PUFFING THE PAIN AWAY

Study looks into safety of medicinal marijuana

The McGill University Health Centre is participating in a pioneering
scientific study on the effects of medical marijuana use.

Since 2001, the Canadian Medical Marijuana Access Regulations have granted
patients with severe pain and certain other symptoms access to cannabis for
medical purposes. Today, 10 to 15 per cent of Canadians suffering from
chronic pain legally use cannabis as an analgesic.

However, the medical community knows little about the possible long-term
effects that regular cannabis use might have on patients with pain. For
instance, these patients often take other medications such as pain relievers
and antidepressants, but the interaction between those drugs and marijuana
has not yet been scientifically investigated.

"We need much more information on the safety issues facing these patients,"
said Dr. Mark Ware, a physician at the MUHC Pain Centre.

Ware also heads the MUHC branch of the "Cannabis for the Management of Pain:
Assessment of Safety Study," also known as COMPASS. This clinical trial
follows 1,400 chronic pain patients at eight different sites across Canada,
350 of whom will use cannabis as part of their pain-alleviation regimen. He
and the MUHC COMPASS site will follow 200 pain patients, 50 of whom will use
cannabis.

COMPASS participants suffer from "hard-to-treat neuropathic or muscle pain,
such as spinal cord injuries, multiple sclerosis, and arthritis," said Ware.

They will be steadily monitored for one year and then periodically assessed
over two years.

The researchers will be on the lookout for a range of safety issues such as
damage to kidney, liver, heart, and lung functions, as well as any adverse
cognitive effects.

"A chief goal of the study is to determine how marijuana interacts with
other chemicals," said Ware. "The participants will be instructed to
continue taking their prescription or over-the-counter painkillers and
antidepressants."

The COMPASS study is the first of its kind, both nationally and
internationally. Ample research has been conducted in the past concerning
the effectiveness of marijuana as an analgesic, but never before has anyone
attempted to investigate its safety as used for medical purposes.

One question this study raises is whether the Canadian government will move
to broaden public access to this type of treatment if the results of the
study indicate that marijuana use for pain is safe. As the moment, only
those Canadians who meet very specific medical criteria may legally use
marijuana.

Moreover, eligible candidates for medical marijuana must be vetted by the
federal government before they can be supplied with the drug. These
stringent rules make it difficult for pain patients to gain access to
government-issued cannabis, and some wonder if the COMPASS study could quell
apprehension about the drug and contribute to a Canadian health care regime
in which marijuana is available at the local pharmacy.

Marc Boris, leader of the Canadian Marijuana Party, conceded that while such
a state of affairs is unlikely in the near future, scientific proof that
marijuana is safe to use for medical purposes might inspire politicians to
consider cannabis and other herbal treatments as viable alternatives or
complements to chemical drugs on a more mainstream level.

Dr. Paul Cleland of the Montreal General Hospital approves of the pain study
but does not share Boris's view.

"If physician discretion becomes the only mechanism in place, there will
likely be instances of abuse," he said. "Free and legal marijuana is an
appealing idea to many, so we must be cautious about how it's dispersed."

The study begins this week. Dr. Ware and his research team are not presently
in search of new recruits - the MUHC COMPASS site was bombarded with over
500 phone calls from interested pain sufferers since the project was
publicized in mid-December.