Everything you need to know about cannabis terpenes

What are terpenes?

Terpenes (pronounced tur-peens) are the organic, aromatic compounds found in plants in the form of oils. Essentially, they are what gives a plant its unique flavour and aroma. When it comes to cannabis plants, terpenes are contained in the trichomes of female cannabis plants in the form of sticky resin glands. Cannabis plants contain more than 150 types of terpenes, each responsible for the aromatic diversity of the wide range of cannabis cultivars and strains available. 

Until recently, much of the cannabis industry has been focused almost solely on the therapeutic qualities of cannabinoids like THC and CBD. But, as our knowledge of terpenes continues to grow and cannabis science expands, it’s becoming increasingly apparent that these aromatic compounds are medicinal powerhouses in their own right. Beyond just influencing the cannabis plant’s unique taste and smell, terpenes play a significant role in the therapeutic effects of cannabis by interacting with cannabinoids and other cannabis compounds to create subtle differences in our experience.

It all comes down to synergy. That is, multiple elements of cannabis working together to amplify each individual element’s effect. This allows for the overall effect of the plant to be greater than the sum of its individual parts (this phenomenon is known as the ‘entourage effect’¹). When cannabinoids like THC and CBD are paired with other cannabis compounds such as terpenes (or certain concentrations of them) they create or emphasise particular medicinal or other types of effects, opening up a world of therapeutic combinations and medicinal purposes that researchers are beginning to explore.

What do terpenes do and what are their effects?

Throughout history, humans have been harnessing the wide range of aromas and properties of terpenes for various purposes, including medicinal. Different terpenes have different effects on the mind and body, with potential capabilities ranging from antibacterial and antifungal to anticancer and pain relieving², to name a few. The potential medicinal properties of these aromatic compounds and the way terpenes interact with the endocannabinoid system are still being explored and we hope to see more medical research in the near future.

Ever used the scent of lavender to help you drift off to sleep? You have the terpene linalool to thank for that effect! Studies have shown that linalool aids sedation and relaxation while reducing aggression and hostility. Does the smell of citrus have an uplifting effect on your mood? That’s thanks to the terpene limonene, which is known as a natural antidepressant (among its many other medicinal properties)².

These are just some of the potential therapeutic effects and benefits of terpenes, many of which can be found in cannabis treatments:

• Antiviral: there are a number of terpenes which demonstrate antiviral capabilities, including beta-pinene and limonene⁴, as well as caryophyllene, camphor, and carvone⁵.
• Antidepressant: 25% of modern-day antidepressant drugs are formulated using herbal extracts that contain terpenes, including linalool and beta-pinene².
• Pain relieving: like some cannabinoids, terpenes including humulene, geraniol, linalool, and β-pinene are capable of activating the body’s CB1 receptors (a component of the endocannabinoid system which influences pain perception). One 2021 study combined these terpenes with cannabinoids and found the pain-relieving effects of the cannabinoids to be amplified without an increase in negative side effects. These findings support the entourage effect theory mentioned earlier⁶.
• Anticancer: terpenes like limonene (which may have significant anticancer and antitumor properties⁷), as well as pinene, camphor, terpinene, and beta-myrcene may help inhibit the activity or growth of cancer cells⁸.
• Antimicrobial: terpenes like alpha-bisabolol, geraniol, menthol, eucalyptol, and terpinolene may display antimicrobial activity⁹ which could help in stopping the progression of harmful microorganisms.

Much more research is needed (especially in humans) to uncover the full therapeutic potential of terpenes¹⁰. However preliminary research on medicinal properties and a longstanding history of terpenes being used in traditional medicine indicates that these compounds may have powerful health benefits yet to be explored.

Do terpenes make your patients high?

Terpenes found in cannabis plants aren’t intoxicating on their own, and they won’t make your patients feel high in the way that the cannabinoid THC might. However, some terpenes are still considered to be psychoactive because they have an effect on the brain (such as making people feel relaxed, uplifted, or less anxious). 

While cannabis terpenes won’t get patients high on their own, these aromatic compounds may still alter the effects of intoxicating cannabinoids like THC. THC is the cannabinoid responsible for the high feeling many experience with cannabis use. Some people believe that different combinations of cannabinoids and terpenes may alter and even mitigate the undesirable effects that some THC users experience, like anxiety and intoxication. There is also some evidence that terpenes enhance the existing therapeutic properties of cannabinoids – such as pain relieving⁶ and antidepressant² effects – when they are taken together.

