Cancer Research

By James Tindall, PhD

Marijuana and Cancer
Marijuana is the name given to the dried buds and leaves of varieties of the Cannabis plant, that generally will grow wild in tropical climates and that is cultivated commercially. It is also called pot, grass, cannabis, weed, hemp, hash, marihuana, ganja, and dozens of others.

Prior to the pharmaceutical industry coming on the scene, marijuana has been used in herbal remedies for centuries. Scientists have identified many biologically active components in marijuana called cannabinoids. The two best studied components are the chemicals delta-9-tetrahydrocannabinol (often referred to as THC), and cannabidiol (CBD). Other cannabinoids also are being studied.

The U.S. Drug Enforcement Administration (FDA) lists marijuana and its cannabinoids as a Schedule I controlled substance, which means they cannot legally be prescribed, possessed, or sold under federal law excepting states like Colorado and others who have legalized marijuana.

Whole or crude marijuana (including marijuana oil or hemp oil) also is not approved by the FDA for any medical use. But the use of marijuana to treat some medical conditions is legal under state laws in many states.

Dronabinol and Nabilone, are a pharmaceutical form of THC, and a man-made cannabinoids are approved by the FDA to treat some conditions, but have been found to be less effective than the natural plant because of the complex terpenes and flavanoids compounds that are not present in synthetic drugs forms.

Marijuana
It is really not known how many compounds are in marijuana plants, but there are many, which makes it difficult to do systems type research in the USA, many are researched separately. Different compounds in marijuana have different actions in the human body. For example, delta-9-tetrahydrocannabinol (THC) causes the “high” reported by consumers of the substance, and also can help relieve pain and nausea, reduce inflammation, and acts as an antioxidant. It can also lead to feelings of anxiety and paranoia in some people. Cannabidiol (CBD) can help treat seizures, reduce anxiety and paranoia, and counteract the “high” caused by THC.

Different cultivars (sativa and indica) and even different crops of marijuana plants can have varying amounts of these and other active compounds. This means that marijuana can have different effects based on the strain used.
The effects of marijuana also vary depending on how marijuana compounds enter the body.

When taken by mouth, THC can take hours to be absorbed. Once it’s absorbed, it’s processed by the liver, which produces a second psychoactive compound (a substance that acts on the brain and changes mood or consciousness) that affects the brain differently and may affect each user differently depending on the type of cannabis.

When marijuana is smoked or vaporized (inhaled), THC enters the bloodstream and goes to the brain quickly. The second psychoactive compound is produced in small amounts, and has less effect. Generally, the effects of inhaled marijuana fade faster than marijuana taken by mouth.

Marijuana affects symptoms of cancer?
A number of small studies of smoked marijuana discovered that it can be helpful in treating nausea and vomiting from cancer chemotherapy. A few studies found that inhaled (smoked or vaporized) marijuana can be helpful treatment of neuropathic pain (pain caused by damaged nerves). Smoked marijuana has also helped improve food intake in HIV patients in studies. Currently, there are very few studies in people of the effects of marijuana oil or hemp oil, but the latter has found to be more beneficial than Omega type oils.

Studies have long shown that people who took marijuana extracts in clinical trials tended to need less pain medicine. 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 laboratory dishes. Some animal studies also suggest certain cannabinoids may slow growth and reduce spread of some forms of cancer.

There have been some early clinical trials of cannabinoids in treating cancer in humans and more studies are planned. While the studies so far have shown that cannabinoids can be safe in treating cancer. However, most studies are not done in the U.S. due to FDA restrictions, which hopefully will change since much research that has been done has shown CBD’s compounds extremely beneficial, dose dependent, on a wide variety of illness from seizures to cancer.

Cannabinoid drugs
There are 2 chemically pure drugs based on marijuana compounds that have been approved in the U.S. for medical use.

• Dronabinol (Marinol®) is a gelatin capsule containing delta-9-tetrahydrocannabinol (THC) that’s approved by the US Food and Drug Administration (FDA) to treat nausea and vomiting caused by cancer chemotherapy as well as weight loss and poor appetite in patients with AIDS.
• Nabilone (Cesamet®) is a synthetic cannabinoid that acts much like THC. It can be taken by mouth to treat nausea and vomiting caused by cancer chemotherapy when other drugs have not worked.

Nabiximols is a cannabinoid drug still under study in the U.S. It’s a mouth spray made up of a whole-plant extract with THC and cannabidiol (CBD) in an almost one to one mix. It’s available in Canada and parts of Europe to treat pain linked to cancer, as well as muscle spasms and pain from multiple sclerosis (MS). It’s not approved in the U.S. as of 2015, but it’s being tested in clinical trials to see if it can help a number of conditions.

How can cannabinoid drugs affect symptoms of cancer?
Based on a number of studies, dronabinol can be helpful for reducing nausea and vomiting linked to chemotherapy. Dronabinol has also been found to help improve food intake and prevent weight loss in patients with HIV. In studies of cancer patients, though, it wasn’t better than placebo or another drug (megestrol acetate).
Nabiximols has shown promise for helping people with cancer pain that’s unrelieved by strong pain medicines, but it hasn’t been found to be helpful in every study done. Research is still being done on this drug.

Side effects of cannabinoid drugs
Like many other drugs, the prescription cannabinoids, dronabinol and nabilone, can cause side effects and complications. Some people have trouble with increased heart rate, decreased blood pressure (especially when standing up), dizziness or lightheadedness, and fainting. These drugs can cause drowsiness as well as mood changes or a feeling of being “high” that some people find uncomfortable. They can also worsen depression, mania, or other mental illness. Some patients taking nabilone in studies reported hallucinations. The drugs may increase some effects of sedatives, sleeping pills, or alcohol, such as sleepiness and poor coordination. Patients have also reported problems with dry mouth and trouble with recent memory.

Older patients may have more problems with side effects and are usually started on lower doses. People who have had emotional illnesses, paranoia, or hallucinations may find their symptoms are worse when taking cannabinoid drugs.

Talk to your doctor about what you should expect when taking one of these drugs. It’s a good idea to have someone with you when you first start taking one of these drugs and after any dose changes.

What does the American Cancer Society say about the use of marijuana in people with cancer?
The American Cancer Society supports the need for more scientific research on cannabinoids for cancer patients, and recognizes the need for better and more effective therapies that can overcome the often debilitating side effects of cancer and its treatment. The Society also believes that the classification of marijuana as a Schedule I controlled substance by the U.S. Drug Enforcement Administration imposes numerous conditions on researchers and deters scientific study of cannabinoids. Federal officials should examine options consistent with federal law for enabling more scientific study on marijuana.

Medical decisions about pain and symptom management should be made between the patient and his or her doctor, balancing evidence of benefit and harm to the patient, the patient’s preferences and values, and any laws and regulations that may apply. Despite the pros and cons of marijuana, still, to this date, not one single death has ever been caused directly from marijuana.

To learn more
Stay tuned for more articles about marijuana and its benefits in which we will focus on health benefits, not smoking pot as it were and getting high. Cancer and other illnesses are serious and bring significant changes to individuals and families. Thus, we will limit articles to those that show the pros and cons of ailment treatment with CBD’s and related marijuana plant constituents. Thanks for reading.

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