Cannabis-based medicines

What’s in cannabis-based medication? 

Cannabis-based medication has two primary active ingredients:  

  • Tetrahydrocannabinol (THC), which is psychoactive – meaning it alters mood, causing what’s known as a ‘high’ 
  • Cannabidiol (CBD), which is non-psychoactive, does not alter mood  

Whilst there is sufficient evidence to support the use of CBD medicines in the treatment of some complex childhood epilepsies, there is little evidence on the safety and efficacy of medicines which contain THC for the treatment of seizures in children

Who can be prescribed cannabis-based anti-seizure medication?  

Epidyolex (a pharmaceutically prepared CBD) is the only cannabis-based medicine that the NHS routinely prescribes and funds.  

It has been approved to treat seizures associated with Dravet syndrome, Lennox-Gastaut syndrome and Tuberous Sclerosis Complex.

Specialist doctors (paediatric neurologists) may also prescribe Epidyolex for other children with complex epilepsy. However, this is on a case-by-case basis, in exceptional circumstances where other treatments have not worked. 

The BPNA (British Paediatric Neurology Association) does not recommend prescribing unlicensed cannabis-based medicines (including those containing THC) for children with complex epilepsy.

A UK-wide Refractory Epilepsy Specialist Clinical Advisory Service (RESCAS) has been set up to provide advice and support to specialist doctors for the treatment of uncontrolled epileptic seizures. This includes consideration of treatments such as cannabis-based medicines. 

What about street cannabis?  

Cannabis-based medicines are not the same as street cannabis, which is illegal and has not been tested to make sure it is effective in the same way as licensed medicines. 

You should never attempt to use illegal cannabis as an anti-seizure medication. 

What about CBD products in shops, in cafes and online?  

CBD products are sold in shops, in cafes and online as food or food supplements, in products such as: 

  • Oils  
  • Drops or tinctures  
  • Gel capsules  
  • Sweets and confectionery  
  • Bread and other bakery products  
  • Drinks 

However, these products have also not been tested to make sure they are safe and effective in the same way as licensed medicine. 

The Food Standards Agency does not recommend CBD for children, or people taking any medication, unless under medical direction. This also applies to women who are pregnant, breast feeding or trying to conceive.


You can read more about cannabis-based medicines on the NHS website.

If you have any questions or concerns about cannabis-based medicines please speak with your consultant.

NB Young Epilepsy are currently reviewing our information portfolio which will be updated in October 2023.

Also in this section

More information about epilepsy

Epilepsy seizures

An epileptic seizure happens because of a disruption of the electrical activity in the brain

Epilepsy syndromes

A syndrome is a group of signs and symptoms which, if they occur together, can suggest a particular condition

Epilepsy & contraception

It is important that all teenagers are given information about the effects of AEDs on contraception and pregnancy before they become sexually active

Epilepsy & pregnancy

Some medication can have an effect on the development of the baby so it's important that you discuss planning a pregnancy with your consultant, epilepsy nurse or GP

Causes of epilepsy

The causes of epilepsy generally falls into three groups; genetic, structural/metabolic or unknown

Diagnosing epilepsy

Getting a diagnosis of epilepsy can often take some time. Only until there have been two or more seizures that a diagnosis of epilepsy will be considered