Green Light Therapy for Chronic Pain

Overseen By Virginia Ellis

Age: 18+

Sex: Any

Trial Phase: Academic

Sponsor: University of Arizona

Disqualifiers: Serious mental illness, Color blindness, others

Compensation: Varies

Number of Visits: 5

Duration: 10 weeks

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial aims to explore how green light therapy can reduce pain in people with fibromyalgia, a condition known for causing widespread pain and fatigue. Researchers believe green light might reduce inflammation in the brain, altering how pain signals are processed. Participants will be exposed to either green light or a placebo (inactive treatment) using white light for two hours daily over ten weeks. This study may suit those with fibromyalgia who experience significant daily pain and find standard medical treatments insufficient. As an unphased trial, this study offers a unique opportunity to contribute to innovative research that could lead to new treatment options.

Will I have to stop taking my current medications?

The trial protocol does not specify whether you need to stop taking your current medications. However, since the trial is for those whose medical therapy has failed to control their pain, it might be possible to continue your current medications. Please confirm with the trial coordinators.

What prior data suggests that green light therapy is safe for humans?

Research has shown that green light therapy (GLED) can reduce pain in both people and animals. In earlier studies with animals, GLED relieved pain without causing side effects or affecting movement. For people with fibromyalgia and migraines, GLED resulted in less pain and fewer headaches.

These studies have found no safety issues, indicating that GLED is generally safe. While scientists continue to explore how GLED eases pain, current evidence supports its safety and potential benefits for managing pain. ^{1 2 3 4 5}

Why are researchers excited about this trial?

Unlike traditional treatments for chronic pain, which often rely on medications like opioids or nonsteroidal anti-inflammatory drugs (NSAIDs), green light therapy offers a non-invasive alternative. Researchers are excited about this treatment because it uses green light-emitting diodes (GLED) to potentially alleviate pain without the side effects associated with pharmaceuticals. The mechanism involves exposing patients to green light for specific periods, which is thought to alter pain perception by influencing brain pathways. This novel approach could provide a safer and more sustainable option for managing chronic pain.

What evidence suggests that Green Light Therapy is effective for chronic pain?

Research shows that green light therapy can help manage chronic pain. In earlier studies, individuals with fibromyalgia experienced significantly less pain when exposed to green light, reporting a 60% decrease in pain levels, from an 8 to a 3.2 on a scale of 0 to 10. Additionally, green light has been found to boost the body's natural painkillers, reducing pain and swelling. This trial will compare the effects of green light-emitting diode (GLED) therapy, which participants may receive, with a placebo comparator using white light-emitting diode (WLED) therapy. While scientists are still determining the exact mechanism, these results suggest that green light therapy could be a promising way to relieve pain. ^{1 2 3 6 7}

Who Is on the Research Team?

Mohab M Ibrahim, PhD., MD

Principal Investigator

University of Arizona

Are You a Good Fit for This Trial?

This trial is for adults over 18 who speak English, have been diagnosed with fibromyalgia according to specific criteria, and experience chronic pain rated at least 5 out of 10 despite medical treatment. People with serious mental illness, color blindness, uncorrected cataracts or those paid for their condition are excluded.

Inclusion Criteria

My average pain level is 5 or more out of 10, and treatments haven't helped.

My average pain level is 5 or more out of 10, and medications haven't helped.

I have been diagnosed with fibromyalgia according to the latest criteria.

Exclusion Criteria

You are getting paid for your medical condition.

You have a history of color blindness or have not had your cataracts corrected.

You have a serious mental illness that causes you to have trouble telling what's real and what's not, or may lead to unusual behaviors.

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

1-2 days

1 visit (in-person)

Baseline Assessment

Collection of baseline Fibromyalgia Impact Questionnaire survey, thermal and mechanical pain detection and tolerance threshold, conditioned pain modulation, cerebrospinal fluid, and PET scan for microglia baseline activity

1-2 days

1 visit (in-person)

Treatment

Participants receive either GLED or WLED exposure for 2 hours a day over 10 weeks

10 weeks

Follow-up calls every 2 weeks

Follow-up

Final assessment of Fibromyalgia Impact Questionnaire survey, thermal and mechanical pain detection and tolerance threshold, conditioned pain modulation, cerebrospinal fluid, and PET scan

1-2 days

1 visit (in-person)

What Are the Treatments Tested in This Trial?

Interventions

• Green Light

Trial Overview

The study tests Green Light Therapy (GLED) as a potential treatment for fibromyalgia and chronic pain. It aims to understand how GLED might reduce pain by affecting the brain's processing of pain signals. Participants will be randomly assigned to receive either GLED or a placebo in a controlled environment.

