Cannabis Oil and Cancer – A Review of What We Know About the Science

Researchers from around the world have been exploring the relationship between cannabis oil and cancer over the last ten years, and researchers in the UK continue to research if there are cannabis-based medicines that may be able to assist patients during their traditional treatments for cancer.

Although there is currently no scientific or clinical evidence available that shows that cannabis oil cures cancer; however, studies have found that a few of the prescription cannabinoids have provided some symptom relief with a focus on nausea and vomiting related to chemotherapy.

So, what do we actually know about using cannabis for cancer, and where does the evidence fall short?

Cannabis Oil: What Is It?

“Cannabis oil” is a generic term.

Someone searching for CBD oil cancer research may be interested in cannabidiol, while another person looking into THC oil cancer treatment may be investigating tetrahydrocannabinol. These compounds work differently, and the products containing them are not necessarily interchangeable.

Types of Cannabis Oil Compared

CBD is generally considered non-intoxicating, while THC is the main psychoactive compound responsible for the “high”.

Both interact, directly or indirectly, with the body’s endocannabinoid system, a complex network involved in appetite, pain, mood and other physiological processes.

It’s also worth clearing up a common misunderstanding about hemp oil and cancer. Ordinary hemp seed oil contains little or no cannabinoids and should not be confused with CBD-rich or THC-rich cannabis extracts.

The National Cancer Institute’s review of cannabis and cannabinoids explains these differences in more detail.

Cannabis Oil for Cancer Treatment: What Are the Potential Benefits?

Cannabinoid medicines have been studied as alternatives to conventional treatments for many symptoms associated with chemotherapy and other types of cancer treatments.

However, the quality of available research has varied widely depending on both the symptom treated and the specific form of the drug used.

• Nausea and vomiting caused by chemotherapy – While prescription cannabinoid medicines (such as nabilone) may offer relief for some patients whose symptoms did not respond to their prescribed anti-sickness medicines, this is one area where more study has been done than others.

• Management of chronic pain – Results are conflicting and few studies provide consistent data that supports cannabinoids as an alternative to current pain medication options.

• Appetite loss – The appetite stimulant properties of THC appear to work well for some, but no evidence from clinical trials demonstrates a significant impact on either patient weight gain or improvement in nutritional status.

• Insomnia (difficulty sleeping) – Many patients indicate they sleep better when using cannabis products, however, very little high-quality research exists to support the use of cannabis to treat insomnia related to cancer.

• Anxiety and emotional distress – While research into the use of CBD to treat anxiety is ongoing, currently, we do not have enough reliable information to recommend CBD for anxiety secondary to cancer diagnosis. Additionally, THC can cause increased levels of anxiety in some individuals.

The National Cancer Institute’s clinical evidence review discusses these potential benefits and the limitations of existing studies.

Does Cannabis Oil Cure Cancer?

From the standpoint of clinical evidence, the answer is clear: cannabis oil has not been proven to cure cancer in humans.

You may have come across personal stories claiming that someone’s cancer disappeared after they started using cannabis oil. Others refer to laboratory experiments showing that cannabinoids can affect cancer cells.

But neither provides reliable proof of an effective cancer treatment.

As Cancer Research UK explains in its evidence review, further human clinical trials are needed to determine whether any of these experimental findings could lead to effective treatments.

What About Brain and Lung Cancer Research?

Glioblastoma is one form of a very aggressive type of tumour which has been studied as part of this effort.

Nabiximols, a pharmaceutical product that contains both THC and CBD was studied in a randomised, placebo controlled, Phase 1B clinical trial that included patients with recurrent glioblastoma who were receiving temozolomide chemotherapy.

The study consisted of 27 participants across two different portions of the study. Researchers found that the treatment combination was well tolerated; however they did note what appeared to be a potential for a survival signal that warrants further investigation. Due to the limited number of participants and additional limitations to the study it was not feasible for the researchers to determine whether there would be a statistically significant survival advantage.

