Medical cannabis available on the NHS: what you need to know

Cannabis-based medications can now be prescribed by doctors for certain conditions following new government policy introduced last week.

Meanwhile, CBD oil is another cannabis-derived product that is booming in popularity as a health supplement.

There is some confusion about what these products are for, their legal classification and what's next for medical cannabis in the UK.

We answer some common questions below, including what the differences are between medical cannabis and CBD oil supplements and who can access them legally, with input from Royal Pharmaceutical Society spokesperson Aileen Bryson.

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Medical cannabis: what is it and what is it used for?

Medical cannabis refers to any cannabis-based medication, of which there are various forms from dried plant matter to tinctures. These are currently used to treat a limited range of conditions, often in cases where alternatives haven't worked.

Some of these medicines contain the derivative cannabidiol (CBD), but not tetrahydrocannabinol (THC), which is the psychoactive chemical in cannabis that creates a 'high'.

There are also man-made compounds designed to act in a similar way to THC (such as Nabilone).

Can I get a prescription for medical cannabis?

Most people will not be able to get a prescription for medical cannabis.It is currently only likely to be prescribed for:

• children with rare, severe forms of epilepsy (Lennox-Gastaut syndrome and Dravet syndrome)
• people with spasticity from MS, which isn't helped by other treatments
• people with vomiting and nausea caused by chemotherapy

NHS guidancestates that a decision to prescribe cannabis products would only be considered where other options had been exhausted first.

It also says that, while there is some evidence medical cannabis can help certain types of pain, the evidence is not strong enough to recommend it as a treatment for pain relief at present.

How do you get a prescription if you qualify under the new rules?

Prescriptions for medical cannabis will not be available from GPs, and will need to be given by a hospital specialist consultant upon referral.

The NHS emphasises that if you do not have a child with one of the rare forms of epilepsy that might be helped by medical cannabis, or the other conditions listed above, you should not request a referral from your GP.

Will medical cannabis become legal in the UK?

The Home Secretary and the NHS have both said that these new measures are in no way a path to legalisation for recreational use. They do however consider the possibility of more cannabis-derived medical treatments being available eventually.

The Royal Pharmaceutical Society (RPS) welcomed the new measures and has suggested that more research into these products, and their potential use for other ailments, could now take place.

Royal Pharmaceutical Society spokesperson Aileen Bryson said:'The recent review conducted by the Chief Medical Officer in England concluded that there are medicinal benefits from cannabis, particularly in areas such as chronic pain, nausea and vomiting caused by chemotherapy, some rare forms of epilepsy and the spasticity of multiple sclerosis.'

'However, more research is needed to identify which parts of the plant are producing the most benefits and to minimise side effects, as well as to identify optimal doses and give quality assurance.'

CBD oil: what is it, and what's it used for?

CBD oil is a cannabis-derived product that's available to buy legally without a prescription. It's made from the liquid extracted from hemp, which is then mixed with other substances such as olive or coconut oil to create the end product.

It has been on the rise in 2018 as the hot new 'wellness' supplement. Holland & Barrett started stocking legal CBD oil earlier this year and has reported a surge in popularity. It's also started turning up in everything from cosmetics to coffee pods.

Is CBD oil legal?

Most cannabis-derived products are controlled substances under the Misuse of Drugs Act, but some types of CBD oil are legal to sell as health supplements.

CBD oils approved for sale in the UK must not contain more than 0.2% of THC, the chemical responsible for the 'high' effect.

What are the health benefits of CBD oil?

Various studies have suggested that CBD oil in differing forms and concentrations may:

• provide pain relief
• alleviate anxiety
• clear up acne
• reduce inflammation
• ease nausea.

However, evidence at this stage is not robust. A World Health Organisation report earlier this year noted that the research into CBD oil as a treatment for these conditions was not advanced.

RPS spokesperson Aileen Bryson explained: 'In Britain cannabis oil (CBD) is sold as a food supplement and is not licensed as a medicine. To be sold legally these products should not be making any claims for health benefits.'

The NHS website states that Epidiolex, a CBD-based medicine, is currently going through the licensing process. In the meantime, it can be prescribed in certain circumstances for children with rare forms of epilepsy, as described above.

What are the side effects of CBD?

Aileen Bryson told us: 'Side effects will vary depending on the dose and product used. Products from other countries will contain very different levels of both CBD and THC.'

'There is still a lack of available long-term safety data, but the most common side effects from CBD seem to be tiredness, diarrhoea and changes in appetite.'

The NHS warns against buying supplements online, as there is no way of knowing if they are safe. It also warns that CBD can affect how other medicines work, so you should talk to your GP before taking any supplements.

Can I travel with medical cannabis or CBD oil?

The rules differ by country, so you'll need to check before you travel.

Tommy Lloyd, managing director of travel insurance comparison website Medical Travel Compared, says: 'You could get a fine, or go to prison, if you travel with medicines that are illegal in another country. Travellers are advised to check with the embassyof the country they are hoping to visit first to understand any restrictions on entry, or routine testing for drugs, as CBD and THC can remain in the body for several days or weeks after use.'

He warns that you may need to show proof at the border that you are using cannabis for medicinal purposes, and advises that patients request a signed letter from the consultant who prescribed your medicine. Extra clearances will be required if you're travelling for more than three months.