Green Light Therapy for Chronic Pain

Overseen By Laurent F Martin, PhD

Age: 18 - 65

Sex: Any

Trial Phase: Academic

Sponsor: University of Arizona

Disqualifiers: Serious mental illness, Colorblindness, Tissue damage, others

Compensation: Varies

Number of Visits: 2

Duration: 1 day

30 Participants Needed

Trial Summary

Do I need to stop my current medications for the trial?

The trial information does not specify whether you need to stop taking your current medications.

What data supports the effectiveness of the treatment Green Light Emitting Diode for chronic pain?

Research shows that green light therapy can reduce pain in various conditions. In a study with rats, green light exposure increased pain tolerance and reduced pain without side effects. Additionally, a clinical trial found that green light improved pain and quality of life in fibromyalgia patients. ^{1 2 3 4 5}

Is green light therapy safe for humans?

Research indicates that green light therapy, using green light-emitting diodes (GLED), is considered safe for humans. Studies on conditions like migraines and fibromyalgia have noted the safety of GLED, and its ease of use has been highlighted in clinical trials. ^{2 3 6 7 8}

How does green light therapy differ from other treatments for chronic pain?

Green light therapy is unique because it is a non-drug treatment that uses green light-emitting diodes (LEDs) to manage pain, potentially through the visual system and central opioid circuits, without the side effects associated with medications. It offers a novel approach by increasing enkephalins (natural pain-relieving chemicals) in the spinal cord and altering calcium channel activity, providing long-lasting pain relief without developing tolerance. ^{1 3 6 9 10}

What is the purpose of this trial?

This research project is intended to understand the mechanisms of action for the pain-relieving properties of visual green light exposure. The investigators have shown previously that greenlight exposure decreased acute and chronic pain in both animals and humans. However, the investigators do not yet understand how green light exposure is capable of such function.

Research Team

Mohab Ibrahim, PhD, MD.

Principal Investigator

University of Arizona

Eligibility Criteria

This trial is for English-speaking men and women aged 18-50 who are generally healthy, without chronic pain or neuropathies in certain body areas. It's not suitable for those with colorblindness, uncorrected cataracts, serious mental illness, or tissue damage where testing will occur.

Inclusion Criteria

I do not have a history of chronic pain.

I am a healthy adult between 18 and 50 years old.

Able to speak and understand English

Exclusion Criteria

You have trouble seeing colors or have not had surgery for cataracts.

I do not have tissue damage in my forearms, hands, or upper back.

You have severe mental illness that causes you to have trouble telling what's real and what's not.

Timeline

Screening

Participants are screened for eligibility to participate in the trial

1-2 weeks

Baseline Assessment

Participants undergo baseline testing of pain pathways and brain wave activities using thermal and mechanical stimulations and EEG

1 day

1 visit (in-person)

Treatment

Participants are exposed to green or white light for two hours, followed by post-exposure testing of pain pathways and EEG

1 day

1 visit (in-person)

Follow-up

Participants are monitored for any delayed effects of light exposure on pain perception and brain activity

1-2 weeks

Treatment Details

Interventions

• Green Light Emitting Diode

Trial Overview The study aims to understand how green light exposure can relieve pain by comparing the effects of green and white light-emitting diodes (LEDs) on participants. The mechanisms behind the pain-relieving properties observed in previous studies are being investigated.

Participant Groups

Group I: Green Light Exposure Active Control 1 Intervention

Subjects will complete thermal and mechanical pain threshold detection tests and Electroencephalography (EEG). After completion, subjects will be exposed to a green light-emitting diode for two hours. After exposure, thermal and mechanical pain threshold assessments and Electroencephalography (EEG) will be conducted.

Group II: White Light Exposure Placebo Group 1 Intervention

Subjects will complete thermal and mechanical pain threshold detection tests and Electroencephalography (EEG). After completion, subjects will be exposed to a white light-emitting diode for two hours. After exposure, thermal and mechanical pain threshold assessments and Electroencephalography (EEG) will be conducted.

Who Is Running the Clinical Trial?

University of Arizona

Lead Sponsor

Trials

545

Recruited

161,000+

Findings from Research

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]

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]

References

1. United States pubmed.ncbi.nlm.nih.gov

Long-lasting antinociceptive effects of green light in acute and chronic pain in rats. [2021]

2. United States pubmed.ncbi.nlm.nih.gov

Assessing the Impact of High Photon Energy Wavelengths on the Treatment of Chronic Neck and Shoulder Pain. [2023]

3. England pubmed.ncbi.nlm.nih.gov

Green Light Exposure Improves Pain and Quality of Life in Fibromyalgia Patients: A Preliminary One-Way Crossover Clinical Trial. [2022]

4. United States pubmed.ncbi.nlm.nih.gov

Improvement of pain and disability in elderly patients with degenerative osteoarthritis of the knee treated with narrow-band light therapy. [2019]

5. United States pubmed.ncbi.nlm.nih.gov

Mechanisms and Pathways of Pain Photobiomodulation: A Narrative Review. [2023]

6. England pubmed.ncbi.nlm.nih.gov

Evaluation of green light exposure on headache frequency and quality of life in migraine patients: A preliminary one-way cross-over clinical trial. [2022]

7. England pubmed.ncbi.nlm.nih.gov

Evidence of changes in sural nerve conduction mediated by light emitting diode irradiation. [2018]

8. England pubmed.ncbi.nlm.nih.gov

Evaluation of the therapeutic effects of led (λ627 ± 10 nm) on the initial phase of ankle sprain treatment: a randomised placebo-controlled clinical trial. [2018]

9. United States pubmed.ncbi.nlm.nih.gov

Light-Emitting Diode Phototherapy Reduces Nocifensive Behavior Induced by Thermal and Chemical Noxious Stimuli in Mice: Evidence for the Involvement of Capsaicin-Sensitive Central Afferent Fibers. [2022]

10. Switzerland pubmed.ncbi.nlm.nih.gov

Flexible and Lightweight Devices for Wireless Multi-Color Optogenetic Experiments Controllable via Commercial Cell Phones. [2022]