In response to growing calls for cannabis to be legalised for people with certain illnesses, including children with intractable epilepsy, Victorian Health Minister David Davis said on Thursday that he would amend the Drugs, Poisons and Controlled Substances Act to make it easier for doctors to conduct clinical trials of medicinal cannabis. 

He would also consider removing a prohibition on the "cultivation of narcotic plants for therapeutic purposes in the context of approved clinical trials" and gave "in principle" support for Victorians to be part of an international trial of Epidiolex - a cannabis-based pharmaceutical being tested overseas in children with epilepsy. However, it is unclear when such a trial could begin. 

While the Victorian branch of the Australian Medical Association welcomed the government's approach, some doctors questioned what, if anything, would change given a cannabis pharmaceutical - Sativex - is already being used in clinical trials in Australia. Cancer patients at the Royal Melbourne Hospital have been receiving it in a clinical trial since 2012 to see if it eases difficult-to-treat pain. 

Leading psychiatrist Pat McGorry,  who is planning to trial a compound of cannabis thought to treat psychosis - cannabidiol (CBD) - said he did not know of any major barriers to conducting clinical trials of cannabis-based pharmaceuticals in Victoria. 

"My perception is that it should be possible already, especially if it's synthetic," Professor McGorry said.

President of the Australian Drug Law Reform Foundation and addiction medicine specialist Alex Wodak described the Coalition's announcement as "nonsense" and said: "It sounds good, but if you look at the small print, it's really nothing. This might benefit 10 people in Victoria in five years time".

While Sativex has been approved by the Therapeutic Goods Administration for the treatment of multiple sclerosis and is being tested in a small group of cancer patients in a clinical trial, Dr Wodak said it is very unlikely that doctors would prescribe the drug to others wanting it for other conditions for which it might be useful. 

Furthermore, an Australian National Council on Drugs report on medicinal cannabis published this week said that while pharmaceutical companies could continue to apply to the TGA for cannabis products to be used for particular conditions, approval takes a "significant length of time" and Australia's small market for such products may not offer sufficient incentive to manufacturers. 

Mr Davis' announcement follows Opposition Leader Daniel Andrews' election promise to legalise access to medical marijuana for Victorians with life-threatening conditions. Labor has vowed to instruct the Victorian Law Reform Commission to examine the prescription, manufacture and distribution of medical cannabis. But it remains unclear how the market for the product might be regulated under the plan.

Dr Wodak said both plans ignored more than 100 randomised controlled clinical trials showing that different forms of cannabis can treat chronic pain, muscle spasticity and nausea. Trials have also shown it can stimulate appetite in people with weight loss due to cancer or HIV. 

He said this evidence had been enough for countries such as the Netherlands to allow safe cultivation and prescription of cannabis-based pharmaceuticals to people, just like other medicines are prescribed.  

"I like the idea of emphasising research ... but it also delays the inevitable. We want medicinal cannabis now," Dr Wodak said. "Large numbers of people believe it is beneficial."  

On Thursday, The Age revealed that some Victorian families were buying vials of methylated spirits, alcohol and water, thinking it was medical cannabis. 

Mr Andrews said this highlighted the need for Labor's plan. 

"This confirms for me that there is an imperative to legalise and regulate the use of medical marijuana right across the state."

The debate came as Mullaways Medical Cannabis director Tony Bower - who supplies cannabis oil to more than 150 families - was sentenced to 12 months' jail in a NSW court on Thursday for cultivating cannabis.

Families who rely on the black market for cannabis oil to treat children with intractable epilepsy said they did not feel hopeful of sourcing the drug legally any time soon.

Cassie Batten, who gives a cannabis tincture oil to her toddler, Cooper, to prevent life-threatening seizures, said she did not believe clinical trials would help her family's situation, but wanted more detail. 

Ms Batten said because children responded differently to various combinations of tetrahydrocannabinol (THC) and CBD - two compounds found in cannabis - regulating one specific product may not help some people. 

"You get very different results," she said. 

Ms Batten said the side effects for existing prescription medications used to treat seizures could be horrific.