We’ve said it before on this website, cannabis plants are very complex and contain many hundreds of substances. Now that scientific research on cannabis is prospering after years of virtual downtime, we are finally beginning to better understand this complex plant. The research on cannabinoids such as CBD, for instance, taught us a lot about the many potential therapeutic applications of this substance. At the same time there are many constituents that we know lesser about, terpenes for example. Nevertheless, terpenes are interesting ingredients and it is assumed that they play an important role in the medicinal effects of cannabis products. In this article we will discuss what we know about terpenes and what their possible functions are.
Terpenes are substances that can be found in numerous plants. We can notice the presence of terpenes by the scent that is spread by plants. For example, the terpene limonene gives citrus fruits their smell (and taste). Menthol is also a fragrance that has its origin in the presence of certain terpenes. People who smoke cannabis know that there are differences in how various cannabis strains taste and smell. Terpenes, which are volatile, have a big influence on this taste and smell.
Besides the impact on smell and taste, there are also scientific implications that terpenes have a therapeutic effect. Not only do terpenes have their own individual effect, they all so work synergistically with other components. In particular, terpenes affect the effects of various cannabinoids and in particular those of CBD. This effect, in which one component enhances (or inhibits) the action of the other component, is also called the entourage effect.
For this article, we used two scientific publications that provide an overview of the knowledge that has been gathered on terpenes in cannabis plants so far [1,2]. We have selected four of the main terpenes and describe their possible applications in below. Both publications can be found online and are definitely worth reading if you want to know more about therapeutic use of terpenes. The links to these studies can be found in the citation underneath this article.
Of all known terpenes limonene is the second most common. Limonene can be found, for example, in lemons and oranges. Studies with laboratory animals indicate that limonene has a powerful anxiolytic effect. The scent of limonene could have an antidepressant effect as well, as shown by one study. Finally, there are indications that limonene can help against symptoms of acne.
This terpene has an anti-inflammatory effect that is further enhanced when it is used together with CBD. In higher doses myrcene also has a calming effect. In conjunction with the cannabinoid THC this can lead to what is also known as couch-lock (the inability to get off the couch). Some people experience this effects as pleasant, but for many medicinal users of cannabis products this is an unwanted side-effect.
In all of nature pinene is the most common terpene. It occurs in the essential oils of many plants, for instance in conifers. Pinene helps to keep insects away from plants. Research shows that pinene (like myrcene) has an anti-inflammatory effect. In addition to that pinene can dilate the airways and act as an antibiotic. Pinene also has a beneficial effect on memory. We know that the cannabinoid THC negatively affects the short-term memory, pinene appears to reduce this adverse effect.
This terpene is a major constituent of lavender. We know lavender gives some relief form skin burns, and also reduces the formation of scar tissue. It is likely that this effect is caused by linalool. In addition to this, anxiolytic and sedative effects of linalool have also been observed.
The ideal composition
There are many types of plants and every plant has a unique profile of constituents. In particular, the terpenes profile can vary greatly between species. In addition to this, there are numerous factors of influence on the final terpenes profile, such as the conditions under which a plant grows (for example the number of sun hours). Even plants of the same species can have different terpenes profiles. When you use a therapeutic cannabis product (such as CBD oil) it is important to gain knowledge of the terpenes profile of this product. That way you’ll know if your product is suited for the purpose that you have in mind. For instance, we can imagine that you’d choose a product that contains relatively little myrcene and a relatively big amount of pinene (to avoid the adverse effects of THC as much as possible). To find out the terpene profile of your product you can have it tested in a laboratory.
Finally, there is still a lot to discover about terpenes. Since THC was isolated for the first time in 1964 by Raphael Mechoulam, this cannabinoid got almost all of the attention for years. Only much later was the focus slightly shifted to other cannabinoids such as CBD. The latest development is that now terpenes are starting to get some well-deserved attention. This article is certainly not the last that we will publish on terpenes. Check our website regularly if you want to stay up to date on the latest news.
- Russo, E.B. (2011) Taming THC: potential cannabis synergy and phytocannabinoid-terpenoid entourage effects. Br J Pharmacol., 163(7): 1344-64.
- Andre, C.M., Hausman, J., & Guerriero, G. (2016) Cannabis sativa: The Plant of the Thousand and One Molecules, Front Plant Sci. Online gepubliceerd, februari 2016.