RSO (Rick Simson Oil) is an oil made from the flowers of the cannabis plant that gets attention online from people who claim it treats cancer. There’s no solid evidence for it. But some early research suggests that some chemicals in marijuana have future potential as a cancer treatment.[1]

I have no idea if this the case or not, so if you’re from the FDA, rest assured that I’m not espousing RSO as a cancer treatment. But I get asked the question enough that I feel some history is in order.

Who is Rick Simson?

Rick Simpson begins this story as an engineer in a Canadian hospital in the 90s. At the time, his world and the world of cannabis did not intersect. But after an accident in which Simpson fell from a ladder and sustained head trauma, he began to suffer from chronic dizzy spells and a ringing in his ears. Though his doctors tried to help, medicine had little effect on these symptoms. Simpson’s hope was renewed when he saw a documentary about medical cannabis. He acquired some cannabis of his own and saw significant relief with its use.

Years later, Rick Simpson was diagnosed with basal cell carcinoma. Remembering his previous success with cannabis and having read a study in which THC was effective against cancer in mice, he decided to try treating his condition by applying concentrated cannabis oil topically. After four days of constant exposure to cannabis oil, Simpson’s cancerous growths had disappeared. The experience made a believer out of Simpson, and he distributed his cannabis oil and spread the word about what had happened to him.[2]

Though more research needs to be done on the effects of RSO on cancer symptoms, a 2022 clinical review demonstrated the vast use of medicinal cannabis for cancer and treatment-related symptoms. However, the study also indicated that healthcare professionals did not have significant insight into how to integrate cannabis-related care into regular treatment.

From The American Cancer Society website: “More recently, scientists reported that THC and other cannabinoids such as CBD slow growth and/or cause death in certain types of cancer cells growing in lab dishes. Some animal studies also suggest certain cannabinoids may slow growth and reduce spread of some forms of cancer.”[3]

A couple of years ago after learning about the alleged connection between cannabis and cancer tumors, I started giving CBD oil to my dog who had a history of getting benign, fatty tumors on her back which we would periodically have lanced and drained by our vet. Since starting on CBD, she has not had a single tumor.

I’m in no way suggesting relying on marijuana alone as treatment while avoiding or delaying conventional medical care for cancer as that may have serious health consequences.

Cannabis has not been legal for a sufficient time to have conclusive clinical results yet, but initial research and the preponderance of empirical evidence like mine provides a compelling argument for its consideration.

[1] https://www.webmd.com/cancer/rick-simpson-oil-for-cancer-overview

[2] https://www.veriheal.com/blog/who-is-rick-simpson-and-what-is-the-significance-of-rso/

[3] https://www.cancer.org/cancer/managing-cancer/treatment-types/complementary-and-integrative-medicine/marijuana-and-cancer.html