She says price and challenging access schemes in states like Tasmania remain the biggest barriers preventing people suffering from getting their hands on the treatment.

"We are hearing anecdotally that Tasmanians are using services on the mainland outside of the Controlled Access Scheme," Ms Cleaver said.

"On the mainland in most jurisdictions any doctor can apply for their patient, GPs and the like. Where as in Tasmania you have to use a specialist."

Because state governments on the mainland often did not heavily subsidise the cost of medicinal cannabis, the cost of getting scripts filled was prohibitive, Ms Cleaver said.

"They're looking at getting one or two prescriptions and not being bale to afford it... some are saying it's $500 a month or even more than that," she said.

"There are thousands of people across the country breaking the law because they either can't get a legal prescription or they can get it and they can't afford it.

"It's evident that schemes across the country are overwhelmingly not working for the patient. People are running to the black market because they're hearing everywhere 'cannabis is good for this, cannabis is good for that' but they can't get it."