How do terpenes differ from cannabinoids (THC & CBD)?

Cannabinoids and terpenes are both organic compounds found in cannabis plants – and both have varying effects on the mind and body – but terpenes are not cannabinoids. Let’s explore the differences between the two:

Cannabinoids

• Cannabinoids are a diverse array of molecules found within the cannabis plant, some other plants, and the human body. 
• Phytocannabinoids like THC and CBD are the most common you’ll hear about, and both are found within the cannabis plant. They are largely responsible for the effects patients experience when they consume cannabis, including psychoactive, therapeutic, and other effects. 
• Cannabinoids interact with the endocannabinoid system in varying ways to produce effects within the mind and body.
• Cannabinoids are heavily regulated in Australia and require a prescription in most cases.
• Cannabinoids like THC are capable of producing an intoxicating effect on the user.

Terpenes

• Terpenes are also organic compounds found within the cannabis plant, but with different effects and properties to cannabinoids. 
• Terpenes influence the aroma and flavour of cannabis (alongside Flavonoids and Volatile Sulphur Compounds (VSCs)¹¹) while cannabinoids do not. 
• Terpenes are found in abundance in almost all plants, while cannabinoids exist mainly in cannabis and a small number of other plants (like black pepper). 
• Terpenes are widely available and used in a range of household products in Australia, like perfumes, medicines, cosmetics and cleaning products.
• Some terpenes may interact with the endocannabinoid system (though not as strongly as cannabinoids), but more research is needed in this area⁶. 
• Terpenes can be psychoactive, but are unlikely to produce an intoxicating effect or ‘high’ on the user that is commonly associated with THC.

How do terpenes influence a patient’s experience of medicinal cannabis? 

Cannabis terpenes can affect a patient’s experience of medicinal cannabis in a number of ways – depending on the types, concentrations and combinations of terpenes in the flower, the cannabinoids and other compounds present, and the individual patient consuming the cannabis. 

Terpenes range dramatically in aroma, with varying smells often being associated with certain medicinal or psychoactive effects. These aromatic compounds are highly bioactive, and interact with different receptors in the body – including our endocannabinoid receptors – to produce varying effects.

Lavender, for example, which contains the terpene linalool (which is also found in many cannabis strains) is known for its calming effects. This means that linalool-rich strains of cannabis are likely to have a calming, pain-relieving effect greater than what would be achieved with isolated cannabinoids or a strain with a different terpene profile. The terpene limonene – found in the oils of citrus plants – is associated with bright, uplifting and energy-boosting effects. This means that a limonene-rich strain of cannabis would be more likely to elevate a patient’s mood beyond what cannabinoids are capable of achieving on their own. 

Mounting scientific evidence suggests that terpenes play a considerable role in not only modulating the intoxicating effects of THC, but also working in synergy with other cannabinoids to potentially increase their therapeutic value. A 2018 review of CBD treatments for epilepsy found that patients with epilepsy who took full-spectrum CBD extract – including cannabinoids and terpenes – experienced improved symptoms and fewer side effects than those who took CBD isolate, which contains only cannabinoids¹².

So, if a medical cannabis treatment is selected for a patient based on THC or cannabinoid content alone, then that patient is likely being robbed of the full therapeutic experience and potential of their cannabis treatment. Not only will they miss out on the rich and distinct scents and flavours of the cannabis strain, but they will also miss out on the range of additional medicinal benefits that can only be experienced through a strain’s specific terpene profile. 

Most commonly known cannabis terpenes

There are many different types of terpenes present in the oils of plants, each producing different smells and tastes as well as effects on the humans and animals who consume them. The cannabis plant alone contains more than 150 terpenes which each contribute to the plant’s therapeutic qualities and potential health benefits. 

