The cannabis plant consists of a wide variety of chemicals and compounds. About 140 of these belong to a large class of aromatic organic hydrocarbons known as terpenes (pronounced tur-peens). You may have also heard people talk about terpenoids. The words terpene and terpenoid are increasingly used interchangeably, although these terms do have different meanings. The main difference between terpenes and terpenoids is that terpenes are hydrocarbons (meaning the only elements present are carbon and hydrogen); whereas, terpenoids have been denatured by oxidation (drying and curing the flowers) or chemically modified.

Terpenes are synthesized in cannabis in secretory cells inside glandular trichomes, and production is increased with light exposure. These terpenes are mostly found in high concentrations in unfertilized female cannabis flowers prior to senescence (the condition or process of deterioration with age). The essential oil is extracted from the plant material by steam distillation or vaporization. Many terpenes vaporize around the same temperature as THC (which boils at about 157°C), but some terpenes are more volatile than others. Terpenes also play an incredibly important role by providing the plant with natural protection from bacteria and fungus, insects and other environmental stresses.

It is well established that cannabis is capable of affecting the mind, emotions and behavior. The main psychotropic cannabinoid, delta-9-tetrahydrocannabinol (THC) has been intensely studied. However, many of the other cannabinoids, terpenoids and flavonoids found in medical marijuana that play a big role in boosting the therapeutic effect of cannabis remain understudied.

Terpenes are common constituents of flavorings and fragrances. Terpenes, unlike cannabinoids, are responsible for the aroma of cannabis. The FDA and other agencies have generally recognized terpenes as “safe.” Terpenes act on receptors and neurotransmitters; they are prone to combine with or dissolve in lipids or fats; they act as serotonin uptake inhibitors (similar to antidepressants like Prozac); they enhance norepinephrine activity (similar to tricyclic antidepressants like Elavil); they increase dopamine activity; and they augment GABA (the “downer” neurotransmitter that counters glutamate, the “upper”). However, more specific research is needed for improved accuracy in describing and predicting how terpenes in cannabis can be used medicinally to help treat specific ailments / health conditions.

Synergistic Effects

The Carlini et al study demonstrated that there may be potentiation (a form of synaptic plasticity that is known to be important for learning and memory) of the effects of THC by other substances present in cannabis. The double-blind study found that cannabis with equal or higher levels of CBD and CBN to THC induced effects two to four times greater than expected from THC content alone. The effects of smoking twice as much of a THC-only strain were no different than that of the placebo.

This suggestion was reinforced by a study done by Wilkinson et al to determine whether there is any advantage in using cannabis extracts compared with using isolated THC. A standardized cannabis extract of THC, CBD and CBN (SCE), another with pure THC, and also one with a THC-free extract (CBD) were tested on a mouse model of multiple sclerosis (MS) and a rat brain slice model of epilepsy.

Scientists found that SCE inhibited spasticity in the MS model to a comparable level of THC alone, and caused a more rapid onset of muscle relaxation and a reduction in the time to maximum effect than the THC alone. The CBD caused no inhibition of spasticity. However, in the epilepsy model, SCE was a much more potent and again more rapidly-acting anticonvulsant than isolated THC; however, in this model, the CBD also exhibited anticonvulsant activity. CBD did not inhibit seizures, nor did it modulate the activity of THC in this model. Therefore, as far as some actions of cannabis were concerned (e.g. anti-spasticity), THC was the active constituent, which might be modified by the presence of other components. However, for other effects (e.g. anticonvulsant properties) THC, although active, might not be necessary for the observed effect. Above all, these results demonstrated that not all of the therapeutic actions of cannabis herb is due to the THC content.

Dr. Ethan Russo further supports this theory with scientific evidence by demonstrating that non-cannabinoid plant components such as terpenes serve as inhibitors to THC’s intoxicating effects, thereby increasing THC’s therapeutic index. This “phytocannabinoid-terpenoid synergy,” as Russo calls it, increases the potential of cannabis-based medicinal extracts to treat pain, inflammation, fungal and bacterial infections, depression, anxiety, addiction, epilepsy and even cancer.

What are Flavonoids?

Flavonoids are one of the largest nutrient families known to scientists, and include over 6,000 already-identified family members. About 20 of these compounds, including apigenin, quercetin, cannflavin A and cannflavin B (so far unique to cannabis), β-sitosterol, vitexin, isovitexin, kaempferol, luteolin and orientin have been identified in the cannabis plant. Flavonoids are known for their antioxidant and anti-inflammatory health benefits, as well as their contribution of vibrant color to the many of the foods we eat (the blue in blueberries or the red in raspberries).

