How safe is CBD for chronic pain?
Health & Fitness

How safe is CBD for chronic pain?

It’s now legal for adults “to cultivate, possess and consume cannabis for their private use”. 

Since it was decriminalised in September 2018, there has been increasing interest in the use of natural products to treat pain. It is still illegal to grow and sell cannabis in South Africa, although licences can be obtained to cultivate it for the export market. As Daily Maverick reported, it could potentially help in “promoting job creation and economic prosperity”.

Cannabis or dagga, as it is commonly known, is a collective name for the plant that consists of more than 100 compounds called cannabinoids. Two of the most known compounds in the plant are Cannabidiol (or CBD) and tetrahydrocannabinol (THC). CBD is non-psychoactive, whereas THC is the principal psychoactive compound. 

CBD is available in wellness shops and retail stores around the country, provided that it meets the threshold criteria of no more than 600 milligrams per sales pack. 

It is being marketed as a natural remedy for pain, insomnia and anxiety. Categorised as a homoeopathic product, CBD is unregulated and currently not controlled by the South African Health Products Regulatory Authority (SAHPRA). This might allow unscrupulous suppliers to sell unsafe products because they don’t have to show proof of what they contain. 

Dr Michelle King, a psychiatrist and current President of PainSA, says there is a surge in the use of cannabis and CBD products for treatment of pain. A 2022 study called “Changes in self-reported cannabis use in the United States from 1979 to 2022” published in 2024, found that for the first time, Americans were more likely to use cannabis daily than alcohol.

Sport enthusiasts and even some parents use it, believing that it is a preferred natural alternative. 

Read more in Daily Maverick: The good life: An 80-year study explains what could make you happy and healthy

Despite the growing hype, clinical trials have recently questioned the efficacy and safety of CBD and cannabis. The Journal for Pain published a study in April 2024 that found that CBD for pain was ineffective, expensive and possibly harmful. 

Cannabis and chronic pain

The International Association for the Study of Pain concluded that there wasn’t sufficient evidence to recommend medical cannabis for pain relief.

Dr Roland van Rensburg, a specialist clinical pharmacologist, says evidence of clinical trials should be seen in context. 

The cannabinoid content in the plants varies greatly; this makes it difficult to give a strong recommendation for or against cannabis for pain relief. However, the known possibility of cannabinoids causing harm, needs to be weighed up against the current results. 

Despite the latest conclusion that there was not sufficient quality evidence to endorse it, this doesn’t necessarily mean it is ineffective. 

More reliable studies are needed to reach a definitive conclusion and should ideally include the lived experiences of individuals who use cannabinoids for pain.  

Prof Sean Chetty, executive head of the Department of Anesthesiology and Critical Care at Stellenbosch University, has a special interest in pain management. 

He believes that despite the adverse findings of the CBD trials, the dosage of CBD sold in mainstream shops and pharmacies is insufficient to have any significant therapeutic effect. Professor Chetty also says that if something works for you, you should stick with it unless it is harmful. 

Based on his understanding of the legislation, the dosages currently being sold legally are probably not sufficient to be therapeutically active. 

Dr King says that treating chronic pain is complex. 

What works for one may not be the best solution for another. Problems might also arise if patients buy cannabis on the black market; this could be dangerous because customers do not know what percentage of THC and chemicals it contains.   

Placebo effect in treating chronic pain

The role of placebo in chronic pain management is very real and shouldn’t be underestimated. 

Studies show that about 50–60% of a patient’s experience of pain treatment is determined by placebo. 

A patient’s positive expectancy usually improves their response to pain. Other factors that can trigger a placebo response include the clinician’s attitude towards the treatment, a patient’s trust and relationship with the healthcare professional, prior experiences of pain treatment, the price of the medication — in fact, some people might believe that an expensive medication is more effective than a cheaper alternative — and opting for a brand name as opposed to using a generic.

How do CBD and placebos reduce pain?

Professor Chetty explains an individual patient’s response to chronic pain treatment happens on more than one level. 

CBD and THC trigger the body’s natural cannabinoid receptors that influence the pain experience. They set off a complex process that reduces the transmission of pain and has an analgesic effect. Placebos could set off a similar process that brings pain relief. 

Dr King advises that people living with chronic pain need to make an informed decision about the risks and benefits before deciding whether to go the conventional or alternative route. DM