Writing in today’s Irish Examiner, Dr Bobby Smyth, a lecturer in public health at Trinity College Dublin and consultant child and adolescent psychiatrist in the HSE’s Adolescent Addiction Service, said some people would benefit from access to medicinal cannabis, including MS sufferers and those with Dravet’s Syndrome.

But he said decades of research “indicate that cannabinoids is either wholly or largely ineffective for most disorders” and he referred to the increased potency of cannabis and its role as “the dominant substance causing young people to seek addiction treatment across Ireland”.

“Many of the young people who attend our services are quite politicised regarding cannabis, talking about it with a quasi-religious fervour. It’s not just something they do, it’s how they define themselves.”

Referring back to issues associated with so-called ‘head shop’ drugs which were subsequently made illegal, he wrote: “It seems that we have an unusual enthusiasm for intoxication in Ireland. This is an extra reason to be wary of expanding the menu of intoxicants.”

He said there is evidence that cannabidiol can have a profound impact on reducing seizures in a minority of children with Dravet’s Syndrome, but while it can be legally prescribed in Ireland, it is “via a cumbersome route for both doctor and patient”.

“It would be great to come up with a legislative method which would ensure that other evidence-based medicines which might contain some THC [Tetrahydrocannabinol] could also be prescribed by prudent doctors,” he said.

On the bill, brought by People Before Profit TD Gino Kenny, Dr Smyth said: “While its declared intentions are admirable, this is a crazy bill.”

Mr Kenny said there would be amendments at committee stage but added: “The pros far outweigh the cons.” He rejected any suggestions of the bill being a Trojan horse and said it was focussed on medicinal use, while adding: “We have to have a debate on decriminalisation of drugs in this country. That debate will happen next year or the following year.”

Vera Twomey, who has led a campaign on behalf of her young daughter Ava, who has Dravet’s Syndrome, for regulated access to cannabidiol, said: “Everybody is entitled to concerns but it’s not fair to suggest that the bill is worthless.

“It’s vital to be able to discriminate between people smoking cannabis and people, responsible parents, accessing cannabidiol for purely medicinal purposes.”

Ms Twomey said that Ava, who is using cannabidiol, has had three seizures so far in December, whereas previously three in 45 minutes was not unusual. She also cited a report published earlier this year in the UK by Prof Mike Barnes which called for legalised access to medical cannabis as a matter of urgency. “There are aspects of the bill that Gino Kenny is more than happy to work on,” she added.