Light Therapy for Chronic Pain

Overseen By Matthew C Mauck, MD, PhD

Age: 18+

Sex: Any

Trial Phase: Academic

Sponsor: University of North Carolina, Chapel Hill

Disqualifiers: Vision disorders, Color blindness, Pregnancy, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Compensation: Varies

Number of Visits: 5

Duration: 1 week

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial explores whether different types of light can reduce chronic pain, such as that experienced with fibromyalgia or chronic low back pain. Researchers aim to determine if specific light stimuli can lessen pain severity and sensitivity. Participants will use a light device for short daily sessions to test three different light types: Equal Energy White stimulation, Green Light stimulation, and S-cone modulating white light. This trial suits individuals diagnosed with fibromyalgia or chronic low back pain who experience significant daily pain and can commit to wearing the light device for 2 hours each morning. As an unphased trial, it offers a unique opportunity to explore innovative pain management solutions.

Will I have to stop taking my current medications?

The trial information does not specify whether you need to stop taking your current medications. It might be best to discuss this with the study team or your doctor.

Is there any evidence suggesting that this trial's treatments are likely to be safe?

Research shows that light therapy is generally safe and well-tolerated for managing chronic pain. Studies on similar light treatments have not identified any significant harmful effects. For instance, green light therapy, which is drug-free, is recognized for its safety and does not cause issues like tolerance or drowsiness, common with medications.

Other studies have examined light for pain relief and found it effective without major side effects. In animal studies, green light exposure did not produce noticeable negative effects, suggesting it might be safe for humans as well.

The specific therapies being tested, such as Equal Energy White stimulation, Green Light stimulation, and S-cone modulating white light, involve light exposure to the eyes. These non-invasive therapies use only light and are expected to be safe for people.

However, it is important to remember that these treatments are still under study. While early results are promising, ongoing research will continue to assess their safety and effectiveness. Participants should always discuss potential risks with trial organizers and healthcare providers. ^{1 2 3 4 5}

Why are researchers excited about this trial?

Researchers are excited about these light therapies for chronic pain because they offer a non-invasive, drug-free alternative to traditional treatments like medications or physical therapy. Unlike standard pain relief methods, these therapies use specific light wavelengths to potentially influence how our bodies perceive pain. The Equal Energy White stimulus provides balanced light to minimize color perception, the Green Light stimulus focuses on a specific light wavelength known for calming effects, and the S-cone modulating light targets specific eye receptors for a unique approach to pain modulation. These treatments could offer faster relief with fewer side effects, providing a promising new way to tackle chronic pain.

What evidence suggests that this trial's light therapies could be effective for chronic pain?

Research shows that light therapy might help reduce chronic pain. This trial will explore different types of light therapy, including green light and white light. Studies have found that green light, one of the treatments in this trial, can lower pain levels in conditions like migraines, low back pain, and fibromyalgia. In one study, green light reduced migraine pain by about 20%. Another treatment in this trial, white light, activates all three types of light-sensitive cells in the eye evenly and might also help reduce pain sensitivity. Although limited data exists on a specific type of white light affecting certain cells, early results suggest that different light colors might help manage pain. Overall, promising evidence indicates that light therapy could effectively relieve chronic pain. ^{1 4 5 6 7}

Who Is on the Research Team?

Matthew C Mauck, MD PhD

Principal Investigator

University of North Carolina, Chapel Hill

Are You a Good Fit for This Trial?

Adults over 18 with fibromyalgia or chronic low back pain, who rate their pain at least 7/10, can join this trial. They must be willing to use a light therapy device for two hours each morning for five days and be able to read and speak English. People with seizure disorders, severe vision impairments, color blindness, pregnancy, or prisoners cannot participate.

Inclusion Criteria

My average pain level is more than 7 out of 10.

I have been diagnosed with fibromyalgia or chronic low back pain.

I am willing to use a light therapy device for 2 hours daily in the morning.

Exclusion Criteria

Pregnancy

I am mentally capable of understanding and agreeing to the trial.

Prisoner Status

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

1-2 weeks

Treatment

Participants receive light stimuli via a portable battery-operated ganzfeld light stimulation device for 2 hours per day for 5 consecutive days

1 week

5 visits (in-person)

Follow-up

Participants are monitored for changes in pain intensity and activity levels after treatment

1 week

What Are the Treatments Tested in This Trial?