Here are just some of the most commonly known terpenes that can be found in medicinal cannabis treatments and in other plants::

Caryophyllene 

• Found in: Black Pepper, Cloves, Cotton
• Aromas: Pepper, Wood, Spice, Herbal
• Potential uses: Pain relief, Anti-inflammatory, Anxiety, Depression + more

Limonene

• Found in: Lemon, Fruit Rinds, Juniper
• Aromas: Citrus, Lemon, Orange
• Potential uses: Digestion, Anti-bacterial, Stress relief

Farnesene

• Found in: Chamomile, Rose, Potatoes
• Aromas: Sandalwood, Floral, Wood
• Potential uses: Anti-inflammatory, Anti-allergy, Muscle relaxant

Humulene

• Found in: Sage, Ginseng, Hops
• Aromas: Earth, Wood, Spice
• Potential uses: Anti-inflammatory, Antibacterial, Appetite-suppressing

Myrcene

• Found in: Mango, Thyme, Lemongrass
• Aromas: Musk, Earth, Citrus
• Potential uses: Anti-inflammatory, Relaxing, Pain relief

Terpinolene

• Found in: Lilac, Sage, Rosemary
• Aromas: Floral, Herbal, Pine
• Potential uses: Antibacterial, Anxiety, Insomnia

Linalool

• Found in: Lavender, Coriander, Mint
• Aromas: Floral, Sweet, Woody
• Potential uses: Anxiety, Insomnia, Pain Relief

Pinene

• Found in: Pine needles, Rosemary, Basil
• Aromas: Fresh, Herbal, Earth
• Potential uses: Bronchodilator, Anti-inflammatory, Anxiety

Are terpenes good or bad for your patient?

Whether a terpene is good or bad for a patient depends on the plant it is found in and how it is being used. Terpenes themselves are legal and are not classed as a drug on any prohibited drug list. They exist in almost any plant (including herbs, fruits, vegetables and flowers) that you can find in your garden or at your local grocery store, such as lemons, rosemary and mangoes. They also exist in other plants, such as non-edible and toxic plants in the wild. 

In their pure, concentrated forms, terpenes can cause unwanted side effects like dizziness and irritation when consumed, inhaled or topically applied. This is why essential oils that have not been diluted should not be ingested or applied directly onto the skin¹³.

In diluted form (5% or less), terpenes are non-toxic and safe to use.

Are terpenes safe in cannabis?

Cannabis medicines are highly regulated in Australia for safety, cannabinoid and terpene content, quality and efficacy. Any terpenes found in these treatments have been deemed safe (and even beneficial!) for human consumption. Terpenes are not known to be addictive. 

Do all medicinal cannabis treatments contain terpenes?

Unfortunately, not all medicinal cannabis treatments contain terpenes. And for those treatments that do contain terpenes, not all suppliers measure terpene content from batch to batch, or place an emphasis on maintaining the plant’s terpene profile in production. This has the potential to lead to inconsistencies in the effects of those treatments from batch to batch. 

While medical cannabis products that use the full plant or whole flower contain the original terpene profiles of the plant, full-spectrum and broad-spectrum medical cannabis treatment (which also contain terpenes) may have reduced terpene profiles due to the extraction methods used to produce them. Isolates do not contain terpenes, however some isolate treatments may have a terpene or terpene blend added back in (that is not from the original plant) – these are known as terpsolates.

There are many variables that can affect the amount of terpenes found in cannabis strains. Environmental factors such as light exposure, temperature, whether the plant is grown outdoors or indoors, growth methods, nutrient levels, and harvest practices can all influence terpene levels. Because many terpenes are volatile compounds that easily evaporate, they are at risk of being lost during standard cannabis extraction processes. However thanks to more in-depth cannabis research and growing awareness of the therapeutic benefits of terpenes - and the potential health benefits of the 'entourage effect' - is leading to more sensitive extraction and production methods to help maintain the cannabis plant’s terpene profile.

Talking to your patients about terpenes 

Just like cannabinoids, you can help your patient choose an appropriate medicinal cannabis treatment based on its terpene profile and the effects these terpenes may have on the patient’s specific symptoms or condition. 

Terpenes may contribute to the overall effect of the cannabis cultivar  – i.e. whether it is sedative, calming, uplifting, or euphoric – or they might have individual medicinal benefits that are suited to your patient’s condition – such as being anti-inflammatory or a digestive aid. Also, terpenes affect the overall sensory experience of medical cannabis treatment, and there may be certain ones your patients prefer – just like if they were selecting a tea or coffee.

If your patients are looking to reap all of the health benefits that are native to the cannabis plant through their medicinal cannabis treatment, you might consider prescribing a treatment that incorporates a diverse terpene profile and an array of other compounds.