Several studies show the effect of prolonged use of cannabis on the levels of eCBs. For example, Morgan et al.  observed a reduction of AEA levels in the cerebral spinal fluid (CSF), while an increase in 2-AG levels in the serum of chronic cannabis users. Furthermore, Leweke et al.  have shown that a two-week treatment with CBD increased circulating levels of AEA, PEA, and OEA in the serum of schizophrenia patients. In a recently published paper by our group , we also showed that different high-CBD cannabis extracts modulate the levels of eCB and eCB-like lipids in mouse brains and serum.
Cannabis or its derivatives are widely used by patients with cancer to help with cancer symptoms and treatment side effects. However, cannabis has potent immunomodulatory properties. To determine if cannabis consumption during immunotherapy affects therapy outcomes, we conducted a prospective observatory study including 102 (68 immunotherapy and 34 immunotherapy plus cannabis) consecutive patients with advanced cancers who initiated immunotherapy. Cannabis consumption correlated with a significant decrease in time to tumor progression and overall survival. On the other hand, the use of cannabis reduced therapy-related immune-related adverse events. We also tested the possibility that cannabis may affect the immune system or the tumor microenvironment through the alteration of the endocannabinoid system. We analyzed a panel of serum endocannabinoids (eCBs) and eCB-like lipids, measuring their levels before and after immunotherapy in both groups. Levels of serum eCBs and eCB-like lipids, before immunotherapy, showed no significant differences between cannabis users to nonusers. Nevertheless, the levels of four eCB and eCB-like compounds were associated with patients’ overall survival time. Collectively, cannabis consumption has considerable immunomodulatory effects, and its use among cancer patients needs to be carefully considered due to its potential effects on the immune system, especially during treatment with immunotherapy.
Minor differences between groups of users vs. nonusers were found in liver or renal functions or the electrolytes balance before the initiation of the anticancer immunotherapy ( Table 2 ). Differences were also found in terms of the lymphocyte count at baseline (before immunotherapy), where 67% of cannabis users (IC-G group) showed low lymphocyte counts (without leukopenia) vs. 51% in non-cannabis users (I-G group) (one-tailed p = 0.08) ( Table 2 ). In other words, the users group had 16% more cases of low lymphocytes at baseline, which corresponds to a low-to-medium difference between groups (Cohen’s h = 0.31).
To date, no large-scale studies have shown CBD to have benefits for the treatment of people with cancer. Most studies that have been done evaluating CBD as a cancer treatment were in mice or in human cells in the lab. For instance, there are some studies that have shown that CBD inhibits the growth of cancer cells in mice with lung cancer or colon cancer. Another study showed that CBD, together with THC, killed glioblastoma cancer cells in the lab. However, no studies have been conducted in people with cancer.
It is also important to note that some studies have shown that CBD might interfere with how your body processes cancer drugs, called a drug interaction. This might make cancer treatments more toxic or make them less effective. More research is needed on these effects, too. For these reasons, always tell your oncologist if you’re thinking about using CBD before you take it.
There is currently 1 CBD treatment approved by the U.S. Food and Drug Administration (FDA) called Epidiolex, which is used to treat a rare and severe form of epilepsy in children. There are not currently any FDA-approved CBD medications for treating cancer or side effects of cancer treatments.
Can CBD help people with cancer?
You may also be wondering if CBD is legal in your area. Some states allow the sale and possession of cannabis, including CBD and THC, for medical and recreational use. Others have stricter regulations, so state-by-state laws should always be learned before transporting CBD across state lines. Things are more complicated at the federal level. In 2018, the U.S. government recognized that hemp can be grown and manufactured legally as part of the Farm Act. Hemp can be used to make things like rope and clothing, in addition to CBD oil. In other words, hemp is no longer a controlled substance, which means it is not regulated by the government. This means that consumers have to evaluate the safety and quality of CBD products on their own. Some CBD, for example, may have much higher levels of THC than what is labeled.
Cannabidiol, also known as CBD, is one of many chemicals found in the cannabis plant. It has been touted in some online forums as an alternative treatment, and even a cure, for many illnesses, including cancer. And, some people with cancer say that CBD has helped them as a complementary therapy in managing their symptoms and side effects from standard cancer treatment.
What is CBD?
CBD is 1 of the hundreds of chemicals found in the flowering cannabis plant. CBD does not have the psychoactive, or mind-altering, effects of another chemical found in cannabis called tetrahydrocannabinol (THC). THC is the chemical that causes people to experience a “high.” CBD, on the other hand, is being used by some to help ease pain, anxiety, and sleep issues.
You may find stories online of people discussing the benefits of CBD as a cancer treatment or as relief for side effects. Please remember that such personal stories, while they may be well-meaning, are shared without scientific study and do not constitute evidence. The safety and efficacy of CBD for people with cancer still has to be proven in large, randomized, controlled clinical trials.