Interventions

• Equal Energy White stimulation
• Green Light stimulation
• S-cone modulating white light

Trial Overview The study tests if different types of light stimuli (Green Light stimulation, Equal Energy White stimulation, S-cone modulating white light) presented through a portable device can reduce chronic pain severity and sensitivity in patients with conditions like fibromyalgia and lower back pain.

How Is the Trial Designed?

Group I: S-cone modulating white light Experimental Treatment 1 Intervention

The S-cone modulating light stimulus will alternate between two light conditions at 500 lux that will activate the S-cones by about 100x differentially between the two conditions while maintaining the L- an M-cones at constant activation between the two alternating conditions using 427 nm versus 545 nm light. The stimulus will be delivered by a portable battery-operated ganzfeld light stimulation device for 2 hours per day for 5 consecutive days.

Group II: Green light stimulus Experimental Treatment 1 Intervention

Green light at 500 lux. Participants will view 545 nm green light delivered via a portable battery-operated ganzfeld light stimulation device for 2 hours per day for 5 consecutive days.

Group III: Equal energy white stimulus Experimental Treatment 1 Intervention

Equal energy white light at 500 lux. The International Commission on Illumination (CIE) coordinates of this light are (x=y=0.33), indicating that the stimulus appears uniformly white which means that the activation of each of the three classes of photoreceptors are equivalent, thus silencing any chromatic opponency. The stimulus will be delivered by a portable battery-operated ganzfeld light stimulation device for 2 hours per day for 5 consecutive days.

Who Is Running the Clinical Trial?

University of North Carolina, Chapel Hill

Lead Sponsor

Trials

1,588

Recruited

4,364,000+

Published Research Related to This Trial

Bright light therapy is effective for treating seasonal affective disorder (SAD) and has potential applications for other conditions like circadian sleep phase disorders and jet lag, but the safety of different light sources is a concern.

The study analyzed various light therapy fixtures, revealing that many emit unknown spectral emissions that could cause ocular damage, leading to recommendations for safer lamp choices and monitoring for patients undergoing prolonged treatment.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Bright light therapy in focus: lamp emission spectra and ocular safety. Remé, CE., Rol, P., Grothmann, K., et al.[2007]

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]

In a study of 200 chronic pain patients, the color of the paper used for the Numerical Rating Scale (NRS) questionnaire did not affect overall pain scores, indicating that visual stimulation alone may not influence pain perception.

However, patients on antidepressants and those with depression reported higher pain scores when using the red paper compared to the green paper, suggesting that emotional stimuli can impact pain assessment in these groups.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Visual/emotional stimuli and treatment with antidepressants alter Numerical Rating Scale score in patients with chronic pain. Kanai, A., Matsumoto, S., Hayashi, N., et al.[2017]

A new type of artificial light that stimulates color-opponent signals in the retina can significantly advance circadian rhythms, with a study showing an average phase advance of 1 hour and 20 minutes in 6 participants after just 2 hours of exposure.

This light works by modulating short-wavelength sensitive cones, suggesting a novel approach to improving mood and sleep by effectively controlling circadian rhythms, compared to traditional white light which showed no phase advance.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Toward an indoor lighting solution for social jet lag. Neitz, A., Rice, A., Casiraghi, L., et al.[2023]

Customizing a hand-held stimulator with shorter-wavelength blue (440 nm) and orange (590 nm) LEDs allowed for reproducible S-cone ERG responses, which were recorded quickly and showed typical waveforms.

Despite being able to elicit S-cone responses in most subjects, the small amplitudes and high variability of the results limit the effectiveness of this technique for routine clinical testing.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Clinical S-cone ERG recording with a commercial hand-held full-field stimulator. Marmor, MF., Cabael, L., Shukla, S., et al.[2019]

A 66-year-old man with color blindness experienced significant reductions in headache pain intensity after exposure to green light therapy (GLED), indicating its potential as a non-pharmacological pain management method.

