Terpenes: Their Role in Cannabis
Why Terpenes? Terpenes are found in a variety of plants and even in some insects. They are known for pungent aromas and a sharp taste. Their actions can be antimicrobial, insecticidal, antifungal, and antimold. They are abundant in cannabis, and the sharp taste protects the plant from pests and animals. The terpenes near the bottom of the plant are different than those at the top, thereby protecting it from different predators, including microbes. Terpenes are found in the trichomes of the cannabis plant and give the plant its aroma and much of the taste we associate with good cannabis. Scientific studies indicate that terpenes are probably responsible for some of the effects of cannabis as well. This is where the terpene conversation becomes interesting. If this is true, it may be that we can tailor the effects of cannabis to the needs of individual patients and consumers. Several years ago, I attended a seminar where a physician who was a cannabis advocate discussed the potential to match human DNA with the plant’s biological makeup. Scientists are now discovering that this could be true and are working to find the possible benefits for consumers and patients. This exciting development!
To be very clear, this science is in its infancy. There is currently a lot of scientific evidence on many isolated terpenes and some cannabinoids. However, not a lot is known regarding the effects of combinations of compounds, known as the ensemble (entourage) effect. Some terpenes, even when dominant, change their characteristics significantly when combined with other terpenes or cannabinoids. The method of consumption can also change the characteristics. Depending on the method of ingestion, some terpenes have the opposite effect when broken down in the liver. The point being that there are many combinations of the known terpenes and there could be hundreds more within the same plant. The good news is that we can trust professionals to guide the experience and we can also read about compounds that fit our specific needs. This potential is very exciting.
Following is a breakdown of what we know today about the most common terpenes found in the cannabis plant.
Sources: abundant in the cannabis plant, fruits, hops
Characteristics: aroma described as earthy, grassy, fruity, or combined earthy/berry
Action: When isolated, can produce a sedative effect if the concentration is greater than 0.5%. It can also act as an anti-inflammatory, anticarcinogenic or as a muscle relaxant. When combined with THC and CBD, it may have a neuroprotective quality, i.e., it may protect the brain.
Source: abundant in the cannabis plant and the rind of citrus fruit
Characteristics: has a fruity, citrus-like aroma
Action: As a dominant terpene, Limonene may produce feelings of silliness, euphoria, or general wellbeing. Because it interacts with the brain’s dopamine and serotonin receptors, it may act as an antidepressant or an anxiolytic (anti-anxiety). Further studies may find that it has antioxidant, anti-inflammatory or antacid effects, and may help to boost the immune system when used in combination with cannabinoids. Adding limonene to topical compounds seems to enhance absorption and improve the delivery of those compounds across the mucous membranes into the bloodstream.
Source: cannabis plants and pine needles
Characteristics: This is the first terpene to be produced by the cannabis plant and has an odor that is detected in the early stages of plant development.
Actions: The Japanese term, translated into English means “forest bathing”. Alpha Pinene can act as a bronchodilator, opening the airways and allowing for improved inhalation with better oxygen absorption. Improved oxygenation allows the brain to become more focused and alert. Medicinal properties that still need to be explored include possible use as anxiolytics, anti-inflammatories, antibiotics, or antiproliferatives in cancer care. Pinene may also counteract the side effects of high THC levels such as memory loss and anxiety.
Sources: turnips, turpentine, abundant in cannabis plants.
Characteristics: sharp diesel-like odor
Actions: Research done on isolated terpinolene has revealed that it has a sedative effect. However, when combined with THC, it has the opposite effect. This illustrates that isolated compound research doesn’t show the full picture of combined compounds (ensemble or entourage effect). More research may find that Terpinolene may also have anti-inflammatory, antioxidant, antifungal and antiproliferative uses. It may help to prevent atherosclerosis and coronary artery disease.
Sources: cloves, black pepper, cinnamon sticks
Characteristics: earthy, sweet, even spicy aroma similar to potpourri
Actions: Many medicinal properties are present due to its interaction with CB2 receptors. It may act as a muscle relaxant, an antidepressant or as an analgesic. When combined with THC, it can help to reduce nausea. Combined with CBD, it has an anti-inflammatory effect.
Sources: found in more than 200 plant types; abundant in lavender
Characteristics: has the characteristic scent of lavender; spicy aroma
Actions: Known to relieve stress and anxiety. Can have a sedative effect. There can be an antidepressant, analgesic or immune-enhancing effect. Studies are inconclusive, but it may enhance the anticonvulsive element when combined with CBD and THCA. This could be a significant development in the ongoing anticonvulsant cannabinoid research that has already received FDA approval. When ingested orally, linalool interacts with liver enzymes which may produce a different effect.
There is also a study that shows it could significantly reduce lung inflammation caused by cigarette smoke & could reduce the harm in inhaling cannabis smoke. https://www.sciencedirect.com/science/article/pii/S1567576915301089
Humulene (Alpha Caryophyllene, an isomer of Beta Caryophyllene)
Source: abundant in both hops and cannabis
Characteristics: grassy/earthy aroma
Actions: Produces drowsiness. It is also an effective pest repellant for plants. When combined, beta caryophyllene and Humulene seem to produce a 30% increase in the effect of anticancer proliferatives.
Source: being found in increasing numbers of cannabis strains, as well as other plants
Characteristics: Sweet, perfume-like aroma similar to perfumed cosmetics
Actions: May be an effective antifungal, anticonvulsant or antiproliferative. More research is needed to understand this terpene in particular. There are many documented properties that support its existence in nature, such as its role in the social regulation of honeybee colonies and its ability to improve a plant’s resistance to pests. Less is known about the human physiological experience.
This article has only scratched the surface of the science of terpenes and it should be noted that this is just a snapshot of what is contained in the cannabis plant. There are more than 200 terpenes that have been identified in the plant matrix and in the plant. Scientific research suggests that previously unknown terpenes are showing up as dominant within the cannabis plant, and the physiological effects on the human body are unknown. Testing isolates of these terpenes has shown that they are in direct conflict with anecdotal evidence shared by cannabis consumers. This could be due to the ensemble (entourage) effect, how they interact with other terpenes, and the body’s physiological response. We need to bridge the gap between anecdotal evidence and the scientific evidence. Research is now being done at a much faster pace because of the legalization in states across the country.
CNA Stores will continue to follow the research and provide updates as information becomes available.