Near-infrared light therapy for fibromyalgia reaches deeper into muscle, joint, and nerve tissue than red light, directly targeting the widespread pain sites that define the condition. The pain originates in structures beneath the skin, in tissue layers that conventional pain medications reach only indirectly. Near-infrared wavelengths between 808 and 905nm penetrate into these deeper layers, and the clinical evidence reflects that advantage. The largest fibromyalgia photobiomodulation RCT (Silva et al., 2018), enrolling 160 women, used a device incorporating 905nm infrared alongside red LEDs at 11 tender point locations, producing significant improvements across pain, function, and quality of life. Both localized and whole-body delivery methods have demonstrated sustained benefits.
This article is part of our complete guide to Red and Infrared Light Therapy for Fibromyalgia.
Key Takeaways
- Deep tissue penetration: Near-infrared wavelengths (808–905nm) penetrate deeper into biological tissue than red light. Within the optical window (~650–950nm), longer wavelengths scatter less and encounter reduced absorption by surface tissue components, allowing more energy to reach the muscles, joints, and peripheral nerves where fibromyalgia pain is generated (Ash et al., 2017). This makes near-infrared light particularly relevant for fibromyalgia's widespread, deep-tissue pain.
- Whole-body delivery produces durable results: A triple-blinded RCT found that whole-body photobiomodulation at near-infrared wavelengths produced significant improvements in quality of life at every assessment point from mid-treatment through six months after treatment ended, with self-efficacy and fear of movement also showing sustained improvements (Navarro-Ledesma et al., 2024).
- Multi-symptom relief confirmed across nine trials: A meta-analysis of 9 RCTs (Yeh et al., 2019) found large effect sizes for pain reduction (SMD 1.18) and fibromyalgia impact (SMD 1.16), with fatigue, depression, and anxiety also showing large effects across trials that included near-infrared wavelengths.
Why Deeper Penetration Matters for Fibromyalgia
Fibromyalgia pain lives in muscle tissue, joint structures, and nerve fibers distributed across the body. Near-infrared wavelengths penetrate deeper into biological tissue than red wavelengths because, within the optical window of approximately 650–950nm, longer wavelengths scatter less and are absorbed less by surface tissue layers. Computational modelling of light-tissue interaction has shown that red light at 660nm reaches a penetration depth of approximately 2.0mm in skin, while near-infrared light at 850–900nm reaches approximately 2.4–2.5mm (Ash et al., 2017). A fraction of a millimetre sounds marginal on paper. In biological tissue, where energy drops exponentially with depth, it changes which structures receive a therapeutic dose. Empirical measurement of near-infrared laser penetration confirmed this range, with the majority of energy depositing within the first 10mm and residual energy reaching 15–20mm in some tissue types (Kaub & Schmitz, 2022). That depth is relevant to the tender point sites that define fibromyalgia's clinical presentation.
The Silva et al. (2018) trial was designed around this principle. The researchers delivered photobiomodulation at 11 clinically defined tender point locations using a cluster device that included a 905nm super-pulsed laser (delivering pulsed infrared energy at peak powers that enhance tissue penetration), four 875nm infrared LEDs, and four 640nm red LEDs. Combined energy per site was 39.3 J, applied twice weekly for 10 weeks. In 160 women with fibromyalgia, both photobiomodulation alone and photobiomodulation combined with exercise produced significant improvements over placebo across pain (VAS), fibromyalgia impact (FIQ), and quality of life (SF-36). The combined therapy group showed the strongest results, with the authors noting that pain relief in this arm improved VAS, FIQ, and quality of life scores simultaneously. (For the red light mechanisms in these devices, see Red Light Benefits for Fibromyalgia. For a deeper explanation of photobiomodulation at the cellular level, see How Does Red Light Therapy Work.)
Fibromyalgia tender points sit in muscle and fascia, not on the skin surface. A therapy that only reaches the first millimeter or two of tissue is not reaching the structures where the pain is generated. Near-infrared wavelengths get into muscle bellies, joint capsules, and the connective tissue around peripheral nerves. That matters practically because fibromyalgia patients have documented pathology at those depths: reduced energy metabolism in trapezius muscle, small fiber changes in peripheral nerve tissue, elevated inflammatory markers in deep tissue compartments.— Dr. William Carter, MD
Whole-Body Infrared Delivery
A series of trials from the University of Granada investigated whole-body photobiomodulation for fibromyalgia, delivering near-infrared light to the entire body simultaneously instead of targeting individual tender points.
In the initial trial (Navarro-Ledesma et al., 2022), 42 fibromyalgia patients went through a triple-blinded protocol comparing whole-body photobiomodulation to placebo. Pain and quality of life both improved significantly (p≤0.001 for each). The same research group then followed the same patient cohort for six months (Navarro-Ledesma et al., 2024). Quality of life remained significantly improved at every assessment point through six months post-treatment, the most consistently sustained outcome in the trial. Self-efficacy and fear of movement also showed significant improvements from two weeks post-treatment onward, maintained at six months. Pain was significantly reduced at treatment completion and again at the six-month mark.
Worth pausing on what the durability data means here. Symptom recurrence after treatment cessation is one of the most persistent challenges of fibromyalgia management. A therapy producing improvements that hold for months beyond the treatment period addresses a limitation that patients and clinicians deal with constantly.
