Doctors divided on medicinal cannabis

The move to increase access to medicinal cannabis is dividing doctors, and specialists say there's no evidence it reduces pain.

Within two years, New Zealand grown and produced medicinal cannabis could be available from the pharmacy.

But the GPs who will prescribe it are taking a tentative approach about the way it will work in practice.

Royal New Zealand College of General Practitioners president Dr Tim Malloy says many doctors have patients who want to try medicinal cannabis.

"In that we want to do the best for our patients, we would like to look at those opportunities, provided there was the appropriate framework to offer that."

He says the subject has divided those in the medical field.

"I think you'll find that there is quite a variation in opinion around on the matter across the country. A lot of that's to do with the perceived or otherwise lack of evidence around medicinal cannabis."

Medicinal cannabis is already available on prescription in New Zealand. However, experts like Dr John Alchin from the University of Otago say there's little or no evidence it works.

"It's not a silver bullet, we all wish there was a silver bullet for chronic pain," says Dr Alchin. 

"Most patients with chronic pain, we have no effective treatment for."

While cannabis may not reduce pain, it could have other effects.

"If people have high expectations, there's a placebo effect that comes in and a lot of people respond to a placebo," he says. 

"Especially with THC, it has a euphoric effect, so people may feel better."

So far, PHARMAC has declined to fund any medicinal cannabis products, but remains open to reviewing evidence.