You can view the full clinical study by clicking on “View Full Clinical Study” under the section entitled “Original Research Article.”

A follow-up Phase II clinical trial called ARISTOCRAT has since been developed to investigate the treatment combination further. The published clinical trial protocol describes the research hypotheses and study design; however, the fact that the protocol exists does not provide conclusive proof that the treatment will work.

Cannabis Oil Cancer Cure Claims: What Should You Look Out For?

Not every product advertised as medicinal has been properly tested, and not every claim about cancer is supported by scientific evidence.

Before trusting information about ganja oil cancer treatments, CBD extracts or other cannabinoid products, look carefully at what is being promised.

Warning Signs

• Promises of a guaranteed cure – Be sceptical of anyone claiming that cannabis oil can eliminate cancer.

• Advice to stop conventional treatment – Delaying chemotherapy, surgery or radiotherapy in favour of an unproven alternative may have serious consequences.

• Testimonials presented as scientific proof – Personal experiences cannot replace controlled clinical trials.

• Unclear cannabinoid content – Products without reliable THC and CBD information may pose additional risks.

• No independent laboratory testing – A lack of reliable testing makes it harder to know what a product actually contains.

A certificate of analysis (COA) can help identify cannabinoid content and certain contaminants. However, it does not establish that a product is safe for cancer patients or effective against cancer.

What Are the Risks of Using Cannabis Oil During Cancer Treatment?

Cannabis oil is not without risks, particularly for people undergoing cancer treatment.

THC-containing products may cause dizziness, drowsiness, anxiety, changes in heart rate and difficulties with concentration or memory.

CBD can also cause adverse effects and influence enzymes involved in processing certain medicines. This creates concerns about possible interactions, although the clinical significance depends on the particular drugs and doses involved.

The National Cancer Institute’s professional review discusses these interactions and the limitations of current evidence.

Questions to Ask Your Oncology Team

Before considering cannabis-based products, it may help to ask:

1. Could CBD or THC interact with my current cancer treatment?

2. Is there a licensed medicine with evidence for the symptom I’m trying to manage?

3. Could cannabinoids affect my liver function or other medication?

4. Are there safer or better-studied alternatives?

5. How would possible side effects be monitored?

This is particularly important for anyone receiving chemotherapy, taking anti-seizure medicines or using several prescription drugs.

Is Cannabis Oil Legal in the UK?

UK law distinguishes between consumer CBD products, controlled cannabis substances and prescription cannabis-based medicines.

The UK government’s CBD guidance explains the relevant requirements.

THC-containing cannabis oils are generally controlled under UK drug legislation, although certain cannabis-based medicinal products may be supplied through lawful specialist prescribing arrangements.

The NHS guide to medical cannabis explains the limited circumstances in which cannabis-based medicines may be prescribed.

It’s also important not to confuse availability with medical effectiveness. A product being sold online does not mean that it has been approved to treat cancer.

This applies equally to hemp oil cancer claims and products marketed as natural alternatives to conventional treatment.

Interested in How Cannabis Oil Is Made?

Understanding how cannabis oil is produced can help explain why different products vary in cannabinoid concentration, composition and consistency.

If you’re curious about the preparation process, take a look at our guide on how to make cannabis oil at home without fancy equipment.

Keep in mind that homemade oils are not standardised medicines, their strength can be unpredictable, and producing THC-containing preparations without the appropriate authorisation may be illegal in the UK.

Cannabis Oil and Cancer: The Future of Research

Scientists are continuing to investigate how cannabinoids interact with cancer cells, the immune system and the tumour microenvironment.

If you’re considering a cannabis-based product during cancer treatment, speak to your oncology team and rely on information from established medical organisations.

At Canna City, we also explore cannabinoids, different cannabis products and developments in cannabis research. Browse our educational articles to learn more about the subject and the science behind it.