Some flavonoids extracted from the cannabis plant have been tested for pharmacological effects. The clinical findings are promising, but further research is needed to fully understand what role flavonoids play in the overall therapeutic effects of cannabis treatment, especially how they interact with cannabinoids by either synergistically enhancing them or reducing their effects.

The Terpene Wheel

Terpenes have been found to be essential building blocks of complex plant hormones and molecules, pigments, sterols and even cannabinoids. Most notably, terpenes are responsible for the pleasant, or not so pleasant, aromas of cannabis and the physiological effects associated with them. Patients will often ask to smell the cannabis when selecting their medicine. The idea is that certain aromas help identify different strains and their effects.

As the Casano et al study shows, medical marijuana strains can vary greatly from one source to another, and even from one harvest to another. Those with relatively high concentrations of specific terpenes do, however, make them easier to identify by their smell than other strains. Most agree that varieties that smell of musk or of clove deliver sedative, relaxing effects (high level of the terpene myrcene); piney smells help promote mental alertness and memory retention (high level of the terpene pinene); and lemony aromas are favored for general uplift in mood and attitude (high level of limonene).

Flavor wheel (source: GreenHouse Seeds Co.)

In a spectral analysis performed by Green House Seed Co., they were able to identify the terpenes in each of their strains, and developed a “flavor wheel” to help medical marijuana patients decide on their strain of choice based on the effects desired. Although one of the primary purposes of the wheel was to market different seeds for this particular company, the concept and vocabulary used is becoming an invaluable tool for medical marijuana patients, caregivers, and cultivators alike.

Since then, several companies have developed their own terpene and weed wheels, albeit for the same reasons — to market their own products or services — and that’s OK. By mapping out terpene profiles, we are able to predict and even manipulate the effects and medicinal value of varieties, giving breeders endless opportunities for developing new, highly-desired cannabis strains by basing breeding decisions on real analytical data. The more we are able to communicate using the same language, the easier it is for everyone to understand clearly what medicine they are getting. Check Out Mr Terps for Cannabis Terpenes for sale.

Terpenes in Cannabis

Myrcene

Myrcene, specifically β-myrcene, is a monoterpene and the most common terpene produced by cannabis (some varieties contain up to 60% of the essential oil). Its aroma has been described as musky, earthy, herbal – akin to cloves. A high myrcene level in cannabis (usually above 0.5%) results in the well-known “couch-lock” effect of classic Indica strains. Myrcene is found in oil of hops, citrus fruits, bay leaves, eucalyptus, wild thyme, lemon grass and many other plants.

Myrcene has some very special medicinal properties, including lowering the resistance across the blood to brain barrier, allowing itself and many other chemicals to cross the barrier easier and more quickly. In the case of cannabinoids (like THC), myrcene allows the effects of the cannabinoid to take effect more quickly. More uniquely still, myrcene has been shown to increase the maximum saturation level of the CB1 receptor, allowing for a greater maximum psychoactive effect.

Myrcene is a potent analgesic, anti-inflammatory, antibiotic and antimutagenic. It blocks the action of cytochrome, aflatoxin B and other pro-mutagenic carcinogens. The Bonamin et al study focused on the role of β-myrcene in preventing peptic ulcer disease. The study revealed that β-myrcene acts as an inhibitor of gastric and duodenal ulcers, suggesting it may be helpful in preventing peptic ulcer disease. Its sedative and relaxing effects also make it ideal for the treatment of insomnia and pain.

Since myrcene is normally found in essential oil from citrus fruit, many claim eating a fresh mango about 45 minutes before consuming cannabis will result in a faster onset of psycho activity and greater intensity. Be sure to choose a mango that is ripe otherwise the myrcene level will be too low to make a difference.

Pinene

Pinene is a bicyclic monoterpenoid. Akin to its name, pinene has distinctive aromas of pine and fir. There are two structural isomers of pinene found in nature: α-pinene and β-pinene. Both forms are important components of pine resin. α-pinene is the most widely encountered terpenoid in nature. Pinene is found in many other conifers, as well as in non-coniferous plants. It is found mostly in balsamic resin, pine woods and some citrus fruits. The two isomers of pinene constitute the main component of wood turpentine. Pinene is one of the principal monoterpenes that is important physiologically in both plants and animals. It tends to react with other chemicals, forming a variety of other terpenes (like limonene) and other compounds.

Pinene is used in medicine as an anti-inflammatory, expectorant, bronchodilator and local antiseptic. α-pinene is a natural compound isolated from pine needle oil which has shown anti-cancer activity and has been used as an anti-cancer agent in Traditional Chinese Medicine for many years. It is also believed that the effects of THC may be lessened if mixed with pinene.

