Back

Can cannabis cure cancer?

You are likely to have come across all sorts of health claims linked to the use of CBD oil, and potentially cannabis itself. But is this just another cancer myth, or could cannabis really cure cancer? The most important thing to know is that there is currently no scientific proof that cannabis, or any of the chemicals in cannabis, can be used to cure cancer. But it's an important topic to discuss, so we have looked into the current science to answer some of the top questions you might have on cannabis and its effect on cancer.

What is cannabis?

Cannabis is the name of a plant, originally from Asia, that contains cannabinoids that can affect how the brain works or relieve pain. It has been used for millennia for medicinal and recreational purposes.

What are cannabinoids?

Cannabinoids are a class of chemical compounds found in the cannabis plant
CBD is short for cannabidiol, one of the main cannabinoids found in cannabis
THC is another main cannabinoid, and the one that makes you 'high'
CBD oil is an oil containing CBD, and potentially other cannabinoids - but not THC (at least in the UK)

Is cannabis legal?

In the UK, cannabis is illegal to possess or supply for personal recreational use. Since 2018 its use has been legalised for some medical use, but it currently cannot be prescribed for cancer or pain. CBD and CBD oil can be sold and purchased legally.

Can CBD oil be used to treat cancer?

There is no evidence that CBD oil can be used to treat cancer in people. CBD does show promise for the management of some cancer related symptoms, including pain and anxiety, however more research into the appropriate amounts of CBD and its effects on humans is necessary.

Why have I heard about someone who was cured when they used CBD oil?

The problem with these stories, and any anecdotal evidence, is that it’s difficult to know whether you have all of the facts. It’s impossible to make any kind of judgement without knowing about the type of cancer, what other treatment was involved and the person’s medical history. This is why research and regulated clinical trials are so important. They enable us to make informed decisions on what treatments are likely to work best based on solid evidence.

Is CBD oil safe?

CBD oil is relatively safe. Side effects of CBD include nausea, fatigue and diarrhoea, but the doses sold in UK health stores are generally too low to cause any serious harm. Because CBD oil is freely available to purchase in stores, it is not as tightly regulated as medicines - and most importantly, it can affect certain medications, so you should always check with your GP before trying CBD oil.

Does CBD oil offer any medical benefits?

There is some evidence that CBD oil could be effective against some rare childhood epilepsies - but again, more data is needed before we can draw any firm conclusions. Studies also show that CBD oil could be beneficial for managing anxiety and insomnia in some people, and early research also suggests a possible use of CBD for the treatment of certain types of pain. As with all alternative and complementary therapies, our advice is always to consult with your doctor or another healthcare professional to make sure you are receiving the best treatment for your own needs.

What is the difference between CBD and THC?

THC and CBD are both found in the cannabis plant and have similar chemical structures, but quite different effects on our bodies. THC is the compound that is responsible for the euphoria associated with cannabis. CBD on the other hand does not alter the mind in this way, but instead may reduce pain and inflammation.

Could THC or cannabis cure cancer?

This is a difficult question to answer with certainty, because research into cannabis and the chemicals in cannabis is still in its infancy. There are also different strains of cannabis that have different levels of the various cannabinoids, which means that not all cannabis will have the same effect on your body.

Most of the research so far has only involved work in cells and mice but here are some of the findings so far:

Some cannabinoids have been found to inhibit the growth of tumour cells in test tubes and mice, but others encourage growth. Human studies are still small and hard to come by.
One study of cannabis users found that they had a lower risk of bladder cancer, but their risk of developing prostate cancer increased.
In the US dronabinol, a drug containing THC, is sometimes prescribed for patients to deal with the side effects of chemotherapy.
In 2021 a new clinical trial was launched in the UK to test whether a cannabis-based mouth spray could treat brain tumours and help patients live longer.

Are there any benefits to using cannabis if you have cancer?

There is no evidence that cannabis can treat or cure cancer. Although there has been some research around the use of cannabis as a cancer treatment, there is so far no sufficient evidence to suggest using it as a cure.

What is the latest research on cannabis and cancer?

There is a lot of interest in the potential to use cannabinoids to treat cancer. Researchers have found that some cannabinoids appear to help stop some types of cancer, but may actually encourage other cancers to grow. So more research is needed to better understand if and how cannabinoids could work as a cancer treatment.

You may have heard about some research around cancer and cannabis. Most of the studies have been small, lab-based experiments rather than large clinical trials involving cancer patients. Bigger research programmes would be needed to discover if cannabinoids can work to stop cancer in patients.

Are cannabis-based medicines available in the UK?

There are only a few cannabis-based medicines available in the UK and very few people are likely to get an NHS prescription for medical cannabis.

Epidyolex is a liquid containing CBD that can be prescribed for children or adults with epilepsy, and Nabiximols can be prescribed for spasms and muscle stiffness associated with multiple sclerosis.

For cancer patients speficially, chemotherapy often causes severe nausea and a medicine called Nabilone can be prescribed to help with this, designed to act in a similar way to cannabis.

All of these medicines can only be prescribed by a specialist doctor and only when other treatments have not worked.

Has Worldwide Cancer Research funded any research into cannabis and cancer?

No, Worldwide Cancer Research have not yet funded any research about cannabis and cancer. We are interested in bold, innovative, ideas that could lead to new ways to cure cancer though, so if we received an idea about cancer and cannabis that met our research strategy, then we would consider funding it. It is only by discovering more about cancer and about potential new cures, that we will reach a day where no life is cut short by cancer.