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Cannabis (Marijuana) and Cannabinoids: What You Need To Know

Chemical structures for structures for cannabichromene, cannabinol, and cannabigerol overlay an image of the marijuana leaf.

Is marijuana the same thing as cannabis?

People often use the words “cannabis” and “marijuana” interchangeably, but they don’t mean exactly the same thing.

  • The word “cannabis” refers to all products derived from the plant Cannabis sativa.

  • The cannabis plant contains about 540 chemical substances.
  • The word “marijuana” refers to parts of or products from the plant Cannabis sativa that contain substantial amounts of tetrahydrocannabinol (THC). THC is the substance that’s primarily responsible for the effects of marijuana on a person’s mental state. Some cannabis plants contain very little THC. Under U.S. law, these plants are considered “industrial hemp” rather than marijuana.

Throughout the rest of this fact sheet, we use the term “cannabis” to refer to the plant Cannabis sativa.

What are cannabinoids?

Cannabinoids are a group of substances found in the cannabis plant.

What are the main cannabinoids?

The main cannabinoids are THC and cannabidiol (CBD).

How many cannabinoids are there?

Besides THC and CBD, more than 100 other cannabinoids have been identified.

Has the U.S. Food and Drug Administration (FDA) approved cannabis or cannabinoids for medical use?

The FDA has not approved the cannabis plant for any medical use. However, the FDA has approved several drugs that contain individual cannabinoids.

  • Epidiolex, which contains a purified form of CBD derived from cannabis, was approved for the treatment of seizures associated with Lennox-Gastaut syndrome or Dravet syndrome, two rare and severe forms of epilepsy.
  • Marinol and Syndros, which contain dronabinol (synthetic THC), and Cesamet, which contains nabilone (a synthetic substance similar to THC), are approved by the FDA. Dronabinol and nabilone are used to treat nausea and vomiting caused by cancer chemotherapy. Dronabinol is also used to treat loss of appetite and weight loss in people with HIV/AIDS.

Are cannabis or cannabinoids helpful in treating health conditions?

Drugs containing cannabinoids may be helpful in treating certain rare forms of epilepsy, nausea and vomiting associated with cancer chemotherapy, and loss of appetite and weight loss associated with HIV/AIDS. In addition, some evidence suggests modest benefits of cannabis or cannabinoids for chronic pain and multiple sclerosis symptoms. Cannabis isn’t helpful for glaucoma. Research on cannabis or cannabinoids for other conditions is in its early stages.

The following sections summarize the research on cannabis or cannabinoids for specific health conditions.

Are cannabis and cannabinoids safe?

Several concerns have been raised about the safety of cannabis and cannabinoids:

  • The use of cannabis has been linked to an increased risk of motor vehicle crashes.
  • Smoking cannabis during pregnancy has been linked to lower birth weight.
  • Some people who use cannabis develop cannabis use disorder, which has symptoms such as craving, withdrawal, lack of control, and negative effects on personal and professional responsibilities.
  • Adolescents using cannabis are four to seven times more likely than adults to develop cannabis use disorder.
  • Cannabis use is associated with an increased risk of injury among older adults.
  • The use of cannabis, especially frequent use, has been linked to a higher risk of developing schizophrenia or other psychoses (severe mental illnesses) in people who are predisposed to these illnesses.
  • Marijuana may cause orthostatic hypotension (head rush or dizziness on standing up), possibly raising danger from fainting and falls.
  • The FDA has warned the public not to use vaping products that contain THC. Products of this type have been implicated in many of the reported cases of serious lung injuries linked to vaping.
  • There have been many reports of unintentional consumption of cannabis or its products by children, leading to illnesses severe enough to require emergency room treatment or admission to a hospital. Among a group of people who became ill after accidental exposure to candies containing THC, the children generally had more severe symptoms than the adults and needed to stay in the hospital longer.
  • Some long-term users of high doses of cannabis have developed a condition involving recurrent severe vomiting.
  • There have been reports of contamination of cannabis/cannabinoid products with microorganisms, pesticides, or other substances.
  • Some cannabis/cannabinoid products contain amounts of cannabinoids that differ substantially from what’s stated on their labels.

Can CBD be harmful?

There’s evidence that CBD may be harmful to some people.

Before the FDA approved Epidiolex (a purified CBD product) as a drug, studies were done to evaluate its effectiveness and safety. Some participants in these studies had side effects (mostly diarrhea or sleepiness), and some developed abnormalities on tests of liver function. In some instances, study participants had to discontinue Epidiolex because of liver problems. Epidiolex also interacted with some of the other drugs these people were taking.

Problems like these can be managed in patients taking Epidiolex because they’re using CBD under medical supervision. People who use CBD on their own don’t have this kind of protection. They may not even know how much CBD they’re taking. A 2017 analysis of 84 CBD products sold online found that 26 percent contained substantially less CBD than the label indicated, and 43 percent contained substantially more.

Research Funded by the National Center for Complementary and Integrative Health (NCCIH)

Several NCCIH-funded studies are investigating the potential pain-relieving properties and mechanisms of action of substances in cannabis, including minor cannabinoids (those other than THC) and terpenes (substances in cannabis that give the plant its strain-specific properties such as aroma and taste). The goal of these studies is to strengthen the evidence regarding cannabis components and whether they have potential roles in pain management.

NCCIH is also supporting other studies on cannabis and cannabinoids, including:

  • An observational study of the effects of edible cannabis and its constituents on pain, inflammation, and thinking in people with chronic low-back pain.
  • Studies to develop techniques to synthesize cannabinoids in yeast (which would cost less than obtaining them from the cannabis plant).
  • Research to evaluate the relationship between cannabis smoking and type 2 diabetes.

More To Consider

  • Don’t use cannabis or cannabinoids to postpone seeing a health care provider about a medical problem.
  • Take charge of your health—talk with your health care providers about any complementary health approaches you use. Together, you can make shared, well-informed decisions.

For More Information

NCCIH Clearinghouse

The NCCIH Clearinghouse provides information on NCCIH and complementary and integrative health approaches, including publications and searches of Federal databases of scientific and medical literature. The Clearinghouse does not provide medical advice, treatment recommendations, or referrals to practitioners.

Toll-free in the U.S.: 1-888-644-6226

tty (for deaf and hard-of-hearing callers):

1-866-464-3615

Website: https://nccih.nih.gov/

Email: info@nccih.nih.gov (link sends e-mail)

PubMed®

A service of the National Library of Medicine, PubMed® contains publication information and (in most cases) brief summaries of articles from scientific and medical journals. For guidance from NCCIH on using PubMed, see How To Find Information About Complementary Health Approaches on PubMed.

Website: https://pubmed.ncbi.nlm.nih.gov/

MedlinePlus

To provide resources that help answer health questions, MedlinePlus (a service of the National Library of Medicine) brings together authoritative information from the National Institutes of Health as well as other Government agencies and health-related organizations.

Website: https://www.medlineplus.gov/

Key References

Acknowledgments

NCCIH thanks D. Craig Hopp, Ph.D., Inna Belfer, M.D., Ph.D., and David Shurtleff, Ph.D., NCCIH, for their review of the 2019 edition of this publication.

This publication is not copyrighted and is in the public domain. Duplication is encouraged.

NCCIH has provided this material for your information. It is not intended to substitute for the medical expertise and advice of your health care provider(s). We encourage you to discuss any decisions about treatment or care with your health care provider. The mention of any product, service, or therapy is not an endorsement by NCCIH.

Last Updated: November 2019