What are cannabis terpenes?
There are many varieties and strains of cannabis. Everyone has their favorites. OG Kush, Headband, Sour Diesel, Flo, Lemon Thai, Super Silver Haze ... Some strains are energizing, some are sedating; some are better for pain, others for inspiration.
A couple hits of high-THC herb, by whatever name it’s called, will get you good and stoned. But it’s not the amount of delta-9-tetrahydrocannabinol that accounts for the particular properties of each strain. Nor are the minuscule quantities of cannabidiol (CBD) or the hundred or so “minor” cannabinoids a key factor in most strains. With few exceptions, the THC levels are lofty, while the other cannabinoids barely register their presence, according to labs that test samples for growers and dispensaries in states where medical marijuana is legal.
So if the THC levels are high in each strain, and if cannabinoid are only present at a base level, what causes one strain to be different from another? Why are there so many strains? So many variations? So many properties?
Some believe that terpenes are key, at least in terms of their modifying impact on THC. Terpenes, or terpenoids, are the compounds in cannabis that give the plant its unique smell. THC and the other cannabinoids have no odor, so marijuana’s compelling fragrance depends on which terpenes predominate. It’s the combination of terpenoids and THC that endows each strain with a specific psychoactive flavor.
Terpene-infused resin with 50 percent THC can be more potent by dry weight than an equivalent amount of pure THC. Whereas THC and cannabinoids are only found in marijuana, terpenes are more common throughout nature. It is the combination of certain terpenes with certain THC/cannabinoids that give certain strains their particular characteristics.
Alpha-pinene (essential pine oil), the most common terpene in the plant world and one often found in cannabis, is a bronchodilator potentially helpful for asthmatics. Pinene also promotes alertness and memory retention by inhibiting the metabolic breakdown of acetylcholinesterase, a neurotransmitter in the brain that stimulates these cognitive effects.
Myrcene, another terpene present in numerous cannabis varietals, is a sedative, a muscle relaxant, a hypnotic, an analgesic (painkiller) and an anti-inflammatory compound. This musky terpene contributes mightily to the infamous “couch-lock” experience, Russo maintains.
Limonene, a major terpene in citrus as well as in cannabis, has been used clinically to dissolve gallstones, improve mood and relieve heartburn and gastrointestinal reflux. Limonene has been shown to destroy breast-cancer cells in lab experiments, and its powerful antimicrobial action can kill pathogenic bacteria. (Lemon Kush, anyone?)