Families left in cannabis catch 22 one year after medicinal use made legal in the UK

• Video report by ITV News Science Editor Tom Clarke

One year ago, a change in the law allowed doctors in the UK to prescribe medicinal cannabis.

Those eligible to receive the treatment range from children with severe epilepsy to those with sickness from chemotherapy to those with MS.

The law change should have meant the drug was available on the NHS - but families are still having to pay out of their own pocket to purchase it as the service won't pay for it.

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Fallon's family are just one of the many struggling with the financial burden of buying the life changing drugs.

Her seizures are life threatening and his mother, Elaine, is running out of money to buy the medicinal cannabis that contains them.

She told ITV News: "For a bottle like this, privately prescribed in the UK, would cost me £670 a bottle.

"My daughter uses one of these bottles every two and a half days, which I don't think anyone can afford.

"What I do is get a flight and I travel to Amsterdam where I can get it for £170.

"I've tried to raise money for funds, I've got my house on the market, I've got one month's medicinal cannabis left - after that I don't know what I'm going to do."

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Part of the issue with the NHS supplying the drug is because it is unlicensed, more data needs to be collected on it.

That's something one clinic in London's Harley Street hopes to change.

It's the only one in the UK prescribing cannabis.

Lorna Bland says its already helping her chronic pain: "There's a limited number of people who can afford to come down this route. I am very lucky that I can. Data will be collected on me, which ultimately will benefit the patients who are not in a position to access their medicine of choice," she told ITV News.

Patient groups and some clinicians argue drugs based on cannabis plant extract show the most promise for treating epilipsy and other conditions like chronic pain and PTSD.

NICE, which approves drugs, says there's not enough evidence it works. But until more patients are taking it, there won't be enough evidence.

For now that leaves patients relying on cannabis in a Catch 22.