Limonene

Limonene is a monocyclic monoterpenoid and one of two major compounds formed from pinene. As the name suggests, varieties high in limonene have strong citrusy smells like oranges, lemons and limes. Strains high in limonene promote a general uplift in mood and attitude. This citrusy terpene is the major constituent in citrus fruit rinds, rosemary, juniper and peppermint, as well as in several pine needle oils.

Limonene is highly absorbed by inhalation and quickly appears in the bloodstream. It assists in the absorption of other terpenes through the skin and other body tissue. It is well documented that limonene suppresses the growth of many species of fungi and bacteria, making it an ideal antifungal agent for ailments such as toenail fungus. Limonene may be beneficial in protecting against various cancers, and orally administered limonene is currently undergoing clinical trials in the treatment of breast cancer. Limonene has been found to even help promote weight-loss.

Plants use limonene as a natural insecticide to ward off predators. Limonene was primarily used in food and perfumes until a couple of decades ago, when it became better known as the main active ingredient in citrus cleaner. It has very low toxicity and adverse effects are rarely associated with it.

Caryophyllene

Beta-caryophyllene is a sesquiterpene found in many plants such as Thai basils, cloves, cinnamon leaves and black pepper, and in minor quantities in lavender. It’s aroma has been described as peppery, woody and/or spicy. Caryophyllene is the only terpene known to interact with the endocannabinoid system (CB2). Studies show β–caryophyllene holds promise in cancer treatment plans. Research shows shows that β–caryophyllene selectively binds to the CB2 receptor and that it is a functional CB2 agonist. Further, β–caryophyllene was identified as a functional non-psychoactive CB2 receptor ligand in foodstuff and as a macrocyclic anti-inflammatory cannabinoid in cannabis.

The Fine/Rosenfeld pain study demonstrates that other phytocannabinoids in combination, especially cannabidiol (CBD) and β-caryophyllene, delivered by the oral route appear to be promising candidates for the treatment of chronic pain due to their high safety and low adverse effects profiles.

The Horváth et al study suggests β-caryophyllene, through a CB2 receptor dependent pathway, may be an excellent therapeutic agent to prevent nephrotoxicity (poisonous effect on the kidneys) caused by anti-cancer chemotherapy drugs such as cisplatin.

The Jeena, Liju et al study investigated the chemical composition of essential oil isolated from black pepper, of which caryophyllene is a main constituent, and studied its pharmacological properties. Black pepper oil was found to possess antioxidant, anti-inflammatory and antinociceptive properties. This suggests that high-caryophyllene strains may be useful in treating a number of medical issues such as arthritis and neuropathy pain.

Beta-caryophyllene is used especially in chewing gum when combined with other spicy mixtures or citrus flavorings.

Linalool

Linalool is a non-cyclic monoterpenoid and has been described as having floral and lavender undertones. Varieties high in linalool promote calming, relaxing effects.

Linalool has been used for centuries as a sleep aid. Linalool lessens the anxious emotions provoked by pure THC, thus making it helpful in the treatment of both psychosis and anxiety. Studies also suggest that linalool boosts the immune system; can significantly reduce lung inflammation; and can restore cognitive and emotional function (making it useful in the treatment of Alzheimer’s disease).

As shown by the Ma, J., Xu et al study, linalool may significantly reduce lung inflammation caused by cigarette smoke by blocking the carcinogenesis induced by benz[α]anthracene, a component of the tar generated by the combustion of tobacco. This finding indicates limonene may be helpful in reducing the harm caused by inhaling cannabis smoke.

Linalool boosts the immune system as it directly activates immune cells through specific receptors and/or pathways. The Sabogal-Guáqueta et al study suggests linalool may reverse the histopathological (the microscopic examination of biological tissues to observe the appearance of diseased cells and tissues in very fine detail) hallmarks of Alzheimer’s Disease and could restore cognitive and emotional functions via an anti-inflammatory effect.

The Environmental Protection Agency has approved its use as a pesticide, flavor agent and scent. It is used in a wide variety of bath and body products and is commonly listed under ingredients for these products as beta linalool, linalyl alcohol, linaloyl oxide, p-linalool and alloocimenol. Its vapors have been shown to be an effective insecticide against fruit flies, fleas and cockroaches.

Linalool has been isolated in several hundred different plants. The Lamiaceae plant and herb family, which includes mints and other scented herbs, are common sources. The Lauraceae plant family, which includes laurels, cinnamon, and rosewood, is also a readily available source. The Rutaceae family, which contains citrus plants, is another viable source. Birch trees and several different plant species that are found in tropical and boreal climate zones also produce linalool. Although technically not plants, some fungi produce linalool, as well. Linalool is a critical precursor in the formation of Vitamin E.

