CBD oil: miracle cure or snake oil?

What is CBD oil?

The cannabis plant, Cannabis sativa, contains a number of active ingredients, including THC and CBD. THC (tetrahydrocannabinol), the most active ingredient of marijuana, is the component that makes a person high when either smoked or ingested. Cannabidiol (CBD), on the other hand, is not psychoactive: it doesn’t induce a mind-altering effect.

CBD oil is a way of delivering CBD. This chemical is first extracted from the plant and then diluted with a carrier oil like hemp seed. It can then be consumed as either the oil itself or within drinks or confectionary. In the UK, it can be found in health shops.

How does CBD work?

The human body has two currently-known types of points where cannabinoids can bind, called CB₁ and CB₂ receptors. Cannabinoids can attach to the CB₁ and CB₂ docking points since they have a similar structure to the body’s naturally-occurring endocannabinoids. From here, CBD can impact movement, pain, emotions, mood and other functions regulated by endocannabinoids. This is still an area of active research and much of how it all works is still being explored.

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Is CBD Legal?

The vast majority of cannabinoids, listed as controlled substances under the Misuse of Drugs Act, are illegal.

However, CBD derived from industrial hemp that is EU-approved is completely legal in the UK, under certain conditions. The strain must contain no more than 0.2 per cent THC, and the THC must not be easily separated from it. By contrast, cannabis oil, which has a higher THC content, is not legal.

With the change of law in November 2018, specialist clinicians are allowedto prescribe cannabis-derivedmedicinal products for some patients with multiple sclerosis or epilepsy. However, cannabis-derived products including CBD oils available to buy over the internet are unlikely to meet the required standards, making them illegal and potentially dangerous.

Is CBD oil effective?

Many users of CBD oil claim it helps to relieve pain and inflammation, reduce anxiety and make them calm. Currently, scientific studies cannot say whether the small CBD quantities available in CBD products have any effect at all, but that hasn't held back use. This is an area of ongoing research - we just haven't reached a point where we have all the answers. Science is working to catch up with the demand.

CBD products available in health food shops and on the internet are not controlled or regulated as medicines, other than the legal limit on THC content. As doctors, we are advised to tell patients that ‘over-the-counter or internet’ CBD products lack quality assurance and should not be treated as medicines. There’s no way to be sure of what’s in the products you buy.

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What conditions can CBD oil help?

The list of things we’re told CBD oil can do for us is long, but there is still only preliminary evidence.

There is some belief that CBD is a natural painkiller. It’s also thought to have anti-inflammatory properties, and so it may help as a treatment for inflammatory diseases like Crohn’s disease. Indeed, some small studies in mice have supported this claim by showing that CBD significantly reduced chronic inflammation and pain. This has led hope that it may one day help chronic pain, but we won’t know until human tests are complete.

CBD is also believed to help people who suffer from anxiety and mood-related symptoms, as well as insomnia.

The condition that brought CBD oil to prominence is epilepsy. Scientific reviews have found that CBD has anti-seizure properties and there are several clinical trials well underway, some of which use pure CBD product. Stronger forms of CBD have been found to reduce the number of epileptic seizures suffered by some patients by more than 40%.

This has resulted in parents of children suffering with severe epilepsy buying illegal forms of high-strength cannabidiol CBD oil online. But this carries risk.

Initial research in mice published in the Journal of Alzheimer's Disease found that CBD may one day help people in the early stages of the condition by helping them keep the ability to recognise the faces of people that they know. Undoubtedly the impact of cannabis-based treatment on Alzheimer’s is an exciting new, promising area. Researchers from the National Institute for Health Maudsley BRC are conducting a study to see if cannabis-based treatment containing CBD can ease symptoms of agitation and aggression in patients with Alzheimer’s, where at the moment treatment options are limited. Still, it’s early days.

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