Understanding Terpenes in Cannabis: The Role of Myrcene

Myrcene is one of the most common aromatic compounds (terpenes) found in medicinal cannabis. It is often associated with “relaxing” or “night-time” products, but the science is more nuanced than social media would suggest. This article gives a clinically balanced, patient-friendly overview of what we know (and don’t know) about myrcene. It is general information only and does not replace individual medical advice.

Key takeaways

• Myrcene is one of the most common terpenes in cannabis and also occurs in plants such as hops, lemongrass and mango.[1]

• Preclinical studies suggest myrcene has anti-inflammatory, analgesic and sedative-like properties, and may contribute to the “heavier” or more relaxing feel of some cannabis products.[1,2,5–7,10]

• The idea that myrcene alone explains couch-lock is an oversimplification. Effects in humans depend on the full cannabinoid and terpene profile, dose, route of administration and patient factors.[3,4]

• Regulatory safety assessments of myrcene have mainly focused on high-dose synthetic use as a flavouring agent in food. These do not directly translate to typical exposures from medicinal cannabis, but they remind us that dose matters.[8,9]

• At present, robust human data are limited. Myrcene should be viewed as one component of a whole-plant medicine, not a magic bullet. Clinician guidance and careful monitoring remain essential.[1,3,4]

What are terpenes?

Terpenes are aromatic oils produced by many plants, including cannabis, citrus, pine, lavender and hops. They help give a product its scent and flavour, and in cannabis they may also influence how a product feels.

In cannabis, terpenes sit alongside cannabinoids such as THC and CBD. Together, these compounds may contribute to the so-called “entourage effect” – the idea that cannabinoids, terpenes and other plant chemicals work together to shape the overall effect rather than acting in isolation.[3,4]

If you’d like a broader overview of terpenes and how temperature affects them, see our article on terpenes in medicinal cannabis and vaporiser temperature, and our step-by-step guide to using a dry herb vaporiser.

For cannabinoid basics, see our primer on cannabinoids (THC, CBD, CBC, CBG and CBN).

What is myrcene?

Myrcene (β-myrcene) is a monoterpene found in cannabis, hops, lemongrass, thyme and mango.[1]

In cannabis lab reports, myrcene is frequently one of the dominant terpenes. It is typically described as having:

• Aroma: earthy, musky, herbal; sometimes slightly fruity

• Common associations: “chill”, body-heavy or night-time products

Outside cannabis, myrcene has been used for many years as a flavouring and fragrance ingredient in foods, drinks and cosmetics.[1,8,9]

If you’re interested in how myrcene compares to another key terpene, you may like our deep dive on caryophyllene.

Why is myrcene linked to “sedation” and couch-lock?

Many patients notice that some terpene profiles feel “heavier” or more relaxing than others. Myrcene is often blamed (or credited) for the classic “couch-lock” feeling.

In preclinical research:

• Rodent studies suggest that myrcene can have sedative and muscle-relaxant effects at higher doses, and can lengthen barbiturate-induced sleep time.[5,6]

• Recent work in insomnia mouse models also suggests sedative-hypnotic activity of β-myrcene within essential-oil preparations.[7]

These findings support the idea that myrcene might contribute to more relaxing effects when present in higher amounts. However, several important caveats apply:

• These are animal studies, often using doses much higher (per kg body weight) than typical human exposure from cannabis or food.

• Human data linking specific myrcene levels to sedation are limited and mostly observational.

• The overall effect you feel is driven by multiple factors: THC and CBD dose, other terpenes, route of administration, your prior exposure, mental state, sleep, other medications and underlying health.[3,4,10]

In other words: myrcene may be one contributor to a “heavier” or more relaxing profile, but it is not the only variable. The idea that eating a mango (which contains myrcene) will dramatically increase your “high” remains a myth rather than an evidence-based recommendation.[1,3]

For a broader discussion of these ideas, see our article on THC strength and the entourage effect.

What does the research suggest so far?

Most of the research on myrcene comes from laboratory and animal studies. The main themes are:

1. Pain and inflammation

• Myrcene can reduce responses to painful thermal and mechanical stimuli in rodent models.[2]

• In a rat model of chronic arthritis (adjuvant monoarthritis), topical myrcene reduced joint inflammation and pain behaviours.[2]

• Reviews of terpenes in pain suggest that myrcene’s analgesic effects may relate to both anti-inflammatory and neuromodulatory actions.[1,10]

2. Sedative-like and anxiolytic-like actions (preclinical)

• Myrcene has shown sedative and motor-relaxant effects in rodent behavioural tests.[5,6]

• Experimental work in mice models of insomnia suggests myrcene-containing preparations may influence neurotransmitters such as GABA and serotonin, consistent with calming or sleep-supportive effects.[7]

3. Possible synergy with cannabinoids

• A widely cited pharmacology review proposed that myrcene might enhance some effects of THC and contribute to the “entourage effect”.[3]

• A more recent review of the entourage effect in cannabis medicines concludes that terpenes such as myrcene may have therapeutic potential and could modify cannabinoid effects, but that robust human data are still limited and results are mixed.[4]

4. Human evidence

• At present, there are no large, high-quality clinical trials where myrcene concentration is systematically varied while other factors are tightly controlled.

• Most human observations come from real-world use of whole-plant cannabis products, where many variables change together.

In practice, clinicians tend to treat myrcene as one part of the broader terpene and cannabinoid profile, rather than as a stand-alone “sleep ingredient”.

