

Cannabinoid Fact Check
Use our interactive tool to look up scientifically supported answers to key questions on cannabinoids and cannabis-based products.
- There are many different types of cannabinoids – some are natural, either found in plants or made endogenously in the human body, and some are synthetic1
- Phytocannabinoids are naturally occurring cannabinoids produced by the Cannabis sativa L species of plants.1 There are over 120 different known phytocannabinoids2
- Only a few are thought to be present in reasonable quantities2
- The two best characterised are cannabidiol (CBD) and delta-9-tetrahydrocannabinol (THC)3
- There are also endocannabinoids: molecules made by the body that bind and interact with the cannabinoid receptors as well as other neurotransmitter systems. The primary endocannabinoids identified to date are anandamide (also known as N-arachidonoylethanolamine [AEA]) and 2-arachidonoylglycerol (2‑AG)4,5
- Finally, synthetic cannabinoids are designed to replicate or closely resemble natural cannabinoids and/or to interact with cannabinoid receptors (known as CB1 and CB2)6,7
- There are a number of cannabinoids that have been studied in animals, including, but not limited to, cannabichromene (CBC), cannabidivarin (CBDV), cannabigerol (CBG) and delta-9-tetrahydrocannabivarin (THCV).1,2 Some have even been investigated in humans in early phase studies.3,4 However, these cannabinoids have not yet reached advanced clinical trials in patients
- Better understanding of the pharmacology of cannabinoids and their testing through clinical trials will continue to improve our knowledge of their potential medicinal properties
Additional information
- CBC, one of the most abundant cannabinoids in cannabis plants, is the end-product of cannabidiolic acid (CBDA) when it is broken down by heat or UV light.5,6 Some studies in animals have explored its anti-inflammatory and analgesic effects,1,5 though this has not been tested in humans
- CBG has been reported to have anti-inflammatory and anxiolytic-like effects in mouse models,1,2 but this has not been studied in human patients
- CBDV and THCV (the propyl analogues of CBD and THC, respectively) may have different effects to CBD and THC because of differences in their structure.1,6 Both have been explored in early phase human trials,3,4 but not yet in advanced randomised clinical trials, and more scientific evidence is required to better understand their medicinal potential
- The legal status of cannabinoids differs depending on the type of cannabinoid, the type of product that contains them, and also by country1–3
- There are many known phytocannabinoids,4 and controlled drugs regulations apply to some (e.g. delta-9-tetrahydrocannabinol [THC] and cannabinol [CBN]) but not others (e.g. cannabidiol [CBD]).1,5 This means products that only contain CBD (i.e. CBD-based consumer products) are assessed differently to those containing THC1,5
- There are also country-level differences in the regulations and legal status of different cannabis-based products that are important to be aware of:1–3,5
- Regulatory approved cannabis-based medicines are subject to strict medicines regulations and are legally available via prescription in those countries for which a licensed indication exists2,5,6
- For ‘Medical cannabis’ (non-regulatory approved cannabis-based products), the legal situation varies by country1,3,7
- For CBD-containing products and foods (such as oils and supplements), the legal status varies and in some cases is unclear in certain countries3,7–10
- The use of cannabis for recreational purposes is illegal in most EU countries3
- Our understanding of cannabinoids is continuing to grow, but there is a need for additional, high-quality evidence for their use as disease- and symptom-modifying treatments1
- Although there are many different cannabinoids, and several of these have been evaluated in a variety of formulations and routes of administration, only a few therapeutic uses have been thoroughly tested in clinical studies in patients2,3
- Finally, while there is public interest in cannabis as a “cure” for conditions, including cancer,4 it is important to differentiate between the management of a condition and its symptoms, and treatment that is truly curative. Cannabis-based products have not yet been proven to “cure” any condition5,6
- For those cannabinoids that have gained regulatory approval as treatments of disease symptoms, their approved use varies between countries2,5,7
- Of the 120+ known cannabinoids, only a small number of them are associated with the euphoric 'high' linked with cannabis use1,2
