Cannabis oil and ovarian cancer: the facts

19 July 2018
Cannabis oil

Using cannabis oil as a means to treat or cure cancer is a topic of much online debate and the internet is full of people claiming that it has effectively helped to cure their cancer. We take a closer look at the evidence behind these claims.  

The cannabis plant produces a resin that contains various substances, including cannabinoids, which may have medicinal value. Cannabis has been shown to kill cancer cells in the laboratory and there are currently many research projects worldwide exploring whether its properties could be harnessed to help stem the growth of malignant tumours. Several of these studies are summarised in this Nature Reviews Cancer report.

However, while many of these studies show exciting early promise, killing cancer cells in a laboratory is far simpler than killing cancer cells in the human body. Until a cancer treatment has gone through the full stages of testing in animals and people, we cannot be certain that it works. Decades of cancer research has demonstrated that cancer is an incredibly complex and varied disease that varies from person to person and tumour to tumour. As a result, any claim that there could be a single cure for all cancers should be treated with a healthy dose of scepticism.

Scientific research requires robust evidence; vital for determining whether or not a potential cancer treatment is actually safe and effective. Publishing this data then allows health organisations and medical professionals to judge the information for themselves and use it for the benefit and safety of their patients.

At this time, therefore, there is not enough evidence to recommend that patients use cannabis oil as a treatment for ovarian cancer.

If you’re considering using cannabis oil, it’s also important to know the risks:

  • Although some forms of low-concentrate cannabis oil are available to buy for medical purposes in British pharmacies, cannabis itself is classified as a class B drug in the UK, meaning that it’s illegal to possess or supply it. This includes cannabis oil with a percentage of THC higher than 0.05%
  • When buying cannabis oil online, there is no way of verifying its strength or the ratio of CBD and THC, (the active chemicals found in the plant that cause the ‘high’ sought by recreational users)

  • Cannabis makes some people feel confused, anxious or paranoid. It can also affect memory, make you feel faint and sick or sleepy and lethargic.

  • Some studies have demonstrated that cannabinoids can have the opposite effect, encouraging cancer cells to grow.

As a research-based organisation, it is of paramount importance that there is reliable scientific evidence to support claims made about any cancer treatment, as lives are at stake. While it’s tempting to think that a cancer patient has nothing to lose by trying an alternative treatment, in fact, there are big risks. Taking medications outside of those recommended by your oncologist may have interactions and additional side-effects, so consult a medical professional before taking anything new.


For more information, please visit the cannabis & cancer FAQs on the Cancer Research UK website