Beyond the primary endpoints, a separate 2022 trial from the same group found that whole-body photobiomodulation improved circadian blood pressure patterns, pain pressure thresholds, and tissue elasticity in fibromyalgia patients. The circadian finding matters because sleep disruption is one of the core features of fibromyalgia, and circadian dysregulation contributes to it.
The Granada group's results did not stay isolated. A feasibility trial by Fitzmaurice et al. (2023) at the University of Birmingham independently confirmed positive changes across all symptom domains with whole-body photobiomodulation, with improvements sustained at 24 weeks. A follow-up qualitative study (Fitzmaurice et al., 2024) captured something the quantitative data could not: patients described a process the authors termed "recomposition," characterized by increased motivation, improved confidence, and feeling like their former selves. That language reflects genuine re-engagement with daily life, and it showed up without prompting from the researchers. (For the full clinical evidence across all fibromyalgia PBM trials, see PBM for Fibromyalgia: Clinical Evidence. For safety data, see Photobiomodulation Safety for Fibromyalgia.)
Modulating Peripheral Nerve Function
Near-infrared light has demonstrated direct effects on nerve function that are relevant to fibromyalgia's neurological components. A meta-analysis of eight studies (Grayston et al., 2019) comprising 222 participants found that 49% of fibromyalgia patients have small fiber pathology (95% CI: 38–60%). Nearly half. The finding was independently replicated by Galosi et al. (2022) with a larger dataset.
The preclinical evidence for near-infrared light acting on these pathways is building from multiple directions. In an animal model, Chacur et al. (2024) showed that near-infrared photobiomodulation both prevented and reversed neuropathic pain behavior. Working in the Journal of Biophotonics, de Sousa et al. (2018) found that photobiomodulation modulated pain thresholds and neural markers in a pattern consistent with peripheral and central pain pathway modulation. A separate finding from de Sousa et al. (2016) in Neurophotonics added another layer, demonstrating that transcranial near-infrared laser at 810nm temporarily inhibited peripheral pain signaling, evidence that infrared light can modulate pain processing at the central nervous system level.
Fibromyalgia disrupts pain processing at both peripheral and central levels. The preclinical evidence suggests near-infrared photobiomodulation engages both. The clinical data aligns: the 2019 meta-analysis (Yeh et al.) found large effect sizes for pain reduction across nine RCTs, and pain improvements persisted at six months in the whole-body delivery trial.
Addressing Metabolic and Systemic Factors
Fibromyalgia frequently co-occurs with metabolic stress, with obesity prevalence in fibromyalgia populations reaching 35.7% (D'Onghia et al., 2021). A 2025 systematic review and meta-analysis of RCTs (Sun et al.), published in BMC Complementary Medicine and Therapies, found that photobiomodulation significantly reduced BMI (p=0.002), body weight (p=0.004), waist circumference (p<0.00001), and two systemic markers, one measuring inflammation and one measuring insulin resistance, across 11 RCTs in obese patients. The authors rated the evidence quality as low by GRADE criteria and noted that body fat percentage and insulin did not reach significance. The significant reductions in systemic inflammation and insulin resistance are directly relevant to the subset of fibromyalgia patients carrying excess body weight and the inflammatory burden that accompanies it. The included studies used a mix of wavelengths across the red-to-near-infrared spectrum. (For more on how red light therapy addresses pain conditions beyond fibromyalgia, see Red Light Therapy for Back Pain.)
How Infrared and Red Light Work Together
Most recent clinical trials for fibromyalgia have used devices that combine red and near-infrared wavelengths. The Silva et al. (2018) device combined 640nm red LEDs, 875nm infrared LEDs, and a 905nm super-pulsed laser. In the Ribeiro et al. (2023) trial, patients, therapists, and assessors were all blinded to treatment assignment. Photobiomodulation combined with a static magnetic field significantly outperformed placebo across tender point count (p<0.0001) and pain intensity (p<0.0001).
The enzyme inside cells that absorbs light energy has two distinct response peaks, one in the red range (~660nm) and one in the near-infrared range (~830nm). Red light addresses superficial tissue and engages one absorption site. Near-infrared reaches deeper structures and engages the other. For a condition like fibromyalgia where the pathology spans tissue layers and body systems, calling this a "multi-wavelength approach" might undersell it. It is a therapy matched to the biological geometry of the problem. (For a comparison of LED and laser delivery methods for fibromyalgia, see LED vs Laser Therapy for Fibromyalgia.)
Conclusion
Near-infrared light therapy for fibromyalgia addresses the condition where it lives, in deep muscle tissue, joint structures, and peripheral nerves that shorter wavelengths cannot reach as effectively. The clinical trials show significant, multi-symptom improvements from both localized and whole-body infrared delivery, with the strongest durability evidence coming from whole-body treatment persisting at six months. The nerve modulation and metabolic evidence add mechanistic depth, though both areas await direct confirmation in fibromyalgia-specific human trials. For someone weighing whether infrared therapy fits into their approach to managing fibromyalgia, the evidence base is real, the effect sizes are large, and the boundaries of what has and has not been tested are now visible enough to make that decision with confidence.
