Cannabis Terpenes and Their Effects

Tricomb structures on a cannabis plant.

Around 200 terpenes have been found in cannabis, but only a few of these odiferous oily substances appear in amounts substantial enough to be noteworthy, or nose worthy, as it were. Among them are monoterpenes, diterpenes, and sesquiterpenes, which are characterized by the number of repeating units of a 5-carbon molecule called isoprene, the structural hallmark of all terpenoid compounds. The terpenes in marijuana have given the plant an enduring, evolutionary advantage. Pungent terpenoid oils repel insects and animal grazers; others prevent fungus.

Terpenes, it turns out, are healthy for people as well as plants. A September 2011 report by Dr. Ethan Russo in the British Journal of Pharmacologydiscussed the wide-ranging therapeutic attributes of terpenoids, which are typically lacking in “CBD-only” products.

Beta-caryophyllene, for example, is a sesquiterpene found in the essential oil of black pepper, oregano, and other edible herbs, as well as in various cannabis strains and in many green, leafy vegetables. It is gastro-protective, good for treating certain ulcers, and offers great promise as a therapeutic compound for inflammatory conditions and auto-immune disorders because it binds directly to the peripheral cannabinoid receptor known as “CB2.”

In 2008, the Swiss scientist Jürg Gertsch documented beta-caryophyllene’s binding affinity for the CB2 receptor and described it as “a dietary cannabinoid.” It is the only terpenoid known to directly activate a cannabinoid receptor. And it’s one of the reasons why green, leafy vegetables are so healthy to eat.

Terpenoids and cannabinoids both increase blood flow, enhance cortical activity, and kill respiratory pathogens, including MRSA, the antibiotic-resistant bacteria that in recent years has claimed the lives of tens of thousands of Americans. Dr. Russo’s article reports that cannabinoid-terpenoid interactions “could produce synergy with respect to treatment of pain, inflammation, depression, anxiety, addiction, epilepsy, cancer, fungal and bacterial infections.”

The terpenoid profile can vary considerably from strain to strain. Patients who abandon a suitable strain for one with higher THC and/or CBD content may not get more relief if the terpenoid profile is significantly different.