Cannabis terpenes have pain-relieving effects, study finds

New research from the US has found that terpenes mimic cannabinoids and produce similar pain-relieving effects.

Researchers, from the University of Arizona Health Sciences, have found that cannabis terpenes, when used by themselves, mimic the effects of cannabinoids, including a reduction in pain sensation. 

The study, by researchers favours the entourage effect theory, that the effects of the cannabis plant as a whole are greater than any of its individual parts. 

These findings position cannabis terpenes, the part of the plant that provides flavour and aroma, as a promising new target for pain therapies that would require lower doses and produce fewer side effects.

Terpenes are aromatic compounds found in many plants and are the basic component in essential oils. The terpene linalool, for example, gives lavender its distinctive floral scent. 

In addition to terpenes, cannabis contains naturally occurring compounds known as cannabinoids, the most well-known of which are cannabidiol, or CBD, and tetrahydrocannabinol, or THC, the psychoactive component of cannabis.

When combined with cannabinoids, the pain-relieving effects were amplified without an increase in negative side effects. 

Lead researcher John Streicher, PhD, a member of the UArizona Health Sciences Comprehensive Pain and Addiction Center,  said: “It was unexpected, in a way. It was our initial hypothesis, but we didn’t necessarily expect terpenes, these simple compounds that are found in multiple plants, to produce cannabinoid-like effects.”

Dr Streicher and his research team focused on four cannabis terpenes: alpha-humulene, geraniol, linalool and beta-pinene. 

They evaluated each terpene alone and in combination with WIN55,212-2, a synthetic cannabinoid agonist that stimulates the body’s natural cannabinoid receptors.

Behavioural studies in mouse models revealed that when administered individually, all four terpenes lowered pain sensitivity, and at least three of the four classic cannabinoid side effects: reduced pain sensation, lowered body temperature, reduced movement and catalepsy, a freezing behaviour related to the psychoactive effects of cannabinoids. 

When terpenes were combined with WIN55,212-2, researchers saw a greater reduction in pain sensation compared with either the terpene or WIN55,212-2 alone, demonstrating a terpene/cannabinoid interaction in controlling pain. 

Dr. Streicher’s ongoing research is focusing on the use of terpenes in combination with opioids and for specific types of cancer-related pain. 

The paper, Cannabis sativa terpenes are cannabimimetic and selectively enhance cannabinoid activity, was published in Scientific Reports.