Terpinolene

Terpinolene is a common component of sage and rosemary and is found in the oil derived from Monterey cypress. Its largest use in the United States is in soaps and perfumes. It is also a great insect repellent. Terpinolene is known to have a piney aroma with slight herbal and floral nuances. It tends to have a sweet flavor reminiscent of citrus fruits like oranges and lemons.

Terpinolene has been found to be a central nervous system depressant used to induce drowsiness or sleep or to reduce psychological excitement or anxiety. Further, terpinolene was found to markedly reduce the protein expression of AKT1 in K562 cells and inhibited cell proliferation involved in a variety of human cancers.

Camphene

Camphene, a plant-derived monoterpene, emits pungent odors of damp woodlands and fir needles. Camphene may play a critical role in cardiovascular disease.

The Vallianou et al study found camphene reduces plasma cholesterol and triglycerides in hyperlipidemic rats. Given the importance that the control of hyperlipidemia plays in heart disease, the results of this study provide insight into to how camphene might be used as an alternative to pharmaceutical lipid lowering agents which are proven to cause intestinal problems, liver damage and muscle inflammation. This finding alone warrants further investigation.

Camphene is a minor component of many essential oils such as turpentine, camphor oil, citronella oil and ginger oil. It is used as a food additive for flavoring, and also used in the preparation of fragrances. It is produced industrially by catalytic isomerization of the more common α-pinene.

Terpineol

α-Terpineol, terpinen-4-ol, and 4-terpineol are three closely related monoterpenoids. The aroma of terpineol has been compared to lilacs and flower blossoms. Terpineol is often found in cannabis varieties that have high pinene levels, which unfortunately mask the fragrant aromas of terpineol.

Terpineol, specifically α-terpineol, is known to have calming, relaxing effects. It also exhibits antibiotic, AChe inhibitor and antioxidant antimalarial properties.

Phellandrene

Phellandrene is described as pepperminty, with a slight scent of citrus. Phellandrene is believed to have special medicinal values. It has been used in Traditional Chinese Medicine to treat digestive disorders. It is one of the main compounds in turmeric leaf oil, which is used to prevent and treat systemic fungal infections.

Phellandrene is perhaps the easiest terpene to identify in the lab. When a solution of phellandrene in a solvent (or an oil containing phellandrene) is treated with a concentrated solution of sodium nitrate and then with a few drops of glacial acetic acid, very large crystals of phellandrene nitrate speedily form.

Phellandrene was first discovered in eucalyptus oil. It wasn’t until the early 1900s that it was actually constituted and shown that phellandrene from eucalyptus oil contained two isomeric phellandrene (usually referred to as α-phellandrene and β-phellandrene), and on oxidation with potassium permanganate gave distinct acids, concluding that the acids had been derived from two different isomeric phellandrene. Before that, phellandrene was mistaken for pinene or limonene. Today, we are aware of many essential oils where phellandrene is present. It is, however, a somewhat uncertain terpene as it can only be detected in the oils of some species, especially in Eucalypts, at particular times of the year.

Phellandrene can be found in a number of herbs and spices, including cinnamon, garlic, dill, ginger and parsley. A number of plants produce β-phellandrene as a constituent of their essential oils, including lavender and grand fir. The recognizable odors of some essential oils depend almost entirely upon the presence of phellandrene. Oil of pepper and dill oil are composed almost entirely of phellandrene. The principal constituent in oil of ginger is phellandrene. Phellandrene, particularly α-phellandrene, is absorbed through the skin, making it attractive for use in perfumes. It is also used as a flavoring for food products.

Carene

Delta-3-carene is a bicyclic monoterpene with a sweet, pungent odor. It is found naturally in many healthy, beneficial essential oils, including cypress oil, juniper berry oil and fir needle essential oils. In higher concentrations, delta-3-carene can be a central nervous system depressant. It is often used to dry out excess body fluids, such as tears, mucus, and sweat.

It is nontoxic, but may cause irritation when inhaled. Perhaps high concentrations of delta-3-carene in some strains may be partially responsible for symptoms of coughing, itchy throat and eye afflictions when smoking cannabis.

Delta-3-carene is also naturally present in pine extract, bell pepper, basil oil, grapefruit and orange juices, citrus peel oils from fruits like lemons, limes, mandarins, tangerines, oranges and kumquats.

Carene is a major component of turpentine and is used as a flavoring in many products.

Humulene

Humulene is a sesquiterpene also known as α-humulene and α–caryophyllene; an isomer of β–caryophyllene. Humulene is found in hops, cannabis sativa strains, and Vietnamese coriander, among other naturally occurring substances. Humulene is what gives beer its distinct ‘hoppy’ aroma.

