Since Ethan Russo, cannabis researcher, proposed the concept of the “entourage effect”, terpenes have come under scientific scrutiny as potential contributors to the therapeutic effects of cannabis and hemp. Myrcene is one such terpene.
Terpenes are not exclusive to cannabis; in fact, any aromatic plant is rich in terpenes. Eucalypts are rich with eucalyptol while lemons are abundant in limonene. Terpenes are responsible for the aromatic properties of a plant, and often carry with them an entire plethora of therapeutic properties. They form the entire basis in which aromatherapy is grounded.
Myrcene is one of the most abundant terpenes found in cannabis. It is also found in mangos, lemongrass, basil, and hops. There is speculation that myrcene makes the blood-brain barrier more permeable to intoxicants (such as cannabinoids) — another potential example of the entourage effect.
Remember what terpenes are?
They are the aromatic compounds of a plant. Over 20,000 terpenes are known to exist, and virtually every plant produces its own kind of terpenes. They are responsible for giving a plant its unique aroma and flavor, and they are the major constituents of herbal essential oils.
It is most likely that terpene production is an adaptive quality of plants specifically for the purpose of repelling predators and attracting pollinators. As is the case with cannabis, the climate, altitude, and season all play a role in a plant’s ability to produce terpenes.
Different varieties of hemp and cannabis contain different terpenes, and in different concentrations. This is what contributes to the variance in aroma and taste. They also play a role in the variation in effect. Though CBD and THC are present in all varieties of cannabis, different strains tend to have different effects. Some are uplifting while others are heavily sedating. Arguably the biggest factor in this variation is the presence of different terpenes.
So, what is Myrcene?
As with virtually all other terpenes, Myrcene, otherwise known as β-myrcene, is an organic hydrocarbon. Its chemical formula is C10H16. Other than cannabis, Myrcene is highly prevalent in wild thyme (which can contain up to 4% Myrcene by weight), hops, verbena, cardamom, mango and lemongrass.
While Myrcene’s consumption is mainly limited to food products such as mangoes, it is also often used as an intermediate in perfumery. It has a balsam, peppery aroma, and although it is never used on its own, it is used in the preparation of flavor and aroma products. The flavor of Myrcene also contributes to the flavor of beer, and not surprisingly so, as it is abundant in hops.
Interestingly, Myrcene is considered to be the active sedative component of hops, thus justifying the possibility that it plays the same role in cannabis. Myrcia sphaerocarpa is a Brazilian shrub rich with myrcene, and it was traditionally used to treat dysentery, hypertension, diarrhoea, and diabetes.
Myrcene and the entourage effect
The mango is seen by cannabis users as a proverbial “gateway” to cannabis because of the allegation that Myrcene increases permeability of the blood-brain barrier. Myrcene might do this by increasing the permeability of cell membranes, with a special affinity for the cells that protect the brain. There is, as yet, no scientific data that supports this speculation, although it has been shown to increase transdermal absorption. Its effects on skin cells may be an indication to Myrcene’s behaviour on other cells in the body.
The proposition that Myrcene increases cell membrane permeability is one example of the entourage effect. The potential for terpenes to synergize the effects of cannabinoids is perfectly exemplified by the speculation that Myrcene increases cell membrane permeability. Much of the time, these synergistic effects are not notable when a compound is taken on its own, but only when in conjunction with other compounds — like cannabinoids!
As briefly mentioned earlier, scientists have demonstrated the sedating effects of myrcene. In one rodent study, mice given high doses of myrcene showed levels of sedation comparable to phenobarbital. On top of this, myrcene is also a proven analgesic.
What many often forget is that the therapeutic potential of CBD or THC is compounded and regulated by the hundreds of other compounds present in a specimen of hemp or cannabis. All in all, cannabinoids make up a tiny fraction of what’s present in cannabis, though they are present in the highest abundance.
The reason that terpenes are important to the cannabis conversation is that they are these mediating compounds responsible for potentiating, regulating, and down-regulating the effects of cannabinoids. As one of the most abundant terpenes, Myrcene likely plays a role in cannabis and hemp’s analgesic properties. This is especially so for cannabinoids that are applied topically, as Myrcene is proven to increase transdermal absorption.
Though cannabinoid isolates (such as CBD isolate) have their own, unique applications, the entourage effect illustrates the importance of “whole plant medicine”. For therapeutics manufactured from plant material, it is imperative to consider the plant as a whole, intelligent being. In this case, terpenes are just as important as cannabinoids.