Cancer is the uncontrolled growth of abnormal cells in the body. Many cancers form solid tumors, though there are some exceptions (such as cancers of the blood). The common environmental and behavioral factors that may lead to cancer include: tobacco, diet and obesity, infections, radiation, lack of physical activity, and pollution in the environment. Heredity factors also increase the risk of some cancers.
Chemotherapy plays a major role in fighting the disease. But this treatment also affects normal, non-cancerous cells in your body. It causes a number of serious and unpleasant symptoms that include severe nausea, vomiting, fatigue, loss of appetite (anorexia) and depression.
Radiation Therapy is a localized treatment but can cause damage to the surrounding tissue near the cancer cells. This can result in pain as well as nutritional dysfunction, particularly when the gastrointestinal (GI) tract or central nervous system is irradiated. Often the side effects include nausea, headache, anorexia, dysphagia, malabsorption along with malnutrition. This can lead to dramatic weight loss, fatigue and insomnia. Many patients also suffer from anxiety and depression.
Cancer and Cannabis
NOTE FOR FIRST TIME READERS: Cannabinoids – such as THC, CBD – and terpenes are the main medically active components in cannabis (aka marijuana). For more information on these components, and much more about the plant, see our section on the Science of Cannabis.
There’s a wide range of benefits for cancer patients who use cannabis. In fact, it may even be more effective than other medications currently being used to treat the condition. It’s commonly acknowledged that medical marijuana helps to relieve nausea, vomiting and loss of appetite that can come from chemotherapy or radiation therapy. It has long been prescribed in the form of Marinol, the only federally approved form of THC. In addition, cannabis is used to treat the chronic pain or depression that may accompany cancer treatments. There is increasing amounts of evidence that suggest its use outweighs using prescription medication. And recent scientific research has found that cannabinoids can affect tumor growth as well.
Older studies on using cannabis for treating nausea and vomiting in cancer patients found it to be equally effective, if not better than the conventional medications available at the time. Currently, there are new, non-cannabis based medications that are very effective for these symptoms but some patients don’t respond to them or cannot tolerate (or afford) these pharmaceuticals. For these patients, medical cannabis is a viable alternative.
There are years of research showing that cannabis works well as a painkiller without the serious side effects of conventional painkillers. For those with advanced cancer suffering from severe pain, cannabis works synergistically in combination with opioid painkillers. This allows patients to reduce the amount of medication they take, which in turn lowers the risk of taking higher doses of opioids. Using cannabis in this way decreases pain while limiting the problems like nausea or loss of appetite as well as the risks of accidentally overdosing.
It‘s generally agreed that cannabis doesn’t cause cancer and, in some cases, may inhibit the growth of tumors. This is well documented in studies of the gliomas (brain or spinal tumors), where cannabinoids have been shown to decrease their growth in animals. In 2006, researchers did the first ever pilot study in humans looking at using THC to shrink recurrent brain tumors. It showed there was some decrease in tumor growth among a portion of the patients. In March of 2011, investigators at the British Columbia Children’s Hospital in Vancouver reported the regression (or shrinking) of brain tumors in two teenagers who were regularly inhaling cannabis and were not receiving any other conventional treatment.
There is active research looking into cannabidiol (CBD) as a potential treatment for aggressive breast cancer. Researchers found that CBD inhibits a gene that is believed to be responsible for the metastatic process that spreads cells from the original cancer tumor throughout the body. Additionally, separate research studies have shown that cannabinoids inhibit the growth and spread of various cancer cell lines including breast carcinoma, prostate carcinoma, colorectal carcinoma, gastric adenocarcinoma, skin carcinoma, leukemia cells, neuroblastoma, lung carcinoma and others.
The National Cancer Institute recently reported research on cannabinoids and cannabis: “The potential benefits of medicinal cannabis for people living with cancer include antiemetic effects, appetite stimulation, pain relief, and improved sleep. In the practice of integrative oncology, the health care provider may recommend medicinal cannabis not only for symptom management but also for its possible direct anti-tumor effect.” Their website also states: “Cannabinoids have a favorable drug safety profile. Unlike opioid receptors, cannabinoid receptors are not located in the brainstem areas controlling respiration; therefore, lethal overdoses due to respiratory suppression do not occur. Although cannabinoids are considered by some to be addictive drugs, their addictive potential is considerably lower than that of other prescribed agents or substances of abuse.”
The dosage regimen to actually treat cancer with cannabis is individualized and should be supervised by a professional. For symptom relief, both CBD and THC treat nausea in low doses (5-10 mg). (See also the section on Anorexia for appetite stimulation).
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