Humulene is considered to be anti-tumor, anti-bacterial, anti-inflammatory, and anorectic (suppresses appetite). It has commonly been blended with β–caryophyllene and used as a major remedy for inflammation. Humulene has been used for generations in Chinese medicine. It aids in weight loss by acting as an appetite suppressant.

Pulegone

Pulegone, a monocyclic monoterpenoid, is a minor component of cannabis. Higher concentrations of pulegone are found in rosemary. Rosemary breaks down acetylcholine in the brain, allowing nerve cells to communicate more effectively with one another.

An ethnopharmacology study indicates pulegone may have significant sedative and fever-reducing properties. It may also alleviate the side effects of short-term memory loss sometimes associated with higher levels of THC.

Pulegone has a pleasant peppermint aroma and is considered to be a strong insecticide.

Sabinene

Sabinene is a bicyclic monoterpene whose aromas are reminiscent of the holidays (pines, oranges, spices). Results of an ongoing study by Valente et al suggest that sabinene should be explored further as a natural source of new antioxidant and anti-inflammatory drugs for the development of food supplements, nutraceuticals or plant-based medicines.

Sabinene occurs in many plants, including Norway spruce, black pepper, basil and Myristica fragrans (an evergreen indigenous to the Moluccas)—the Spice Islands of Indonesia. The seeds of the Myristica fragrans are the world’s main source of nutmeg. Sabinene exists as (+)- and (–)-enantiomers.

Geraniol

Geraniol produces a sweet, delightful smell similar to roses. This makes geraniol a popular choice for many bath and body products. It is also known to be an effective mosquito repellant. Medically, geraniol shows promise in the treatment of neuropathy.

Terpenes, terpenoids, terps. Whatever you call them, these compounds in cannabis that give it distinctive aromas and flavors are popping up in consumer products everywhere. In US states where medical and recreational cannabis is legal, companies are spiking tinctures, vaping oils, lotions, foods, and beverages with terpenes, along with cannabinoids like tetrahydrocannabinol (THC) and cannabidiol (CBD). In other places, companies are marketing similar products minus the THC, with labels claiming “whole plant” medicine or “full spectrum” CBD.

The idea is that terpenes enhance the health benefits of the products either alone or synergistically with other terpenes, THC, CBD, and other minor cannabinoids found in cannabis. Most research has focused on the health effects of individual terpenes. For example, linalool, a terpene also found in lavender, provides antianxiety effects. α-Pinene, which is also produced in rosemary, can be invigorating and lead to mental alertness. Much less is known about how terpenes work together and in combination with cannabinoids.

“We have barely begun to understand the therapeutic potential of cannabis,” says Ethan Russo, a neurologist and director of R&D at the International Cannabis and Cannabinoids Institute, based in the Czech Republic. “We haven’t taken the steps that are required to really harness the abilities of some of these minor cannabinoids, particularly in conjunction with optimized terpenoid profiles.”

Russo prefers the term terpenoid over terpenes because “terpenes are hydrocarbons. Terpenoids may have oxygen or other elements, so terpenoid is actually the more encompassing term,” he says. “But when people are speaking cannabis, they are pretty much synonymous.”­

Related: Cannabis research stalled by federal inaction

A nebulous understanding of how terpenes interact with other chemicals in cannabis, however, isn’t stopping cannabis companies from jumping into terpenes. Manufacturers are getting creative and adding the flavorful compounds to a wide array of products to try to mimic—or enhance—terpene profiles found in cannabis flowers.

Plants create terpenes to protect themselves from predators or to lure pollinators. Each different strain or chemical variety of cannabis, sometimes called a chemovar, has its own signature of terpenes and cannabinoids. There are hundreds, if not thousands, of these chemovars, each with random-sounding names that often allude to the kind of sensory experience a user may feel. For example, Lemon Kush is high in limonene, a terpene also found in citrus peels that is known for its mood-elevating and antibacterial properties. Blue Dream is high in myrcene, known for its relaxing and sedative effects. Sour Diesel is high in both myrcene and limonene, a combination known for its energizing and stress-relieving effects.

Just because two varieties of cannabis are sold under the same name, however, doesn’t mean they have the same chemical profile. Most of the time they do not.

A huge number of variables affect the terpene profile of plants, says Amber Wise, scientific director at Medicine Creek Analytics, a cannabis-testing lab in Washington State. If plants with the same genetic makeup are grown outdoors versus indoors, “you can end up with different terpene profiles at the end because temperature, growing medium, nutrients, sunlight, all kinds of things affect the terpene profile of plants,” Wise says.

Terpene therapeutics

The strong-smelling chemicals in cannabis products may be beneficial to your health—and they may also come from other sources.

