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Cancer Health Center

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Cannabis and Cannabinoids (PDQ®): Complementary and alternative medicine - Patient Information [NCI] - Overview

  • Cannabis, also known as marijuana, is a plant grown in many parts of the world which produces a resin containing compounds called cannabinoids. Some cannabinoids are psychoactive (acting on the brain and changing mood or consciousness) (see Question 1).
  • The use of Cannabis for medicinal purposes dates back to ancient times (see Question 3).
  • By federal law, the use, sale, and possession of Cannabis is illegal in the United States. However, a growing number of states and the District of Columbia have enacted laws to legalize medical marijuana (see Question 1).
  • In the United States, Cannabis is a controlled substance requiring special licensing for its use (see Question 1 and Question 3).
  • Cannabinoids are active chemicals in Cannabis that cause drug -like effects throughout the body, including the central nervous system and the immune system (see Question 2).
  • Cannabinoids can be taken by mouth, inhaled, or sprayed under the tongue (see Question 5).
  • Cannabis and cannabinoids have been studied in the laboratory and the clinic for relief of pain, nausea and vomiting, anxiety, and loss of appetite (see Question 6 and Question 7).
  • Cannabis and cannabinoids may have benefits in treating the symptoms of cancer or the side effects of cancer therapies (see Question 7).
  • Two cannabinoids (dronabinol and nabilone) are drugs approved by the U.S. Food and Drug Administration (FDA) for the prevention or treatment of chemotherapy -related nausea and vomiting (see Question 7 and Question 10).
  • Cannabis has been shown to kill cancer cells in the laboratory and to affect the immune system. However, there is no evidence that Cannabis' effects on the immune system help the body fight cancer (see Question 6).
  • At this time, there is not enough evidence to recommend that patients inhale or ingest Cannabis as a treatment for cancer-related symptoms or side effects of cancer therapy (see Question 7).
  • Cannabis is not approved by the FDA for use as a cancer treatment (see Question 9).

    This information is produced and provided by the National Cancer Institute (NCI). The information in this topic may have changed since it was written. For the most current information, contact the National Cancer Institute via the Internet web site at http:// cancer .gov or call 1-800-4-CANCER.

    WebMD Public Information from the National Cancer Institute

    Last Updated: May 28, 2015
    This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.
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