Safety and side effects

General toxicology and regulatory assessments

Myrcene has been evaluated by multiple food-safety and regulatory bodies, mainly in the context of its use as a flavouring and fragrance ingredient rather than as a medicine.[1,8,9]

Key points:

• Historical food-use data and toxicology work supported its previous classification as “generally recognised as safe” (GRAS) when used at low levels as a flavouring agent.

• Later high-dose rodent studies identified tumour findings when myrcene was administered at doses far exceeding typical human dietary or fragrance exposure. Under the strict “Delaney Clause” in US law (which prohibits listing any additive with evidence of carcinogenicity in animals), the FDA removed synthetic myrcene from the permitted food-additive list, despite actual human risk at normal exposures being considered low.[9]

• European assessments (for example, EFSA) have considered myrcene as part of broader groups of flavouring substances and have used standard toxicology approaches (NOAELs, margins of safety) to set acceptable exposure limits for food use.[8]

These decisions relate to added synthetic myrcene in food, not to naturally occurring myrcene in plants such as cannabis or hops. Nonetheless, they remind us that “natural” does not always mean risk-free, and that dose and route of administration matter.

Practical considerations for patients

When myrcene is present as part of a cannabis product:

• Side effects are usually dominated by THC (for example, dizziness, dry mouth, anxiety, impaired driving) rather than by myrcene itself.

• Myrcene-rich products might feel subjectively more sedating or “body-heavy” for some people; this may be desirable at night but unhelpful if you need to remain alert.

• Theoretical interactions with other sedatives (e.g. benzodiazepines, opioids, alcohol) are a consideration, even though direct human data are limited. Caution and medical supervision are advised.

• As with any inhaled or vapourised product, there is a risk of airway irritation. Patients with asthma or chronic lung disease should discuss this carefully with their treating doctor.

If you are pregnant, breastfeeding, have a history of psychosis, problematic substance use, or complex medical comorbidities, specialist medical advice is essential before considering medicinal cannabis of any kind.

How might this information affect product choice?

For many patients, exact terpene percentages will be less important than getting the fundamentals right: clear indication, realistic goals, careful dosing and follow-up. When terpenes are available on the lab report, they can still be a helpful extra layer of information.

Points to consider and discuss with your doctor:

• Look beyond THC percentage. Ask about both cannabinoid and terpene profiles. A product with moderate THC plus supportive terpenes may be more suitable than a very high-THC product for some indications.[3,4,10]

• Match timing to effect. If myrcene-rich products feel heavier or more sedating for you, they may be better suited to evening or night-time use rather than daytime tasks or driving.

• Route matters. Vapourising dried flower with a temperature-controlled dry-herb vaporiser will give a different onset and duration than oils or capsules. Temperature also affects terpene delivery. You can read more in our article on terpenes and vaporiser temperature and our guide to using a dry herb vaporiser.

• Track your own response. Keeping a simple log (product, dose, time, mode of administration, aroma, perceived effects and side effects) can be very helpful for you and your prescriber.

For an overview of cannabinoids themselves, see our primer on cannabinoids (THC, CBD, CBC, CBG and CBN).

Pricing, access and next steps

Access and cost are major considerations in Australia. If you are considering medicinal cannabis:

• You can find more information about getting started in our guide to medicinal cannabis online.

• For an overview of pricing and ways to keep treatment affordable, see our guide to cheap medical cannabis.

• Common practical questions are covered in our FAQ page.

If you feel ready to speak with a doctor experienced in medicinal cannabis, you can book an initial consultation using our online booking calendar for medical cannabis initial consults.

References

1. Surendran S, Qassadi F, Lilley D, et al. Myrcene—What Are the Potential Health Benefits of This Flavouring Agent? Frontiers in Nutrition. 2021;8:699666.

2. McDougall JJ, et al. Anti-Inflammatory and Analgesic Properties of the Cannabis Terpene Myrcene in Rat Adjuvant Monoarthritis. Pain. 2022.

3. Russo EB. Taming THC: Potential Cannabis Synergy and Phytocannabinoid–Terpenoid Entourage Effects. British Journal of Pharmacology. 2011;163(7):1344–1364.

4. André R, et al. The Entourage Effect in Cannabis Medicinal Products: From Molecular Mechanisms to Clinical Evidence. Pharmaceuticals. 2024.

5. do Vale TG, Furtado EC, Santos JG Jr, Viana GS. Central Effects of Citral, Myrcene and Limonene, Constituents of Essential Oils. Pharmacology Biochemistry and Behavior. 2002;71(1–2):31–36.

6. Szaszkiewicz J, et al. Robust Behavioural Effects in Response to Acute, but Not Chronic, Inhalation of the Cannabis Terpene β-Myrcene in Mice. Scientific Reports. 2021;11.

7. Chen L, et al. Beta-Myrcene as a Sedative–Hypnotic Component from Lavender Essential Oil in Insomnia Mice. Journal of Ethnopharmacology. 2024.

8. EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (CEF). Flavouring Group Evaluation 18, Revision 3 (FGE.18Rev3): Aliphatic and Alicyclic Hydrocarbons Including Myrcene. EFSA Journal. 2015;13(10):4118.

9. Mog SR, Zang YJ. Safety Assessment of Food Additives: Case Example With Myrcene, a Synthetic Flavoring Agent. Toxicologic Pathology. 2019;47(8):1035–1037.

10. Liktor-Busa E, et al. Analgesic Potential of Terpenes Derived from Cannabis sativa. Pharmacology. 2021.