α-Bisabolol

Aromas and flavors: Coconut, fruity, nutty
Health effects: Antibacterial, anti-inflammatory

β-Caryophyllene

Aromas and flavors: Clove, dry, spicy, woody
Health effects: Antimicrobial, anti-inflammatory, neuroprotective

α-Humulene

Aromas and flavors: Bitter, floral, peppery, woody
Health effects: Antibacterial, anti-inflammatory

(+)-Limonene

Aromas and flavors: Citrusy, sweet
Health effects: Antibacterial, mood elevation, stress relief

Linalool

Aromas and flavors: Floral, rose, woody
Health effects: Antianxiety, sedative

Myrcene

Aromas and flavors: Celery-like, herbaceous, turpentine- like, woody
Health effects: Analgesic, sedative, relaxing

α-Pinene

Aromas and flavors: Cool, fresh, herbal, piney, turpentine- like
Health effects: Alertness, possible memory retention

β-Pinene

Aromas and flavors: Green hay, piney, spicy, woody
Health effects: Anti-inflammatory, bronchodilator

Terpinolene

Aromas and flavors: Fresh, lemon peel, sweet
Health effects: Antibacterial, antifungal, possible sedative

Source: The Werc Shop. Note: Health effects have largely been studied for individual chemicals in isolation, not in mixtures.

David Heldreth, a longtime cannabis grower and medical-cannabis patient, began nearly a decade ago to investigate how various growing conditions affect the composition of cannabis. He patented a series of lighting changes and fertilizer, plant growth hormone, and enzyme treatments that increase the production of minor cannabinoids, such as cannabigerol and cannabichromene, as well as specific terpenes.

Today, Heldreth is the chief science officer at True Terpenes, an Oregon-based company that markets terpenes to companies that reformulate them into various consumer goods. Companies are adding True Terpenes’ formulations to edibles such as chocolate, beverages such as soda and beer, and various skin lotions, Heldreth says. Manufacturers are also adding such terpene formulations to vaping oils that contain cannabinoids.

Demand for terpenes is booming in the US now that CBD from hemp is legal across the country. It is currently too expensive to harvest and extract CBD from hemp flowers, so companies are using the entire plant, including the leaves and stalks, Heldreth says.

Many companies use ethanol to extract CBD from the whole plant material. When the ethanol is removed, terpenes are lost through volatilization. So companies often reintroduce terpenes into their final products. Unfortunately, “there aren’t any extra terpenes around from cannabis,” Heldreth says.

True Terpenes sources its terpenes from other natural products, such as getting linalool from lavender and limonene from citrus. The company works with cannabis growers to obtain analytical data on terpenes in various cannabis strains. It then develops formulations that contain about 40 terpenes at percentages that mimic the chemical signatures of popular cannabis strains. The formulations are mixtures of essential oils that are generally recognized as safe by food regulators. Some of the products also contain refined coconut oil.

Cannabinoids are not water soluble, and formulation strategies differ for edible and topical products compared with those intended for inhalation. In aqueous products like beverages, cannabinoids are often encapsulated in micelles and microemulsions using proprietary methods developed by pharmaceutical companies.We don’t know anything about vaping terpenes or the degradation products that they might form after high heat exposure.Amber Wise, scientific director, Medicine Creek Analytics

Vaping oils require a thinning agent, such as propylene glycol, poly(ethylene glycol), or vegetable glycerin—the same chemicals used in e-cigarette liquids. Some companies use medium-chain triglycerides from refined coconut oil.

When these thinning agents are heated, they emit formaldehyde, warns Jeff Raber, cofounder and CEO of the Werc Shop, a California-based cannabis contract manufacturing and testing firm. It is not something you want to inhale, he says.

The Werc Shop was granted a US patent earlier this year related to a thinning agent made up of the terpene phytol and related compounds. The company now markets a formulation called Nexus 2.0 that combines phytol with other terpenes and compounds found in cannabis. The formulation improves the stability, performance, and inhalation safety of vaping products, Raber claims.

Related: Symrise makes synthetic cannabidiol

The Nexus formulation also aims to offer the same taste and effect that plant material does. “Our terpene formulations can comprise more than 50 components,” Raber says. “They are what we call ‘true to plant.’ ”

The concentration of terpenes in vaping oil typically ranges from 5 to 15%, depending on the preferred end formulation, Raber says. If the concentration is too high, “it can actually sting your lips or tongue,” he says. “It can taste bad if not done well.”

Some people can also develop allergies, such as skin and inhalation sensitivities, to terpenes. Many of the allergens in fragrances are terpenes, says Julie Kowalski, chief scientific officer at Trace Analytics, a cannabis-testing lab in Washington State. People need to think about allergies, particularly “when they are formulating products where they put in artificially high amounts of terpenes,” she says.

