Addiction Drug Use Marijuana Cannabidiol and Its Effects 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. Learn about our editorial process Elizabeth Hartney, BSc., MSc., MA, PhD Medically reviewed by Medically reviewed by Steven Gans, MD on August 05, 2016 Steven Gans, MD is board-certified in psychiatry and is an active supervisor, teacher, and mentor at Massachusetts General Hospital. Learn about our Review Board Steven Gans, MD Updated on May 26, 2019 Print Khmanglo/Flickr Cannabidiol, or CBD, is an active ingredient in the drug cannabis, also known as marijuana. CBD is the second-most widely recognized element of marijuana, after delta-9-tetrahydrocannibinol, or THC. Marijuana contains over 400 different active substances, with THC and CBD being just two of its 60 different cannabinoid molecules. Effects 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 several hundred times 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 potentiallly 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 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 neuroprotective effect on the same areas of the brain. Another study looking at the effects of various drugs on the development of dementia showed that CBD may have some positive effects, including the reduction of symptoms of psychosis in people with Parkinson's Disease. However, it is too early to say whether CBD could be used to prevent dementia, a condition which the medical system is struggling to cope with as it is reaching epidemic proportions among the aging population. There is also some research to suggest that CBD may reduce symptoms of psychosis in people with Parkinson's disease. Amount of Cannabidiol in Cannabis 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 has been around 4% of each substance. In contrast, "high potency" strains of marijuana that have been developed more recently, such as sinsemilla, or "skunk," are reported to contain 16-22% of THC, and less than 0.1% CBD. This might explain the recent increase in cannabis-related cases of psychosis. Was this page helpful? Thanks for your feedback! Learn the best ways to manage stress and negativity in your life. Sign Up You're in! Thank you, {{form.email}}, for signing up. There was an error. Please try again. What are your concerns? Other Inaccurate Hard to Understand Submit Article 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. Demirakca, T., Sartorius, A., Ende, G., Meyer, N., Welzel, H., Skopp, G., Mann, K. & Hermann, D. "Diminished Gray Matter in the Hippocampus of Cannabis Users: Possible Protective Effects of Cannabidiol." Drug & Alcohol Dependence, 114:242-5. 2011. Englund, A., Morrison, P., Nottage, J., Hague, D., Kane, F., Bonaccorso, S., Stone, J., Reichenberg, A., Brenneisen, R., Holt, D., Feilding, A., Walker, L., Murray, R., and Kapur, S. "Cannabidiol Inhibits THC-elicited Paranoid Symptoms and Hippocampal-dependent Memory Impairment." Journal of Psychopharmacology [online] 1-9. 2012. Scuderi, C., Filippis, D., Iuvone, T., Blasio, A., Steardo, A. & Esposito, G. 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