Cannabis Terpenes Studied for Pain Relief
Researchers at the University of Arizona Health Sciences report that four compounds found in Cannabis sativa may reduce pain in preclinical models of fibromyalgia and post-surgical pain. The study, published in Pharmacological Reports, examined terpenes, aromatic plant chemicals that do not produce the psychoactive effects associated with THC.
The team, led by professor John Streicher, tested geraniol, linalool, beta-caryophyllene and alpha-humulene. All four were associated with reduced pain-related behaviors in models of fibromyalgia and pain after surgery. Geraniol showed the strongest effect, followed by linalool, beta-caryophyllene and alpha-humulene. Earlier work from the same laboratory found that terpenes reduced pain in models of inflammation and chemotherapy-related nerve damage, but were less useful for immediate injury-related pain.
Fibromyalgia affects muscles and soft tissues and is difficult to treat, because its underlying mechanisms remain unclear. Estimates cited by researchers suggest it affects up to 5% globally and about 4 million U.S. adults, with women diagnosed more often than men. Streicher said the findings indicate terpenes could become a treatment option, while noting the work remains preclinical.
The study considered post-operative pain, which is temporary but can involve inflammation and increased sensitivity in pain pathways. Opioids are commonly used after surgery, but researchers noted that side effects, including constipation, can complicate recovery. With hundreds of millions of major surgeries performed worldwide each year, the authors said additional pain-management approaches are needed.
The researchers reported that the terpenes appeared to act through the adenosine A2a receptor, a biological target affected by caffeine. Because this pathway may be linked to sedation, they said further studies are needed to assess benefits, risks, dosing and whether results in mice translate to people.
The NIH funded the research, which university officials said reflects broader interest in natural products as possible sources of medicines.