There are lots of chemicals, otherwise known as cannabinoids, found in the cannabis plant. Tetrahydrocannabinol (THC), cannabidiol (CBD), cannabichromene (CBC), tetrahydrocannabivarin (THCV), cannabigerol (CBG) and cannabinol (CBN) are known as the “big six” cannabinoids. You’ve probably heard of most of them, especially if you’ve read some of our earlier cannabis science blogs. They are cannabinoids found in higher amounts in the cannabis plant compared to other cannabinoids, as well as being cannabinoids of particular medical interest.
Now, to get a little bit confusing, CBC, THCV, CBG and CBN are considered minor cannabinoids. Only THC and CBD are considered the major cannabinoids. However, as we’ve already looked at the big 6, we’ll take a look at some of the other cannabinoids that could have some therapeutic properties. This blog explores 10 rarer cannabinoids and how they could be used by medical cannabis patients.
1. Tetrahydrocannabiphorol (THCP)
Recently discovered by researchers Guiseppe Cannazza and several others, THCP is a cannabinoid that is thought to have a 33-fold greater affinity to CB1 receptors than THC. This means that THCP is more psychoactive than THC. THCP tends to show up in extremely low concentrations when it does show up, but some varieties of cannabis may produce more THCP and be particularly potent.
2. Tetrahydrocannabutol (THCB)
Discovered at the same time as THCP, and also showing greater affinity for CB1 receptors than THC – this time about 15 times greater. Also found in small concentrations, suggesting that it rarely imparts any significant psychoactive effect. However, as with THCP, some varieties of cannabis may contain larger amounts of THCB. These cannabinoids may be of interest for those who are suffering from moderate to severe chronic pain.
Although THCB and THCP have the same chemical formula as THC, they have longer alkyl side-chains (7 compared to THC’s 5), making them more potent.
3. Cannabidivarin (CBDV)
Cannabidivarin is a homolog of CBD, i.e. they are very similar to each other, with the only difference being that the side-chain is shortened by two methylene bridges. CBDV is non-psychoactive, and could be useful as an antispasmodic and anticonvulsant for the treatment of epilepsy.
4. Cannabielsoin (CBE)
CBE is a metabolite of CBD. This means that, when CBD is processed by the body, one of the cannabinoids it turns into is CBE. There are no pharmacological uses described for CBE so far.
5. Cannabicyclol (CBL)
CBL is a degradative product of CBC, usually formed after exposure to sunlight. Very little is known about CBL, and this is the case of most cannabinoids outside of the big six due to the fact that they are found in such low amounts in the plant. CBL has been shown to have very little biological activity.
6. Cannabichromevarin (CBCV)
CBCV was discovered in 1975 in Thailand by the group of researchers from the University of Nagasaki. The chemical structure of CBCV is similar to CBC, but has a much shorter propyl group. Although little is known about CBCV, and CBCV is not active at cannabinoid receptors as far as we know, it could combine with other cannabinoids for its anti-tumor effects.
7. Cannabivarin (CBV)
CBV is similar to CBN, except the side-chain is shortened by two methylene bridges (-CH2-). Another difference is that CBV is an oxidized product of THCV. CBV is not considered to be psychoactive, We have very little knowledge about CBV and its potential medical applications. Its precursor, THCV, definitely does have many potential therapeutic uses, though.
8. Cannabicitran (CRM, CBT or CBM)
CRM comes from CBC. As with many of the other minor cannabinoids, very little is known about the pharmacological effects of CRM.
9. Cannabitriol (CBT C5)
Many people get confused between cannabitriol and cannabicitran, as they share the same three-letter acronym. However, they are quite different. CBT C5 has a similar structure to THC, but it is not known if it has similar psychoactive properties.
10. Cannabigerol Monomethyl Ether (CBGM)
CBGM is a cannabinoid classified into the CBG group. CBGM is similar to CBG in that it may be useful for conditions like Crohn’s disease, cancer and arthritis. However, even slight changes in chemical structure can make a difference in effects, and it can be difficult to determine any differences when CBG and CBGM come together, and CBGM is in much lower concentrations.
The Minor Cannabinoids: Overall
Even though many of the minor cannabinoids are often grouped together with the big 6 cannabinoids, small changes in a cannabinoid’s structure can cause vastly different physiological effects. They are also usually present in much smaller amounts compared to other cannabinoids, and often come as a package with them too, making it even more difficult to separate them out and get an idea of their effects on the human body.
However, there is much interest in these smaller cannabinoid groups for their unique effects (when they have them in the first instance). Expect to see a greater number of varieties in the future with greater concentrations of these minor cannabinoids.