Mounting Evidence That Medicinal Cannabis Kills Cancer

Looking back through history, there’s no doubt that cannabis has had a bad press. Some have worried that the THC component of cannabis could raise the risk of psychosis and other mental health problems, and the CBD component has been dragged down at the same time. But now cancer sufferers and clinicians are lining up to sing its praises, with compelling clinical-observational and evidence that CBD represents a life-changing – and in some cases, life-saving – treatment for some.

In 2018, the US-based International Institute of Anticancer Research conducted a clinical trial that assessed the objective responses of a range of cancer patients to pharmaceutical-grade CBD. The results of the study, which looked at 119 cancer patients over a four-year period, were revealing: clinical responses to CBD were observed in 92% of the patients with solid tumours, including a reduction in circulating tumour cells in many cases, and a reduction in tumour size in others. Based on these results, the authors of the study concluded that CBD could represent a potential treatment for breast cancer and glioma patients.

Powerful Testimonies And Clinical Observations From Cancer Sufferers And Clinics

Perhaps the most emotive testament to the healing properties of CBD comes straight from the mouths of clinicians and sufferers themselves. Many cancer patients claim that CBD has had a significant impact on the symptoms of their illness – including nausea from aggressive chemotherapy treatment and post-treatment pain. But others go further, reporting that CBD is actually helping to kill their cancer in the first place.

In 2016, Joy Smith, from Coventry, started to use CBD tablets after being diagnosed with terminal bowel and stomach cancer, having read about a US patient who had gone into remission after going down the same route. Nearly two years later, doctors described Ms Smith as ‘the luckiest woman in the world’ as her scans revealed just a small amount of the disease was left in her stomach.

Then in 2018, Susan Dhillon from Slough was diagnosed with inoperable stage four cancer of the mouth, nose and lower skull. After five months of taking a cannabis tablet a day, doctors were stunned to discover that some of her tumours had disappeared, and others had stopped growing or shrunk altogether. Susan’s consultant said: “’When I reviewed Mrs Dhillon on January 17 I was pleasantly surprised to see regression of the cancer in the oral cavity with no evidence of any obvious tumour in the palate. There is no evidence of any active cancer in the nasal cavity. A CT scan in December 2018 has also confirmed stable disease with no evidence of any progression.”

An oral mucosal formulation called Nabiximols (Sativex®) is available in the United Kingdom for spasticity in MS. It is also approved by Health Canada as an adjunct treatment for neuropathic pain in MS, and for moderate to severe cancer‐related pain for patients who have failed the highest tolerated opiate dosing. In April 2014, the FDA granted Fast Track designation to Sativex® for the treatment of pain in patients with advanced cancer, who experience inadequate analgesia during optimized chronic opioid therapy, and it is currently undergoing phase III clinical trials in the US for this indication.

Medicinal cannabis may have a role in headache disorders other than migraine as well. A case study reported a woman with pseudotumor cerebri would smoke a marijuana cigarette about once per week when her headache was more severe. She would have complete resolution of her headache within 5 minutes, and it would not recur that day.198 This is interesting given other studies that suggest that cannabinoids may reduce intracranial pressure in traumatic brain injury,199-203 as well as intraocular pressure in glaucoma.204-216 The synthetic cannabinoid, Dexabinol, has no psychotropic activity, but blocks NMDA receptors, and suppresses production of tumor necrosis factor. In phase II trials in Israeli hospitals, it lowered intracranial pressure with a trend toward faster and better neurologic outcome.199, 203

How Does CBD Help To Fight Cancer?

So how does CBD work to fight cancer? Early scientific studies have indicated that different cannabinoids may have the power to tackle cancer in three key ways: one, by causing a cell to die; two, by stopping cells from dividing; and three, by stopping cells from developing new blood vessels.

When it comes to the power of CBD, scientific research continues apace. But amazing stories from cancer suffers continue to hit the headlines, raising hopes that medicinal cannabis will soon be readily available to the people who need it most. As Cancer Research UK says: “[…] we are supportive of properly conducted scientific research into cannabis and its derivatives that could benefit cancer patients and we will continue to monitor developments in the fields and evidence as it emerges”.


1. Dr. George J. Delinasio, International Institute of Anticancer Research, 2018.

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