Health Canada has ordered a Vancouver doctor to stop treating addicts with a psychotropic substance that he claims "saves lives."

Dr. Gabor Maté, a physician who has worked in Vancouver's Downtown Eastside, has been using the Amazonian plant brew ayahuasca to treat individuals with drug addictions.

The substance, he says, induces "sometimes visionary states, sometimes just strong emotions, sometimes just physical sensations, which help people experience something of their deepest feelings."

He says he's been administering ayahuasca in a safe, secluded context, and that it saves lives by allowing people to confront past traumatic events.

"It's putting it very simply, but it's just an experience that allows people to get to know themselves and accept themselves more deeply," he says.

In a letter dated Nov. 4, Health Canada demanded Maté stop using ayahuasca to treat addiction without a license or proper authorization. Ayahuasca contains three substances restricted under Canada's Controlled Drugs and Substances Act.

The letter states that according to the act, "anything that contains a controlled substance is also a controlled substance."

"If you do not immediately cease all regulated activities with controlled substances, we will contact, within 30 days of this letter, the Royal Canadian Mounted Police for enforcement action as they deem necessary," it states.

Maté says he was surprised by Health Canada's "very strict interpretation" of the regulation. He says he's not using a purified or refined form of the plant, but the plant itself.

He adds that his own work as well as international studies on ayahuasca have convinced him of its effectiveness, and that he will pursue an exemption in order to continue working with it.

"I don't need any more proof as to its safety or as to its value, I just need the opportunity to work with it without fear of legal sanction," he says.

A documentary chronicling Maté's work with ayahuasca, "The Jungle Prescription," will air Nov. 10 at 8 p.m. on the CBC program The Nature of Things. Also that day, Maté will be interviewed on CBC Radio's The Current.

Robyn Smith reports and edits for The Tyee.