There's a lot of talk about cannabis in the cancer world. Mainstream media, alternative health websites, and cancer survivors themselves have been touting the benefits of cannabis for many years.
But many cancer patients still struggle with the stigma of being a cannabis user and are often told by their doctors that it will interfere with their treatment. So what's the deal? Can cannabis really help people who have cancer?
What is Cannabis?
Cannabis (also known as marijuana or medical marijuana) is a plant that contains cannabinoids, which are chemical compounds that act on the brain and body. Certain cannabinoids are considered "psychoactive", which refers to any substance that enters the brain and stimulates neurons, altering brain function. This can lead to changes in perception, mood, consciousness, and behavior.
The two main cannabinoids found in cannabis are:
- THC: Responsible for the euphoric "high" sensations
- CBD: Non-psychoactive and doesn’t produce a “high”
Because cannabis contains these psychoactive compounds, it's considered regulated as a substance that has the potential for abuse.
There are also numerous other types of cannabinoids found in cannabis, including cannabinol (CBN), cannabicyclol (CBL), cannabichromene (CBC)—along with others. These have been shown to have properties that may help with a variety of conditions like pain, anxiety, depression, or nausea.
How Does Cannabis Work?
“Cannabis works by interacting with our endocannabinoid system (ECS) - which are receptors located in our central nervous system and throughout our entire body,” says Rebecca Abraham, Certified Cannabis Nurse and Founder of Acute on Chronic LLC. “It affects many different processes, hormones, and neurotransmitters in our body.” The ECS's primary function is to help maintain your body's internal equilibrium, often referred to as homeostasis.
The ECS is made up of three major components: endocannabinoids, receptors, and enzymes.
- Endocannabinoids: Molecules that carry signals between cells
- Receptors: The part of a cell where certain molecules can bind and cause a specific response
- CB1 receptors: Mostly found in the nervous system (central nervous system and peripheral nervous system)
- CB2 receptors: Mostly found in the immune system, tonsils, and associated structures
- Enzymes: Break down the compounds that bind to the receptors after the body has finished using them
When you use cannabis, cannabinoids enter your body and bind to CB1 and CB2 receptors. Your body recognizes this as a signal to do something, triggering a process that leads to the psychoactive and physiological effects you experience when using cannabis.
Does Cannabis Work for Cancer?
While there is no definitive evidence, there is some preliminary research that shows the active compounds in cannabis may have anti-tumor effects, among other benefits.
“One study shows that patients using cannabis and radiation together had a positive outcome,” explains Abraham. “In another study, cannabis seemed to enhance the anti-tumor effects of a chemotherapy drug on cells in the lab.”
“Findings like this are interesting (and hopeful!) and will hopefully lead to more research, but it would be way, way too soon to say that an individual person using cannabis would kill their cancer cells.”
In general, most cancer patients using Cannabis alongside their therapy are using it for symptom management. This usually includes things like nausea, anxiety, or pain.
Clinical research to date shows that cannabis may help with:
- Protect against certain types of tumors
- Increase appetite
- Reduce Nausea
- Decrease inflammation
- Alleviate pain
- Promote sleep
- Lower anxiety levels
What are the Side Effects of Using Cannabis to Treat Cancer?
As with any substance that acts on the brain, there is a risk for side effects. A major side effect of cannabis is impairment of motor function. It can cause problems with coordination and keep you from being able to perform daily tasks. Smoking cannabis can also cause respiratory problems, including bronchitis.
“The most concerning side effects are potential drug interactions. CBD and THC can interact with over 90 drugs, increasing the levels of some drugs and decreasing others,” adds Abraham.
“This means that by mixing cannabis and pharmaceuticals you may experience increased side effects or decreased therapeutic effects from pharmaceuticals. This can happen with some chemotherapy and immunotherapy treatments, which is why it is important to talk to your oncologist, provider, or cannabis clinician prior to using cannabis.”
The side effects of cannabis tend to be mild compared with the side effects of other treatments for cancer. Other notable potential side effects include:
- Changes in blood pressure or heart rate
- Anxiety
- Heightened physical sensations
- Dizziness
- Fatigue
- Confusion or disorientation
- Depression
- Difficulty with memory and concentration
How to Talk to Your Doctor About Using Cannabis for Cancer
No matter what alternative treatments you're using, it's important to talk with your healthcare provider so they can provide proper care and monitor your progress.
“Just say it! If your doctor is unwilling to talk about cannabis, find a provider that will. It’s important to discuss cannabis use (even CBD) with your provider, due to the number of drug interactions,” explains Abraham.
Your doctor should know you're using cannabis as a complementary treatment for cancer, so remember to be honest about how much cannabis you're using and any other drugs you're taking. Continue to watch for any signs that cannabis use is causing problems.
These tips that will help you have a meaningful conversation with your healthcare team:
- Educate yourself on cannabis, including its risks and benefits
- Be open with your doctor about your interest in using cannabis as an alternative therapy option
- Seek the guidance of a medical cannabis program or a certified cannabis nurse specialist
- Don't be afraid to advocate for yourself
How Can I Get Cannabis for Cancer Treatment?
You should always get your cannabis from a safe, legal source. If you live in a state where it has been legalized, talk to your doctor about getting a referral to a knowledgeable medical dispensary.
According to Abraham, if you:
- Live in a medical state: You need to obtain a medical card. In most states that means establishing continuity with a provider who will determine that you met the state's criteria for a card, and then submit paperwork to the state
- Live in a state where recreational cannabis is legal: You don't HAVE to get a card - but it will cost you considerably more, and several states have products that are reserved only for medical patients
- Live in a prohibition state: Hemp-based CBD (which has less than 0.3% THC in it) is available in all 50 states since the passage of the 2018 Farm Bill
If you're using cannabis for the first time, do so under the guidance of your doctor and start at a very low dose. The amount of cannabis that’s safe for one person isn't always safe for another, so be sure to follow expert advice when trying any new cannabis preparations.
Know that some people feel the effects of cannabis immediately, while others don't feel anything at all. Don't take more if you don't feel the effects.
Be sure to store your cannabis in a childproof container and keep it out of the reach of children and pets. The amount you're taking can be harmful if unintentionally ingested by another person.
Just like with other treatments, make sure you know how to use medical cannabis safely and effectively before starting treatment.
Is There a Risk of Addiction or Overdose With Cannabis?
The risk of addiction to cannabis is low. However, like any drug, it needs to be taken responsibly and as intended by a professional. Onestudy found that approximately 9% of cannabis users developed a dependency, much less than the 67.5% of those using nicotine and 22.7% of alcohol users.
“There has never been a reported death from cannabis. There is no lethal dose,” adds Abraham. “There is a slight risk of cannabis overuse syndrome which can affect less than 9% of cannabis users.”
Cannabis is also a much safer alternative to opioids and other medications often prescribed for pain. That said, it's still possible to over-consume medical cannabis.
What Resources are Available for Cancer Patients Using Cannabis?
There are several educational resources that will help you learn more about cannabis, including the science and potential benefits and risks.
- National Cancer Institute:Cannabis and Cannabinoids Patient Education
- Memorial Sloan Kettering Cancer Center:Cannabis for Patients and Caregivers
- Project CBD
- Society of Cannabis Clinicians
- American Cannabis Nurses Association
- Cannabis books written by medical professionals
Make an Informed Decision
Deciding to use cannabis for cancer may seem daunting, but there's a lot of support available. Talk to your doctor about whether cannabis could benefit you and consult with a certified medical cannabis professional.
