There are about 4,000 legally registered users of marijuana in Canada. (Canadian Press)

Canada's first International Medical Marijuana Expo in Toronto hopes to attract people suffering from health problems who are "sick and tired of taking pharmaceutical drugs that have adverse side-effects," says the event's organizer.

The event, which is being held in the Metro Toronto Convention Centre this weekend, is labelled as "the first expo promoting the respectable and responsible use of marijuana as medicine."

The expo's website says it will feature a number of vendors who are selling products "who specialize in the medicinal use and production of high-quality medical marijuana."

Marco Renda, who is organizing the expo, said he expects well over 30,000 visitors, including many from the United States and Europe.

Marijuana will not be available at the expo, although registered medical users are welcome to bring cannabis to smoke in a marijuana vaporization room, he said.

'We're not trying to promote: "Come down to the convention centre and get stoned." This isn't what it's all about.'— Marco Renda, organizer of the Expo

Vaporization is a process in which hot air is pushed through a chamber containing marijuana. That air is then pushed into a separate chamber, and then inhaled.

"Vaporization is a way of using cannabis in a healthier mode because there's no combustion," said Renda, who is a registered grower of marijuana. He is also a registered user of the drug, which he uses to mitigate symptoms of hepatitis C.

"We're not trying to promote: 'Come down to the convention centre and get stoned.' This isn't what it's all about. This is about educating yourself on the benefits of cannabis as medicine."

More action from government urged

The medical use of marijuana is permitted in Canada, although there's a lengthy process involved to obtain the drug from Health Canada.

People who want to use marijuana legitimately must submit a detailed application for authorization and include two photos. Their doctor must also fill out a medical form that spells out why the applicant's medical condition satisfies the conditions for an authorization.

Depending on the nature and severity of the illness, the doctor will be asked to spell out that conventional therapies failed or were medically inappropriate.

Renda also hopes to boost awareness about medical marijuana.

"Less than two per cent of the licensed cannabis card holders in Canada actually buy the medicine from the government," he said, adding that many users get the drug from so-called compassion clubs. He said government investment in the growth of medical marijuana is inadequate.

"There's only one strain that Health Canada is providing," said Renda, adding there are over 1,600 different strains of marijuana.

"There isn't one pill in the pharmacies — so how can one strain of cannabis help with all these various ailments? It can't. It needs to be treated as a proper herbal medicine."

As of June 2009, there are just over 4,000 registered medical marijuana users in the country.