How Is the Trial Designed?

Group I: Green light-emitting diode (GLED) Experimental Treatment 1 Intervention

Subjects randomized to this arm will be exposed to GLED 2 hours a day for 10 weeks

Group II: White light-emitting diode (WLED) Placebo Group 1 Intervention

Subjects randomized to this arm will be exposed to WLED 2 hours a day for 10 weeks

Who Is Running the Clinical Trial?

University of Arizona

Lead Sponsor

Trials

545

Recruited

161,000+

Banner Alzheimer's Institute

Collaborator

Trials

9

Recruited

3,000+

Published Research Related to This Trial

Phototherapy, particularly using red light (660 nm), can effectively reduce pain in conditions like neuropathies and complex regional pain syndrome-I, but visual exposure to the same wavelength may worsen migraines.

Green light exposure has been shown to alleviate pain in various conditions, including migraines and fibromyalgia, highlighting the importance of light color and exposure method in pain management.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Mechanisms and Pathways of Pain Photobiomodulation: A Narrative Review. Cheng, K., Martin, LF., Slepian, MJ., et al.[2023]

In a clinical trial involving 43 participants, low-level laser therapy using green and violet wavelengths significantly reduced chronic musculoskeletal pain, with visual analog pain scores dropping from 71.79 to 34.02 just three minutes after treatment (p < 0.0001).

A remarkable 81.4% of participants experienced a reduction of 30% or more in their pain scores, supporting the efficacy of this therapy and leading to the first FDA clearance for the combined use of these laser wavelengths.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Assessing the Impact of High Photon Energy Wavelengths on the Treatment of Chronic Neck and Shoulder Pain. Sammons, T., Gair, K., Silverman, RG., et al.[2023]

Green light therapy has been shown to effectively reduce postsurgical pain in rats, suggesting its potential as a non-pharmacological pain management option that could minimize opioid use.

The therapy enhances the pain-relieving effects of morphine and ibuprofen, particularly increasing endogenous opioid levels and reducing neuroinflammation, which could lead to improved pain control in clinical settings.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Green Light Exposure Elicits Anti-inflammation, Endogenous Opioid Release and Dampens Synaptic Potentiation to Relieve Post-surgical Pain. Martin, LF., Cheng, K., Washington, SM., et al.[2023]

Citations

1.

pmc.ncbi.nlm.nih.gov

pmc.ncbi.nlm.nih.gov/articles/PMC7861466/

Green Light Exposure Improves Pain and Quality of Life in ...

(B) GLED exposure produced greater and statistically significant improvement in the quality of life and the patients' perception of their own ...

2.

medschool.duke.edu

medschool.duke.edu/stories/pain-management-gets-green-light

Pain Management Gets the Green Light

Larger studies that assess green light exposure on different chronic pain conditions are in store. There's also interest in the dose effect, ...

3.

sciencedirect.com

sciencedirect.com/science/article/pii/S1526590022004370

Green Light Exposure Elicits Anti-inflammation ...

We showed that green light increases endogenous opioid levels while lessening synaptic plasticity and neuroinflammation.

4.

annualreports.healthsciences.arizona.edu

annualreports.healthsciences.arizona.edu/2023/story/cpac-green-light-therapy/

Shining a green light on pain relief - Annual Reports

Using a numeric pain scale of 0 to 10, participants noted that green light exposure resulted in a 60% reduction in pain, from 8 to 3.2. Green light therapy also ...

5.

clinicaltrials.gov

clinicaltrials.gov/study/NCT03677206

NCT03677206 | The Effect of Light Therapy on Chronic Pain

Several clinical trials have shown that certain wavelengths of light can improve wound healing, decrease temporomandibular joint dysfunction (TMJ) pain, and ...

6.

journals.lww.com

journals.lww.com/pain/fulltext/2025/06000/visual_exposure_to_green_light_therapy_reduces.8.aspx

Visual exposure to green light therapy reduces knee joint...

Visual exposure to dim, green, light has been found to reduce pain levels in patients living with migraine, low back pain, and fibromyalgia.

7.

pharmacology.arizona.edu

pharmacology.arizona.edu/green-light-exposure-elicits-anti-inflammation-endogenous-opioid-release-and-dampens-synaptic

Green Light Exposure Elicits Anti-inflammation, Endogenous ...

Green light therapy has been shown to be effective in reducing chronic pain in humans and rodents. However, its underlying mechanisms remain incompletely ...