- The euphoria is brought about through activation of the CB1 receptor;1 examples of cannabinoids with euphoric effects include delta-9-tetrahydrocannabinol (THC) and cannabinol (CBN).2 The extent of the euphoric effects depends on the dose and route of cannabinoid administration3,4
- Other cannabinoids, including cannabidiol (CBD), cannabichromene (CBC) and cannabidivarin (CBDV) do not activate the CB1 receptor and so are not associated with intoxicating or euphoric effects;5 although these may be associated with other effects, e.g. somnolence in the case of CBD6,7
- Cannabis is a generic term for the Cannabis sativa L plant and its products1,2
- Marijuana is a term used for cannabis that is used recreationally, most typically through smoking2
- ‘Medical cannabis’ is a broad term used to describe some cannabis-based products. These are used for medical purposes but are not approved by medicines regulators2,3
- Cannabidiol (CBD) oils consist of CBD extracted from the cannabis plant (often from industrial hemp) diluted in a carrier oil or solvent, and are one of the most available forms of CBD sold over the counter.4,5 These products are not medicines, their labels should not make medical claims, and they should not be advertised as medicines4–7
- Quality of CBD oils can vary, and products may not contain the amount of CBD that their label indicates, because of a lack of standardisation and quality control.8-10 They may also contain contaminants or other cannabinoids, including delta-9-tetrahydrocannabinol (THC), potentially even at levels sufficient to cause THC-associated adverse events11,12
- Please refer to the infographic What products contain cannabinoids? for more information
- Cannabidiol (CBD) and delta-9-tetrahydrocannabinol (THC) are two of the best characterised phytocannabinoids.1 Although they derive from the same plant and have the same chemical formula (C21H30O2), they differ in their structure and their effects2–5
- As with other cannabinoids, such as cannabichromene (CBC), cannabigerol (CBG), and tetrahydrocannabivarin (THCV), THC and CBD derive from the Cannabis sativa L plant4
- They have different structures and pharmacology.4 THC is thought to act primarily through CB1 receptors, which are predominantly found in the central nervous system, and it is through CB1 receptor activity that THC is believed to cause the acute, euphoric effects typically associated with recreational cannabis use4,5
- In contrast, the key mechanisms underlying the actions of CBD are currently unclear.5 CBD is not intoxicating, and is believed to act primarily at sites other than the cannabinoid receptors4,5
- While CBD and THC have different pharmacological actions and medical potential, ongoing scientific and clinical research is key to improving our understanding of their effects1
Additional information
- CBD and THC are made in the plant as acidic forms (cannabidiolic acid [CBDA] and tetrahydrocannabinolic acid [THCA]) and are decarboxylated to their neutral active forms1
- Over 120 different plant-based cannabinoids (phytocannabinoids) are produced by the Cannabis sativa L plant species.1,2 They are made as a sticky resin by structures called trichomes, which are most abundant in the flowers and upper leaves of the female cannabis plant1,3
- In contrast, synthetic cannabinoids are man-made. They are designed to replicate or closely resemble natural cannabinoids and/or to interact with cannabinoid receptors (known as CB1 and CB2)4,5
- Some synthetic cannabinoids have been approved as medicines5
- Synthetic cannabinoids can also be made illegally for recreational use e.g. spice and K2.4,6 These tend to be structurally unrelated to phytocannabinoids and often have a higher affinity for cannabinoid receptors than naturally occurring cannabinoids.6 Consequently, there is a risk of detrimental effects4,6
- It is important to be aware of the potential adverse events associated with any product containing cannabinoids, so that they can be weighed up against their potential benefits. There are many different types of products that are derived from cannabis or that include cannabinoids, and the associated risks will differ for each one*,†,1–4
- Please refer to the infographic What are the risks associated with cannabinoids? for more information
†In the UK, in addition to reporting adverse events to the manufacturer, they should be reported through the Yellow Card scheme conducted by the MHRA. Further information can be found at https://yellowcard.mhra.gov.uk/ or via the MHRA Yellow Card app.
1. Whiting et al. JAMA 2015;313:2456–73; 2. Pratt et al. Syst Rev 2019;8:320; 3. Ladha et al. Molecules 2020;25:4042; 4. Bonomo et al. Br J Clin Pharmacol 2018;84:2495–8.