Cannabis Use During Cancer Treatment: What Patients Should Know

As medical cannabis becomes increasingly accessible and popular among cancer patients, it's important to understand the potential benefits, risks, and limitations of its use during cancer treatment. Recent studies have shed light on this growing trend and what it might mean for both patients and healthcare providers.

Between 20% to 40% of cancer patients use cannabis or cannabinoids to manage treatment-related side effects such as nausea, pain, sleeplessness, anxiety, and stress. This trend has grown alongside the increasing number of states legalizing cannabis for medical use.

Cannabis is now legal for medical use in 14 states and for both recreational and medical use in 24 states plus the District of Columbia. However, it remains illegal at the federal level as a Schedule 1 drug. Patients should be aware of their state's specific laws regarding cannabis use.

Some doctors report that their younger patients are more likely to use cannabis, often for issues related to anxiety or trouble sleeping. Older patients may be more reluctant to try cannabis, but are willing to consider it. What’s important for patients to remember, however, is that cannabis is not a treatment for cancer.

Potential Benefits and Risks

While many patients believe the potential benefits of cannabis outweigh the risks, it's important to note that scientific evidence supporting its clinical use in cancer treatment is limited. In fact, most studies show limited or no benefit to its use in most cases. Some potential risks include:

1. Interference with cancer treatments: Small studies suggest cannabis may make immunotherapy less effective.

2. Immune system suppression: Long-term use can potentially suppress the immune system.

3. Drug interactions: Cannabis can interact with other medications, potentially increasing sedative effects.

4. The cost of cannabis use may increase financial strain for a person undergoing cancer treatment without quality evidence of its clinical benefit.

Gary Ellison, Ph.D., M.P.H, of NCI’s Division of Cancer Control and Population Sciences said there’s still not enough information for doctors to have a good handle on safety of cannabis use for those in cancer treatment. More clinical trials on the effects of cannabis during cancer treatment are needed before any safety and effectiveness can be determined.

Communication with Healthcare Providers

Healthcare providers often feel they don’t have enough information to discuss cannabis use with patients because there are so few studies available. The American Society of Clinical Oncology (ASCO) published its first clinical guidelines on cannabis use in March 2024, acknowledging that patient use has outpaced scientific evidence.

Open communication with oncologists about cannabis use is important. Only about 20% of patients using cannabis report discussing it with their oncologist. However, patients should inform their healthcare providers about all supplements they're taking, including cannabis products. This information can help providers better manage side effects and adjust treatment plans if necessary.

For those who decide to use cannabis during their cancer treatment, here are a few tips:

1. Discuss cannabis use with your oncologist, even if they don't bring it up first.

2. Be aware that cannabis can affect multiple body systems, including the brain, lungs, and heart.

3. Understand that while cannabis may help manage symptoms, it is not a proven cancer treatment.

4. Consider potential interactions with other medications you're taking.

5. Stay informed about the legal status of cannabis in your state and your healthcare facility’s policies.

Adapted from "As More People with Cancer Use Medical Cannabis, Oncologists Face Questions They Struggle to Answer" from the National Cancer Institute.

Citations:

[1] https://www.cancer.gov/news-events/cancer-currents-blog/2024/medical-cannabis-oncologists-patients-communication

[2] https://www.cancer.gov/news-events/cancer-currents-blog/2024/medical-cannabis-oncologists-patients-communication