn about the health risks and curtailed effectiveness associated with smoking medicine.
As medical pot becomes increasingly mainstream and Canada moves toward legalising the substance, health experts are emphasising the need for doctors and patients to consider the sometimes serious side effects linked to the various ways of consuming the drug.
Paul Farnan, an addictions specialist at the University of British Columbia, likened a recommendation to smoke medicinal marijuana to a doctor handing out a prescription to light up an opium pipe.
"We know there's something in opium that helps pain, and we're able to pharmaceutically develop morphine and other analgesics, but we wouldn't say to people, 'You have pain? Why don't you smoke opium?' '' he said.
"We're kind of saying to people, 'We think there's some stuff that cannabinoids will be helpful for. Why don't you just smoke cannabis?' First of all, cannabis is actually a really dangerous thing for your lungs.''
Mikhail Kogan, medical director of the Centre for Integrative Medicine at George Washington University in Washington, D.C., said he sees no reason for people to smoke marijuana medically anymore.
It's difficult to absorb enough of the drug through the lungs, and gastric acids interfere when someone eats it, he said, adding that it's more effective to take the drug by other means, such as under the tongue.
"Rectally is actually a lot more preferred because of the volume of absorption. You can put a lot more and it gets absorbed a lot better, but not everybody is open to this way of administration,'' Kogan said.
"We have so many other products now, so many modes of delivery, that smoking in my opinion is very archaic and has very little clinical applicability,'' he added.
"Having said that, I think that probably the majority of people still smoke because it's the most available method.''
Health Canada officially recommends against smoking marijuana.
"Many of the chemicals found in tobacco smoke are also found in cannabis smoke,'' reads its website. The Canadian Medical Association has no formal position on the consumption of medicinal pot, but it officially opposes the inhalation of any burned plant material.
Association spokesman Jeff Blackmer added that many physicians are reluctant to prescribe medical marijuana because of the absence of peer-reviewed research into whether the drug is medically effective, its possible side effects, appropriate dosage and more.
A "strong majority'' of doctors would prefer not to be involved as so-called gatekeepers, Blackmer added. "Most of them hate it,'' he said.
"This is something that was imposed on us by the government and the majority of physicians do not want to have anything to do with it.''
Debra Lynkowski, head of the Canadian Lung Association, urged patients and doctors to take lung health into consideration when discussing medicinal marijuana. "When you burn something, that combustion releases toxins and carcinogens, and they're released regardless of what the source is,'' she said.
"Our primary concern with regard to that is just to be considering any kind of lung health implications.'' "We know that there's an issue with smoking. However, we can't control it at the patient level."
Colette Rivet, head of the association that represents licensed cannabis producers in Canada, said that while the industry is against smoking medical marijuana, ultimately it can't restrict what patients do. "
We know that there's an issue with smoking. However, we can't control it at the patient level,'' Rivet said. "We're trying to develop new product forms so they would be more inclined to go away from that.''
Each licensed producer has its own unique document that physicians fill out when prescribing medical marijuana, which includes a minimum amount of information required by Health Canada, Rivet said. Beyond that, some companies ask whether a patient would prefer dried marijuana or oil, while others don't, she added.
A Health Canada spokesman confirmed that patients are in charge of requesting the form of medical marijuana they prefer, whether dry leaf or oil, and they are not restricted in how they wish to consume it. The sale of edibles is banned, but a June 2015 decision from the Supreme Court of Canada ruled medicinal marijuana patients have the right to prepare their medication however they want, including cooking it.