By Becky UphamNovember 2, 2022
People with fibromyalgia who wore special green eyeglasses for several hours a day had less anxiety and used fewer opioids to manage chronic pain than people who didn’t wear the glasses, according to a new study presented at Anesthesiology 2022 conference, held in San Francisco October 13–17.
“Our research found that certain wavelengths of green light stimulate the pathways in the brain that help manage pain,” said the lead author, Padma Gulur, MD, the executive vice chair of Duke Anesthesiology and Duke Health in Chapel Hill, North Carolina, in a press release. “There is an urgent need for additional treatments to reduce the use of opioids among patients with fibromyalgia and other types of chronic pain, and green eyeglasses could provide an easy-to-use, nondrug option,” she said.
4 Million U.S. Adults Have Fibromyalgia
It’s estimated that about four million adults in the United States are living with fibromyalgia, a chronic disease that causes pain and tenderness throughout the body, as well as fatigue and trouble sleeping, according to the Centers for Disease Control and Prevention (CDC). It’s not clear what causes the condition, but people living with it have a heightened sensitivity to pain.
People with fibromyalgia are more likely to have a lower quality of life, higher rates of depression, higher death rates from suicide and injuries, and higher rates of other rheumatic conditions such as osteoarthritis, lupus, rheumatoid arthritis (RA), and ankylosing spondylitis.
People Who Wore Green-Light Glasses Experienced Less Anxiety
The researchers studied 34 fibromyalgia patients who were randomized to wear various shades of eyeglasses for four hours a day for two weeks: 10 patients wore blue eyeglasses, 12 wore clear eyeglasses, and 12 wore green eyeglasses. Patients who wore green eyeglasses were four times more likely to have reduced anxiety than those in the other groups, who saw no reduction in anxiety.
Although the pain scores remained the same in both groups, those who wore the green eyeglasses used fewer opioids, demonstrating that their pain was adequately controlled, said Dr. Gulur.
Pain and anxiety are connected — they share similar biological mechanisms, said Gulur. Additionally, fear of pain exacerbates anxiety, often leading to increased opioid use, she said.
“We would recommend the green eyeglasses treatment for those with fibromyalgia, and we are studying patients with other chronic pain conditions to determine if it would be beneficial,” she said.
How Do Green-Light Glasses Work?
The eyeglasses are specially designed to filter a specific wavelength on the green light spectrum, said Gulur. “The likely mechanism of pain relief from green light starts with activation of photoreceptors in the eye that communicate with parts of the brain and modulate the pain response by activating the descending pain inhibitory pathways,” she said.
Green light may also affect the opioid receptor system and increase the level of enkephalins in the spinal cord, said Gulur. Enkephalins are peptides that occur naturally in the brain and are related to endorphins, with similar effects on the brain.
She noted that most patients who wore the green eyeglasses reported feeling better and asked to keep wearing them.
Are Green-Light Glasses Like the Ones Used in the Study Available?
Specific wavelengths of green light are necessary, and so green eyeglasses purchased off the shelf or online may not be helpful, said Gulur. “Custom glasses designed for those wavelengths are needed and are currently in development,” she said.