There is no evidence that CBD products reduce chronic pain, and taking them is a waste of money and potentially harmful to health, according to recent research, which also found that some of these products might contain chemicals other than CBD, and be toxic.
CBD (short for cannabidiol) is one of many chemicals found naturally in the cannabis plant. It has become a popular alternative treatment for pain and is readily available in shops and online in the form of oils, tinctures, vapes, topical creams, edibles (such as gummy bears) and soft drinks.
However, consumers would do well to steer clear of these products, said the study team, which has called for chronic pain to be taken more seriously.
“CBD presents consumers with a big problem,” said Professor Chris Eccleston, who led the research from the Centre for Pain Research at the University of Bath. “It’s touted as a cure for all pain but there’s a complete lack of quality evidence that it has any positive effects.
“It’s almost as if chronic pain patients don’t matter, and that we’re happy for people to trade on hope and despair.”
For their study, published in The Journal of Pain, the team – which also included researchers from the Universities of Oxford and Alberta in Canada – examined research relevant to using CBD to treat pain and published in scientific journals up to late 2023.
They found, among other things, that CBD products sold directly to consumers contain varying amounts of CBD, from none to much more than advertised; that of the 16 randomised controlled trials delving into associations between pain and pharmaceutical-grade CBD, 15 showed no positive results, with CBD being no better than placebo at relieving pain; and meta-analysis linked CBD to increased rates of serious adverse events, including liver toxicity.
Medical vs non-medical CBD
In the UK, medical cannabis is the only CBD product that is subject to regulatory approval. It's occasionally prescribed for people with severe forms of epilepsy, adults with chemotherapy-related nausea and people with multiple sclerosis.
Non-medical CBD is freely available in the UK (as well as in the US and many European countries) so long as it contains negligible quantities of THC or none at all. However, CBD products sold on the retail market are not covered by trade standards, meaning there is no requirement for them to be consistent in content or quality.
Most CBD products bought online, including popular CBD oils, are known to contain very small amounts of CBD. Moreover, any given product may be illegal to possess or supply, as there’s a good chance it will contain forbidden quantities of THC.
Chronic pain
An estimated 20% of the adult population lives with chronic pain, and sufferers are often desperate for help to alleviate their symptoms. It’s no surprise then that many people reach for CBD products, despite their high price tag and the lack of evidence of their effectiveness or safety.
Dr Andrew Moore, study co-author and former senior pain researcher in the Nuffield Division of Anaesthetics at the University of Oxford, said: “For too many people with chronic pain, there’s no medicine that manages their pain. Chronic pain can be awful, so people are very motivated to find pain relief by any means. This makes them vulnerable to the wild promises made about CBD.”
He added that healthcare regulators appear reluctant to act against the spurious claims made by some manufacturers of CBD products, possibly because they don’t want to interfere in a booming market (the global CBD product market was estimated at US$3bn in 2021 and is anticipated to reach US$60bn by 2030) especially when the product on sale is widely regarded as harmless.
“What this means is there are no consumer protections,” said Moore. “And without a countervailing body to keep the CBD sellers in check, it’s unlikely that the false promises being made about the analgesic effects of CBD will slow down in the years ahead.”
The study’s authors are calling for chronic pain to be taken more seriously, with consumer protection becoming a priority.
“Untreated chronic pain is known to seriously damage quality of life, and many people live with pain every day and for the rest of their lives,” said Eccleston. “Pain deserves investment in serious science to find serious solutions.”
Study details
Cannabidiol (CBD) products for pain: ineffective, expensive, and with potential harms
Andrew Moore, Sebastian Straube, Emma Fisher, Christopher Eccleston.
Published in The Journal of Pain on 18 October 2023
Highlights
• Cannabidiol (CBD) products have varying amounts of CBD, from none to much more than advertised.
• CBD products may contain other chemicals than CBD, some of which may be harmful.
• Sixteen RCTs for pain used pharmaceutical CBD in oral, buccal/sublingual, and topical forms.
• Fifteen of the 16 RCTs were negative: no greater pain-relieving effect for CBD than for placebo.
• Meta-analyses link CBD to increased rates of serious adverse events and hepatotoxicity.
Abstract
Cannabidiol (CBD) attracts considerable attention for promoting good health and treating various conditions, predominantly pain, often in breach of advertising rules. Examination of available CBD products in North America and Europe demonstrates that CBD content can vary from none to much more than advertised and that potentially harmful other chemicals are often included. Serious harm is associated with chemicals found in CBD products and reported in children, adults, and the elderly. A 2021 International Association for the Study of Pain task force examined the evidence for cannabinoids and pain but found no trials of CBD. Sixteen CBD randomised trials using pharmaceutical-supplied CBD or making preparations from such a source and with pain as an outcome have been published subsequently. The trials were conducted in 12 different pain states, using three oral, topical, and buccal/sublingual administration, with CBD doses between 6 and 1,600 mg, and durations of treatment between a single dose and 12 weeks. Fifteen of the 16 showed no benefit of CBD over placebo. Small clinical trials using verified CBD suggest the drug to be largely benign; while large-scale evidence of safety is lacking, there is growing evidence linking CBD to increased rates of serious adverse events and hepatotoxicity. In January 2023, the Food and Drug Administration (FDA) announced that a new regulatory pathway for CBD was needed. Consumers and healthcare providers should rely on evidence-based sources of information on CBD, not just advertisements. Current evidence is that CBD for pain is expensive, ineffective, and possibly harmful.
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FDA working to regulate the cannabidiol ‘cure-all’ deluge
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