Cannabinoid (cannabis) oil: information for families

This information sheet from Great Ormond Street Hospital (GOSH) describes the approach we take to cannabinoid (cannabis) oil. This information does not apply to Epidiolex® a prescribed cannabinoid medication for complex epilepsy. 

Everyone at GOSH recognises that parents / carers only wish to do the best for their children. This sometimes involves using complementary and/or alternative medicines and therapies. There has been significant media attention recently, focused on the use of ‘natural’ chemicals extracted from the cannabis plant. These chemicals are extracted into oil and are collectively known as cannabinoid oil (also known as cannabis oil).

As clinicians, we value the open and honest discussion with parents / carers about the use of cannabinoid oils and actively encourage all parents and carers to discuss this difficult subject with us. Despite the extreme importance of families informing staff of administration of cannabinoid oil, we are currently in the difficult position of not being able to support administration. 

GOSH will continue to work closely with the government and national bodies to ensure that we are always up to date with research evidence, national policy and licensing regulation. 

There are different types and concentrations of cannabinoid oils, some of which are currently illegal. 

In circumstances where we become aware that a child is being given cannabinoid oils with a THC content of more than 0.2 per cent (%), a member of the hospital social work team WILL be asked to review the situation. 

In circumstances where we become aware that a child is being given cannabinoid oils with a THC content less than 0.2 per cent (%), a member of the hospital social work team MAY be asked to review the situation. 

This will be in order to assess and consider any risks and whether the matter requires referral to local children’s services team to consider potential safeguarding issues with the relevant authorities. 

We appreciate that this places parents / carers in an extremely challenging position but assure you that the matter will be handled as sensitively as possible, ensuring that at all times we put ‘the child first and always’. 

What is cannabidiol and what are cannabiniod oils? 

The cannabis plant is very complex and is thought to contain over 100 different cannabinoids. Current focus falls on use of two specific cannabinoids found in cannabis:

  • Delta-9-tetrahydrocannabinol (THC) – main psychoactive component
  • Cannabidiol (CBD) – non-psychoactive component 

Epidiolex® is a pharmaceutically-prepared cannabidiol product that has been examined in clinical trials in the UK, Europe and USA, and has been shown to be effective in reducing seizures in two forms of rare epilepsy, Dravet Syndrome and Lennox-Gastaut Syndrome. The data is currently with the regulatory authorities here in Europe and in the USA for consideration of licensing as a medicine. Some children are on this product prescribed by paediatric neurologists. 

Cannabinoid oils available either in the UK or internationally over the internet or in health food stores, at present, may contain CBD alone in varying strengths, THC alone in varying strengths or may contain a combination of both and other cannabinoids in varying ratios. Legality of the cannabinoid oils available is discussed below but may vary across international borders. Formal testing has shown that what it says on the bottle is not always reliable as there may be no quality assurance testing. 

What are the legal issues of buying and/or using cannabinoid oil? 

In the UK, cannabis derived products containing more than 0.2 per cent (%) THC are considered illegal unless it holds authorisation from the Medicines and Healthcare Products Regulatory Authority (MHRA). MHRA authorisation for medicinal use of a chemical or drug requires the drug to demonstrate safety and benefit in well designed, randomised studies usually against placebo (dummy therapy) or current gold standard therapy, as well meeting stringent pharmaceutical quality standards. 

Cannabinoid oils advertised as containing CBD but less than 0.2 per cent (%) of THC are available in the UK from various outlets (online and on the high street). These products are legal, if sold for the purpose of being a ‘health food supplement’ for oral ingestion (taking by mouth) or as a ‘beauty product’ when sold in cream form, and NOT sold for any purported curative or medicinal effects. 

Despite being sold as ‘health food supplements’, these CBD-containing oils still contain active substances with the potential to interfere with other prescribed medication. The nature of these interactions may be to EITHER make prescribed medication less active OR more toxic. 

What is the risk of taking cannabinoid oil? 

While widely circulated communications suggest cannabinoid oils are safe and do not interfere with other medication, in reality, investigations have shown real interference with any anti-epileptic drugs metabolised (broken down) by the liver. We have also had experience of cannabis oils interfering with strong pain killers. Most routinely used medications have not yet been tested in combination with cannabinoids. There is a potential risk for interaction with regularly prescribed medications for other conditions. 

Known side-effects of cannabinoids determined from clinical trials include sedation, appetite suppression, diarrhoea, dizziness and abnormal liver function. 

We have no real information on the side-effect profile of cannabinoid oils, especially in young children, who may be extremely sensitive to small doses. In addition, young children are often unable to accurately describe adverse effects meaning toxicity may be under reported. 

There is no information on the long-term effects of cannabinoids. 

Is Cannabinoid oil available on the NHS? 


There are limited patients prescribed the cannabidiol drug (Epidiolex®) who are continuing treatment following clinical trials. 

If I want to use cannabinoid oil with 0.2 per cent (%) of THC or less, will GOSH provide it or allow me to use it? 

While we recognise that these products are available and not illegal, we will not provide them for your child. Our recommendation is for these products not to be given to children, given the potential for interference with regularly prescribed medication as well as the limited available safety data relating to children. 

For these reasons, GOSH has decided that we currently cannot have non-prescribed cannabinoid preparations on hospital premises. Where we discover that this product is on GOSH premises, we will ask that you remove it as soon as possible and discuss it with the consultant responsible for the care of the child. 

Compiled by: 
Alison Steele and the GOSH Safeguarding, Social work, Palliative care and Pharmacy teams.
Last review date: 
October 2018


This information does not constitute health or medical advice and will not necessarily reflect treatment at other hospitals. If you have any questions, please ask your doctor. No liability can be taken as a result of using this information.