Most companies aim to replicate the terpenes in cannabis flowers at ratios that occur naturally. But not all manufacturers are doing it well.

“We’ve seen concentrations of up to 20% terpenes in some formulations,” Wise says. Such high levels of terpenes are “terrifying from a public health standpoint,” she says. Terpenes are typically found in cannabis flowers at levels of 2–5%.

“We don’t know anything about vaping terpenes or the degradation products that they might form after high heat exposure,” Wise says. Terpenes are highly reactive molecules that isomerize and interact with O₂, she notes. But “it is a big unknown as to what happens when you heat them up, smoke them, or vape them,” she says. Variability of vape-oil composition makes it particularly challenging to study terpenes’ health effects.

Olala, a recreational-cannabis company in Washington, started out making vape oils. Today, the company’s biggest source of revenue is cannabis beverages—sodas, coffee, sparkling water, and terpene tonics—says the firm’s president, Randy Reed.

The company focuses on being a “best-in-class-type manufacturer, whether it be making beverages, vape oils, topicals, or capsules,” Reed says. “We don’t know what direction the cannabis industry is going. You’ve got to be flexible.” To that end, Olala has developed a manufacturing facility that can pivot quickly and change to give consumers the products they want, Reed says. That includes making products with specific terpene profiles, as well as THC and other cannabinoids.

Related: Hemp growing pains

Olala products start with fresh cannabis flowers. The company extracts all the cannabinoids and terpenes it can using a multiphase carbon dioxide extraction technique with ethanol modifiers. The method involves using subcritical CO₂ to fractionate off the terpenes, followed by supercritical CO₂ to pull out cannabinoids.

Each fraction is characterized and quantified, so the company has full control over how much of each ingredient is added back into its products. “For our edibles, we don’t want all those terpenes in there,” Reed says. The smell and taste of the terpenes, which can be quite bitter, would overpower whatever other flavor is in the product—for example, orange cream or lemon lime in a soda—he says.

Other Olala products, such as vape oils and terpene tonics, which are formulated to taste like specific cannabis flowers, have higher terpene concentrations. According to anecdotal evidence, terpene tonics that are high in myrcene or linalool will make you feel more relaxed, Reed says. Other terpene tonics that are high in α-pinene and terpinolene will give you a more uplifting effect, he adds. The terpene tonics are “kind of a craft maker thing,” Reed says. “You have a feel for the various chemovars or the chemical profiles of the flower.”

Olala’s inclusion of THC in its products differentiates it from much of the CBD industry, which markets products for wellness rather than recreation. So-called full-spectrum or whole-plant CBD tinctures without THC are increasingly popular. These extracts contain several minor cannabinoids in addition to CBD. The problem is there are “reportedly over 300 online CBD hemp companies,” says Bonni Goldstein, medical director of Canna-Centers, a California-based medical cannabis practice. There is no way to tell what is in those bottles other than to ask the company for a certificate of analysis or pay for a lab to test a sample, she says. There are good-quality CBD products and “garbage,” she warns.

Goldstein treats children with epilepsy, cancer, severe attention deficit hyperactivity disorder, debilitating Tourette’s syndrome, and mental health disorders like anxiety, depression, and self-injury. She emphasizes the importance of accurate labeling on CBD oils when they are used for medical purposes.

Last year, the US Food and Drug Administration approved the first pure CBD drug, Epidiolex, for treating seizures in children with two rare disorders. The drug, manufactured by GW Pharmaceuticals, does not contain any other cannabinoids or terpenes derived from cannabis.

Epidiolex gives certainty in CBD dosing, but researchers in Brazil have found that it is less effective than equivalent doses of CBD in extracts that also contain the full array of cannabinoids and terpenes found in cannabis flowers. They reported that it takes a lot less, about 22% of the dose of pure CBD, to treat severe seizures with whole-plant CBD extracts (Front Neurol. 2018, DOI: 10.3389/fneur.2018.00759).

“Because of the synergy, even a touch of THC or anticonvulsant terpenoids such as linalool can make a difference between control and lack of it” with respect to seizures, the International Cannabis and Cannabinoids Institute’s Russo says. “If you need five times as much of the pure-compound CBD, it doesn’t mean that CBD is bad medicine. It means that the plant does it better.”

Whole-plant extracts not only are more effective but also have fewer side effects than pure CBD at higher doses, Russo says. The bottom line, he says, is that “whole-cannabis extracts are going to have an advantage over pure compounds in almost every instance.”

