This article originally appeared on VICE UK.

Since last Thursday, medical cannabis has been legal in the UK. This means specialist doctors are now able to prescribe cannabis products for conditions where there is a proven medical benefit, potentially helping thousands of people suffering from severe forms of epilepsy, multiple sclerosis (MS), chronic pain, and nausea as a result of chemotherapy, among other ailments.

This landmark change in the law occurred after several stories came to light of sick children suffering under prohibition, including Billy Caldwell. The severely epileptic 12-year-old hit headlines earlier this year when the Home Office confiscated the Canadian-bought cannabis oil that made his condition manageable. Nationwide horror at the situation prompted Home Secretary Sajid Javid to order a review of the law, after which it was decided that cannabis should be changed from a Schedule 1 drug (no medical value) to a Schedule 2 (can be prescribed).

But let's be clear: The struggle is far from over. The NHS released its prescription guidelines last week and they were disappointingly restrictive. Drawn up by the Royal College of Physicians and the Royal Paediatric Neurology Association, the guidelines say cannabis products can only be used as a last resort, and that patients with MS and chronic pain are unlikely to get prescriptions. In fact, the guidelines state baldly that: "Very few people in England are likely to get a prescription for medical cannabis."

An MS Society statement said: "It's likely that nothing will change in the short-term for the one in ten people who get relief from pain and muscle spasms by using medical cannabis. We're calling for the interim guidance of prescribing medical cannabis to be urgently reviewed so that access to the treatment isn't so restricted."

Jon Liebling, Political Director of the United Patients Alliance (UPA), said of the guidelines: "When you read them, you get the feeling they haven't put much thought into this other than to protect themselves from having to take on the entire responsibility and accountability for introducing an entire new classification of medicines." Although, to be fair, he added, the organizations drawing up these guidelines were given no more than three months for this gargantuan task.

Despite the limited scope laid out in the guidelines, Health Secretary Matt Hancock seemed to imply that doctors are being given a certain level of flexibility. He said: "Doctors need to use their clinical judgment, and having guidance in place helps. Ultimately, the need to treat an individual person and the responsibility for that falls on the shoulders of a doctor—that's what they do." Indeed, there will be no direct policy from government that limits the conditions for which medical cannabis can be prescribed.

That said, it's unlikely that many doctors will want to stick their necks out and go against the guidelines of their professional body. "The Royal College of Physicians has spoken, and the vast majority of physicians will capitulate to that because it is their professional responsibility," said Liebling. "Until those guidelines loosen up, it is going to be incredibly difficult for anyone to get a medical prescription for a cannabis product."

This is compounded by the fact that the UK has almost no medical professionals properly trained in this kind of medicine. Cannabis has been outlawed for so long that doctors have never had to consider it before, nor does their medical training contain anything about its therapeutic use. The lack of knowledge among physicians means they are even more likely to heavily rely on the prescription guidelines provided.

Billy Caldwell and his mother Charlotte actually flew to Canada again last week to seek new treatment, as Billy's seizures were starting to reappear. Epilepsy patients treated with cannabis oil can start to "plateau" when the exact makeup of the cannabinoids in their medicine needs changing. The expertise needed to tackle this is not available for Billy in the UK.

Charlotte said: "Billy's doctor in Belfast—while she's been incredibly supportive—is not an expert, so she has to be cautious in writing a new prescription in medicine she is not trained in. We need the expertise—we need our doctors trained and educated. That's one of reasons we have had to leave the country."

The NHS guidelines also suggest that children with rare, severe forms of epilepsy should be treated with epidiolex, which is a product containing the cannabinoid CBD, but no THC. Charlotte says this is always the first step in treatment, as it was for Billy, but he is two years in and epidiolex will not work for him now.

She said: "This is my little boy. This is his medicine and his life, so I have to be sure I am doing the right thing by him. There is no medical cannabis product available for Billy. I had no other choice but to put him on a plane and bring him to Canada for an urgent evaluation. Now, I can't bring him home on the new legislation because the guidelines are really restricting what doctors can do."

The good news is that there should be new guidelines relatively soon. The National Institute for Clinical Excellence (NICE) have been given until October, 2019 to produce full guidelines for the prescription of medical cannabis products to replace the current, somewhat rushed, interim guidelines. The UPA has been approved as a stakeholder, meaning patients will be consulted; Liebling is optimistic that these guidelines will have a greater scope.

The struggle is not over for patients, but the dam has been broken. What seemed impossible a year ago has happened in the space of just a few months, but it will take some time to thrash out the details. It's so important to get those right when progress happens this way—little by little, then all at once.

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