“Medical cannabis” is a broad term for any sort of cannabis-based medicine used to relieve symptoms.

Many cannabis-based products are available to buy online, but their quality and content is not known. They may be illegal in the UK and potentially dangerous.

Some products that might claim to be medical cannabis, such as CBD oil or hemp oil, are available to buy legally as food supplements from health stores. But there’s no guarantee these are of good quality or provide any health benefits.

Specific cannabis-based products are available on prescription as medicinal cannabis. These are only likely to benefit a very small number of patients.

Can I get a prescription for medical cannabis?

Very few people in England are likely to get an NHS prescription for medical cannabis.

Currently, it is only likely to be prescribed for the following conditions:

• children and adults with rare, severe forms of epilepsy
• adults with vomiting or nausea caused by chemotherapy
• people with muscle stiffness and spasms caused by multiple sclerosis (MS)

It would only be considered when other treatments were not suitable or had not helped.

Epidyolex for children and adults with epilepsy

Epidyolex is a highly purified liquid containing CBD (cannabidiol).

CBD is a chemical substance found in cannabis that has medical benefits.

It will not get you high, because it does not contain THC (tetrahydrocannabinol), the chemical in cannabis that makes you high.

Epidyolex can be prescribed by a specialist for patients with Lennox-Gastaut syndrome and Dravet syndrome (both rare forms of epilepsy).

Nabilone for chemotherapy patients

Many people having chemotherapy will have periods where they feel sick or vomit.

Nabilone can be prescribed to adults by a specialist to help relieve these symptoms, but only when other treatments have not helped or are not suitable.

Nabilone is a medicine, taken as a capsule, that has been developed to act in a similar way to THC (the chemical in cannabis that makes you high). You may have heard it described as a “manmade form of cannabis”.

Nabiximols (Sativex) for multiple sclerosis (MS)

Nabiximols (Sativex) is a cannabis-based medicine that is sprayed into the mouth.

It is licensed in the UK for adults with MS-related muscle spasticity that has not got better with other treatments.

Read more from the MS Society on Sativex for treating muscle stiffness and spasms

Long-term pain

There is some evidence medical cannabis can help certain types of pain, though this evidence is not yet strong enough to recommend it for pain relief.

In some cases, however, it may be prescribed for pain as part of a clinical trial.

What about products available to buy?

Some cannabis-based products are available to buy over the internet without a prescription.

It’s likely most of these products – even those called CBD oils – will be illegal to possess or supply. There’s a good chance they will contain THC, and may not be safe to use.

Health stores sell certain types of CBD. However, there’s no guarantee these products will be of good quality.

They tend to only contain very small amounts of CBD, so it’s not clear what effect they would have.