The results suggest that GLED may work through non-image-forming retinal cells, while the unchanged frequency of headaches implies that other photoreceptors, like cones, might be involved in reducing headache frequency.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Case Report: Green Light Exposure Relieves Chronic Headache Pain in a Colorblind Patient. Cheng, K., Martin, LF., Calligaro, H., et al.[2022]

In a study involving 72 healthy university students, wearing eyeglasses that simulate watching a large television screen significantly increased both pain threshold and pain tolerance during a controlled pain-inducing procedure.

These results suggest that visual stimulation could be an effective complementary approach to enhance pain relief in various clinical settings.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The application of eyeglass displays in changing the perception of pain. Tse, MM., Ng, JK., Chung, JW., et al.[2004]

Monochromatic light sources with wavelengths under 456 nm are nearly ideal for stimulating S-cones in the human eye, with minimal impact on other cone types, making them effective for electrophysiological studies.

Blue light emitting diodes (LEDs) with a peak wavelength of 448 nm and a bandwidth of 25 nm provide approximately 95% S-cone activation, while other displays like the Trinitron monitor and multimedia projectors also show high activation rates, indicating their suitability for S-cone stimulation.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Spectral characteristics of light sources for S-cone stimulation. Schlegelmilch, F., Nolte, R., Schellhorn, K., et al.[2019]

The new LED-S photic stimulator can effectively match the stimulus intensities of the traditional Grass Instrument stimulator (GP-S), making it a potential replacement in pediatric visual electrophysiology.

The LED-S provides uniform intensity across its surface and can generate longer stimuli, which may enhance the quality of electroretinogram (ERG) recordings compared to the GP-S, which has a significant central hot spot.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

A comparison of the Grass strobe and new LED photic stimulator for paediatric electroretinogram recordings. Liasis, A., Gruszewski, J., Toro, J., et al.[2021]

Phototherapy, particularly using different colors of light, can modulate pain perception by affecting specific neural populations in the ventral lateral geniculate body (vLGN), with green light promoting antinociception and red light potentially increasing pain sensitivity.

The study utilized fiber photometry and chemogenetics to show that green light enhances glutamatergic neuron activity while red light increases GABAergic neuron activity in the vLGN, suggesting that light color can be strategically used to develop new treatments for neuropathic pain.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Glutamatergic and GABAergic neurons in the vLGN mediate the nociceptive effects of green and red light on neuropathic pain. Wu, XQ., Tan, B., Du, Y., 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. ctv.veeva.com ctv.veeva.com/study/chromatic-retinal-stimulation-to-reduce-chronic-pain-and-pain-sensitivity

Chromatic Retinal Stimulation to Reduce Chronic Pain and ... Participants with chronic pain conditions including chronic low back pain and fibromyalgia may benefit from light stimuli presented to the ...

2. withpower.com withpower.com/trial/phase-fibromyalgia-6-2023-00861

Light Therapy for Chronic Pain · Info for Participants Research shows that green light exposure can reduce pain intensity in conditions like migraines and fibromyalgia, and a study found that visual stimulation can ...

3. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC10937082/

Effects of Combining Music Therapy, Light ... - PubMed Central This open pilot study supports the idea that LineQuartz® has a place among complementary therapies dedicated to the treatment of chronic pain.

4. clinicaltrials.gov clinicaltrials.gov/study/NCT03677206

NCT03677206 | The Effect of Light Therapy on Chronic Pain The investigators initial target participants with history of HIV, chemotherapy induced peripheral neuropathy and fibromyalgia. Participants will be divided ...

5. sciencedirect.com sciencedirect.com/science/article/pii/S1526590021000250

Mechanisms and Pathways of Pain Photobiomodulation In fact, green light reduced pain intensity in ∼20% of patients having active migraine attacks in the study. The finding that migraine headache exacerbation was ...

6. clinicaltrials.gov clinicaltrials.gov/study/NCT05569486

Elucidating the Central Mechanisms of Action for Green ... Green light emitting diode exposure (GLED) provides long-lasting antinociception in rodents, through the visual system. No adverse effects were noted, and motor ...

7. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC4768515/

Photobiomodulation for the treatment of retinal diseases The stimulation of cytochrome C oxidase by FR/NIR light is believed to lead to an increase in the energy production by mitochondria, increase in the metabolic ...