What Is CBD Oil, and Can It Help People with Cancer?

Cannabidiol (CBD) oil

Cannabidiol (CBD) oil has become more readily available since 2018, when Congress passed farm legislation that took hemp off the list of Schedule I controlled substances. CBD oil is derived from hemp.

Cannabidiol (CBD) oil is regularly touted for its healing properties. But is this popular elixir just another snake oil? Pharmacist Jason Hou, an integrative medicine specialist who manages Memorial Sloan Kettering’s About Herbs database, and Nirupa Raghunathan, an integrative medicine doctor at MSK with expertise in CBD, share what people with cancer should know before trying it.

It has not been clinically proven that CBD oil can help with symptoms of anxiety, poor sleep, and pain.

What is CBD oil?

Dr. Hou: CBD is one of many chemicals extracted from the cannabis plant, Cannabis sativa, also known as hemp. Most CBD oil on the market comes from cold-pressing whole hemp seeds. It’s different from delta-9-tetrahydrocannabinol, also known as THC, which is another chemical extracted from the cannabis plant.

Back to top

How can people with cancer use CBD oil?

Dr. Raghunathan: It is possible that CBD could have a benefit with symptoms of anxiety, poor sleep, and pain. CBD has been studied a lot in the laboratory and in mice but far less in humans. Right now there are some studies that are evaluating CBD as a part of cancer treatment, but none of those have had significant results. The studies that do show a benefit with CBD are for specific epilepsy syndromes in children.

Back to top

What do we know about how CBD oil works?

Dr. Hou: When CBD oil is taken by mouth, some amount is absorbed and becomes available in the blood. There are cannabinoid receptors throughout the human body, and when CBD binds to them, that can trigger biological effects. But the downstream effects are still unclear because currently, there are very few human data. Other edible products containing CBD are likely absorbed and metabolized in a similar manner as CBD oil. There is, however, limited absorption through the skin with topical CBD oil.

Dr. Raghunathan: How CBD works is not fully understood, but it seems to work through a variety of pathways in the body that have different effects. For example, it seems to have an anti-inflammatory effect, which is helpful with pain. It also works on serotonin receptors, which helps with anxiety. Because CBD works in many ways, people should discuss it with a doctor. It is important to understand both the possible benefits and risks.

Dr. Hou: We need more research to assess the safety and effects of CBD oil. And we need to take a closer look at potential herb-drug interactions, which is especially important for people receiving chemotherapy.

Back to top

Does CBD oil have psychoactive properties, like marijuana? Is it a sedative?

Dr. Raghunathan: CBD is not psychoactive in the same way that marijuana is. It doesn’t act on the cannabinoid receptors in the central nervous system, which is how THC works. However, it is possibly psychoactive because it works on serotonin receptors, and anything that affects mood is psychoactive. CBD has been studied in mice and seems to affect sleep-wake cycles. But CBD oil can be unexpectedly psychoactive and sedative because it’s not well-regulated. Studies have shown that some products that claim to be pure CBD actually have THC and other dangerous contaminants, such as opioids.

Dr. Hou: Since everyone responds to oral CBD differently, the side effects may range from mild sedation to cannabinoid hyperemesis syndrome. This is characterized by repeated and severe bouts of vomiting.

About Herbs, Botanicals & Other Products
Find evidence-based information from our Integrative Medicine experts about herbs, vitamins, and other dietary supplements.
Back to top

What do we know about CBD oil’s ability to fight or prevent cancer?

Dr. Hou: Currently, there is no clinical evidence for using CBD oil for cancer treatment or prevention. Some studies in cancer cell lines and in animal models found that CBD caused cancer cells to stop spreading and eventually die off. But those studies used highly concentrated and purified forms of CBD, which are not yet available to the general public. Clinical trials are needed to determine any potential anticancer effects of CBD.

Back to top

Where can people get CBD oil?

Dr. Raghunathan: If you make an appointment with MSK’s Integrative Medicine Service doctors, we can discuss CBD oil and whether it is appropriate for you. We don’t recommend it for all patients because everyone is different. If we recommend CBD for you, we will discuss how to find a higher quality, more reliable product so you actually get what you’re paying for.

Back to top


Commenting is disabled for this blog post.

I have bladder cancer and I’m on a support group Facebook page. Some people keep mentioning Rick Simpson oil and day they have been cured. Would this be a high quality CBD? I figured it was a bunch of nonsense. Thank you.

Dear Kate, the “Rick Simpson” posts are common on cancer-related blogs and message boards, and are an attempt to sell a product. Thank you for your comment and best wishes to you.