The family of an eight-year-old girl who stopped having seizures after taking medicinal cannabis has called for a meeting with Tasmania's Health Minister.

The young girl's mother is frustrated by the Government's conservative stance on the drug, and wants the Minister Michael Ferguson to see the results first hand.

Alice Agnew has a rare genetic condition with no known cause.

Her mother Nicole Cowles said without treatment, the condition was debilitating.

"By the time she was 28 weeks of age she was having 30 seizures a day and we were told she was going blind and dying," she said.

Twice a day, Alice takes medicinal cannabis orally in liquid form which is sourced from interstate.

Ms Cowles said it is the only drug that helps reduce her seizures.

Earlier this month the Tasmanian State Government turned down an offer from Tasman Health Cannabinoids (THC) to run trials in conjunction with the University of Tasmania.

Mother says ministers 'haven't done their research'

The State Opposition today launched a petition, supported by Ms Cowles, to have the Government's ban on medicinal cannabis reversed.

The petition was launched by shadow attorney-general Lara Giddings.

"When you see how the life of someone like Alice has been turned around through the use of medicinal cannabis, it's a hard man who looks into the eyes of the mother, Nicole, and says 'No, you can't have this drug'," she said.

Ms Cowles said she believes momentum for the medical use of cannabis has shifted.

"I don't think my daughter's health should be limited by a small number of politicians who maybe haven't done their research," she said.

But Parliamentary Secretary to the Premier, Guy Barnett, said the Government will not change its mind on the issue.

"The Government's position is very clear, a decision has been made and that it is for health and safety reasons and for a range of other reasons that the Government doesn't support a trial," he said.

"In all the other states of Australia it has also been made clear that this is not on the table."

Ms Cowles has invited the Mr Ferguson and other government ministers to see the results of medicinal cannabis first hand.

"I'd love them to meet Alice I think they might be quite surprised," he said.

THC's chief executive Troy Langman said the company is still looking to set up the trials.

"What we've seen in the past is once decision makers become educated... and they can see the tremendous results then and the life changing results they are changing their positions," he said.

In a statement, Mr Ferguson said the proposal for the medicinal cannabis trial involved looking at its effectiveness in reducing nausea for chemotherapy patients.

The Minister said it did not include testing the drug for treating pain or epilepsy in children and he would be happy to meet Ms Cowles to discuss the subject.

A Legislative Council committee will hold hearings on the issue next month.