Ensemble Benefits of Terpenes for Anxiety & Depression

Depression affects millions of people globally. Coupled with anxiety disorders, the two are the most prevalent mental conditions. Unfortunately, the pharmaceutical drugs used to treat these conditions often cause severe side effects and addiction in some cases. [1]

A review published in Current Neuropharmacology in 2020 has drawn out some key observations on the potential ensemble benefits offered by terpenes for treating psychiatric disorders. [2] Below is a glimpse of the findings.

The endocannabinoid system (ECS) has been largely implicated in mood regulation and consequently in the treatment of depression, anxiety, and bi-polar disorders.

The two most studied phytocannabinoids are Δ⁹-tetrahydrocannabinol (THC) and cannabidiol (CBD). So far, it’s been demonstrated that these compounds interact with the ECS via cannabinoid receptors in different ways through different mechanisms.

CBD has shown higher effectiveness in relieving mood disorders such as anxiety [3] and depression, routinely demonstrating antidepressant and anti-anxiety effects in animal models. [4,5] In mouse models, THC has shown mild antidepressant-like effects which are more prominent on males more than on females. [6] In humans, combined THC and CBD exhibit anti-depressant and anti-stress effects. [7]

What About Terpenes?

Preliminary studies on terpenes have shown potential in treating psychiatric conditions. [8] One study showed anti-anxiety effects produced by terpenes present in propolis essential oil. [9] A systemic review of anti-anxiety effects of essential oils also showed similar positive results. [10]

One essential oil, Lavendula angustifolia (English Lavender), has shown such effects in controlled clinical trials. [11] Other essential oils with similar effects in clinical trials include Citrus synesis (sweet orange) [12] and bergamot oil [13]. Further research is needed to investigate the potential antidepressant activity of these essential oils and their terpenes.

Mode of Action

Research has shown that most essential oils exert anti-anxiety effects in a way that’s different from benzodiazepines. For example, the effects of D-limonene are not blocked by flumazenil, which is a benzodiazepine inhibitor. [14] This provides hope for a treatment option with reduced risk for addiction.

A different study showed that linalool and β-pinene exhibit antidepressant-like effects by interacting with the monoaminergic system. [15] Consequently, caution needs to be exercised when administering monoaminergic antidepressants concurrently with terpenes.

Entourage/Ensemble Effects

In cannabis, entourage or ensemble effects refer to enhanced positive effects that are produced when terpenes are combined with cannabinoids (or when multiple cannabinoids or multiple terpenes potentiate each other). [16] It can be described beautifully in the common phrase “the whole is greater than the sum of parts.” It has also been described as “botanical synergy.”

The researchers concluded that further research is needed to paint a clearer picture on the role of entourage benefits offered by terpenes in the treatment of anxiety and depression. For now, we remain cautiously optimistic that this could provide a safe option with few side effects and low risk for addiction as compared to conventional treatments for psychiatric disorders. [2]

Image source

MariaHuxley from Pixabay 

References

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