Consequently, some parents of children with chronic conditions continue to use CBD oils rather than Epidiolex. Such oils may be whole-plant extracts or they may be CBD extracts with terpenes added. People who buy CBD oils online sometimes pay for the oils to be tested by private laboratories, Goldstein says. In some cases, labs reported high levels of pesticides, lead, and isopropyl alcohol, she says. In other cases, the amount of CBD in the bottle was too low for treating a pediatric patient with epilepsy.

These problems drive many families to make their own oils by purchasing raw cannabis flowers from a dispensary, Goldstein says. Doing so allows them to control the quality as well as to try numerous varieties that are not available as prefabricated manufactured oil, she notes. Each variety has subtly different effects, and some work better than others for particular patients.

Using oils or extracts from cannabis flowers directly is the best way to achieve health benefits from cannabis, some argue. “There is a purist argument that you should keep cannabis together” and not introduce terpenes from other natural products, says Toby Astill, global food market manager at the instrumentation company PerkinElmer. But it probably doesn’t matter where the terpenes come from, assuming they are of food-grade quality and product manufacturers can match the profiles found in cannabis flowers. “At the end of the day, if you analytically know what your terpene is, it is the same chemistry from either source,” he says. “It does work both ways.”

A BRIEF DESCRIPTION

Terpenes are the organic compounds responsible for creating the unique aroma of each individual cannabis plant. Terpenes do more than determine the scent finger print, they also provide therapeutic benefits like their cannabinoid partners, THC and CBD. Formed from the same shiny, resinous trichomes as cannabinoids, cannabis terpenes also bind to the same endocannabinoid receptors located throughout the brain and body. For example, depending upon which receptors they react with, different terpenes may help to induce sleep and relax muscles while others reduce stress and elevate mood, or reduce inflammation and increase energy.

When terpenes work together with cannabinoids, in a process known as the entourage effect, the therapeutic potentials increase dramatically. Terpenes can also modify how much of each cannabinoid is absorbed. This means the presence of certain terpenes can increase or decrease the amount of the psychoactive cannabinoid THC is absorbed, effectively controlling the potency. Consequently, a strain of medical cannabis with the perfect mix of terpenes and cannabinoids could be the equivalent of a hand tailored suit, designed to treat a particular disease or condition.

Select one of the terpenes from the options below to learn about each one’s unique aroma and which medicinal benefits it may provide to treat your condition.

Myrcene

TERPENE PROFILE

Myrcene is the most prevalent of the more than 200 identified terpenes which form the building blocks of medical cannabis, hogging as much as 50 percent of the terpene volume at one time. Responsible for the earthy, spicy balsamic, and clove aromas, myrcene also plays a precursory role in the formation of several other terpenes. myrcene can also be found in hops, mango, lemongrass and basil.

Also playing a role in whether a particular strain displays sativa or indica characteristics, myrcene adds to the robust medical efficacy of cannabis. According to research, myrcene is attributed to producing the following therapeutic benefits:

Linalool

TERPENE PROFILE

Linalool is one of the more than 200 fragrant chemical compounds, known as terpenes, that are the foundation for the pungent aroma and medicinal value of cannabis. In medical cannabis plants, linalool is typically responsible for producing a floral, spicy or woody aroma. With documented use dating back thousands of years, linalool is one of the oldest known sedatives, or sleep aids, in the world. Linalool, like cannabinoids THC or CBD, is formed within the shiny resinous glands covering cannabis flowers, called trichomes. Also found in some citrus, birch, rosewood, laurels and coriander, linalool is arguably most recognizable in lavender.

Conferring more than just strong sedative properties, research shows linalool to supply the following medical benefits in cannabis:

Pinene

TERPENE PROFILE

Formed within the shiny resinous glands that cover cannabis flowers, called trichomes, pinene is one of the hundreds of terpenes that serve as the foundation for the pungent aroma and medical efficacy of cannabis. The most commonly occurring terpene among all plants, pinene, comes in two different varieties — alpha and beta. Alpha-pinene secretes aromas of pine needles or rosemary, while beta-pinene produces scents of hops, dill, parsley, or basil. Pinene is also found in turpentine, conifer trees, and orange peels.

Contributing strong medical benefits to the synergistic relationship between terpenes and cannabinoids, research reveals that pinene provides the following therapeutic qualities:

Limonenes

TERPENE PROFILE

Limonene is one of the more than 200 identified medical cannabis terpenes that works side by side with cannabinoids to provide the therapeutic benefits in the treatment of so many different conditions and ailments. Known for secreting the familiar smell of citrus, limonene can translate into the lemon, orange, grapefruit, lime, mint, rosemary or even juniper aroma. It is exactly the same chemical that provides fruits like oranges, lemons and limes with a citrus scent.

More than just a pungent aroma, limonene makes a powerful contribution to the impressive medical efficacy of cannabis. Research shows limonene to produce the following effects: