What Is Cannabidiol (CBD)?

Man looking at a bottle of cannabidiol.

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What Is Cannabidiol (CBD)?

Cannabidiol, or CBD, is an active ingredient in the drug cannabis, also known as marijuana. CBD is the second-most prevalent compound of marijuana, after delta-9-tetrahydrocannabinol, or THC. Marijuana contains over 400 different active substances, and THC and CBD are just two of its 60 different cannabinoid molecules.

Cannabidiol can be derived from either the hemp plant or the cannabis plant. It contains THC when derived from marijuana plants, while hemp-derived cannabidiol contains only trace amounts of the psychoactive compound.

Types of Cannabidiol

Cannabidiol is available in a number of different forms and can be found in a wide variety of products. The three main types of cannabidiol that are available are:

  • Full-spectrum: This means the product contains other compounds that are found in the cannabis plant, including varying amounts of THC.
  • Broad-spectrum: This type contains other compounds found in cannabis, but does not contain THC.
  • Isolate: This type contains only cannabidiol and not other cannabis compounds.

Products that may contain cannabidiol include oils, sprays, capsules, lotions, candies, and beverages. It can be administered in oral, topical, edible, or inhaled forms.

Some research suggests that taking full-spectrum cannabidiol products may be beneficial thanks to something known as the entourage effect. Essentially, taking CBD and THC together maximizes the therapeutic benefits.


Cannabidiol may have a number of uses. Some evidence suggests that it might have therapeutic applications in the treatment of conditions including:

It is important to note that while cannabidiol shows promise in the treatment of some symptoms and conditions, further research is needed. Additional studies may explore variations in dosages and administration as well as how treatment with cannabidiol compares to other medications and treatment options.

Impact of Cannabidiol

There is increasing evidence that CBD may have potential therapeutic benefits, including anticonvulsive, sedative, hypnotic, antipsychotic, and neuroprotective properties. It also has an anti-inflammatory effect, which in animal studies has been found to be more potent than that of aspirin (acetylsalicylic acid).

Because CBD produces its biological effects without acting significantly on the brain's cannabinoid receptors, it does not cause the unwanted psychotropic effects that are characteristic of other marijuana derivatives.

This gives it a potentially high potential to be used in the development of various forms of medical marijuana. A study comparing THC with CBD showed that some of the unpleasant aspects of the marijuana high, such as anxiety and paranoia, appear to be caused by THC, and alleviated by CBD.

Although the subject is complex, studies have shown some neuroprotective effects of CBD. Research comparing the brains of chronic marijuana smokers and the amount of THC and CBD on hair samples indicated that, while THC appears to have a neurotoxic effect—diminishing grey matter in areas of the brain—CBD appears to have a protective effect on the same areas of the brain.

Another study looking at the effects of various drugs on dementia showed that CBD may have positive effects on some of the behavioral manifestations of the disease. There is also some research to suggest that CBD may reduce symptoms of psychosis in people with Parkinson's disease.

Tips When Taking Cannabidiol

Before you decide to try cannabidiol, it is important to consider what you are trying to achieve. If your goal is to relieve symptoms of a condition such as depression or anxiety, ingested or inhaled products are more likely to have therapeutic effects than topical applications. Inhaled cannabidiol begins working quite quickly, while edible or other ingested products may take longer.

If you are interested in a localized application, such as to relieve skin problems or muscle inflammation, a topical product such as a cream, ointment, lotion, or salve might be preferable.

It is also important to consider the quality of the product itself. One 2017 study published in the Journal of the American Medical Association found that less than a third (31%) of cannabidiol products sold on the internet were labeled correctly. Many contained less CBD than advertised or also had significant amounts of THC.

Potential Pitfalls

While research suggests that cannabidiol is generally well tolerated, you may experience some side effects while taking CBD products. Some of these side effects can include:

  • Appetite changes
  • Anxiety
  • Diarrhea
  • Drowsiness
  • Dry mouth
  • Mood changes
  • Nausea
  • Vomiting

If you are considering taking CBD, always be sure to talk to your doctor or healthcare provider. Some CBD products may interact with other medications or supplements, so be sure to share any other substances you might be taking with your doctor.

Despite the current view that CBD appears to be both a positive agent in and of itself and a potential modifier of some of the negative aspects of THC, reports of how the constituents of cannabis have changed over the first decade of the 21st century are concerning.

Typical reports of the amount of THC and CDB in cannabis have been around 4% of each substance. In contrast, "high potency" strains of marijuana that have been developed more recently have been reported to contain 16% to 22% THC and less than 0.1% CBD. This might explain the increase in cannabis-related cases of psychosis.

15 Sources
Verywell Mind uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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By Elizabeth Hartney, BSc, MSc, MA, PhD
Elizabeth Hartney, BSc, MSc, MA, PhD is a psychologist, professor, and Director of the Centre for Health Leadership and Research at Royal Roads University, Canada.