What Is Infrared Radiation Therapy?

Infrared therapy utilizes light in the infrared spectrum to penetrate tissues, generate heat, increase blood circulation, and stimulate cellular repair. Water-filtered infrared-A (wIRA), monochromatic infrared light (MIR), and general IRR are common forms used in physiotherapy.

Clinical Benefits Across Conditions

 

1. Back Pain in Axial Spondyloarthritis (axSpA)

A 2022 randomized controlled trial by Klemm et al. showed significant pain reduction in patients with active axSpA treated with water-filtered infrared-A radiation (wIRAR) applied locally to the lower back. Pain scores dropped from 4.1 to 2.6 on the numeric rating scale (NRS) over 6 days — a statistically significant change compared to controls.

Key benefits:
– Rapid pain relief (within 1–2 sessions)
– Cumulative effect over multiple sessions
– No adverse effects reported
– Can be administered in outpatient or home settings

2. Postpartum Urinary Incontinence

Combining pelvic floor muscle training with infrared physiotherapy produced outstanding results in postpartum women. The 2025 study by Li et al. found that this dual therapy:
– Reduced leakage volume significantly by 2 months
– Improved pelvic floor strength and urodynamic parameters
– Enhanced quality of life indicators compared to conventional care.

Infrared therapy helped by improving microcirculation, relaxing pelvic tissues, and accelerating repair.

3. Painful Diabetic Polyneuropathy (PDPN)

A 2025 randomized controlled trial using 890 nm monochromatic infrared light (MIR) showed:
– A significant drop in pain intensity (from 7.7 to 4.0 on BPI)
– Improved sleep quality and reduced nighttime symptoms
– Sustained effects even 30 days post-treatment in many patients.

The therapy works by increasing nitric oxide production, leading to vasodilation, improved nerve perfusion, and reduced inflammation.

Mechanism Behind IRR’s Healing Effects

IRR works through:
– Thermal effects: Increases blood flow, removes pain mediators, and accelerates metabolism
– Non-thermal effects: Modulates cellular function, promotes tissue repair, and reduces muscle spasm

The absorption of IRR leads to enhanced mitochondrial activity, resulting in energy (ATP) production and faster healing.

Why Physiotherapists Should Consider IRR

1. Drug-free pain management
   2. Easy integration with existing protocols (e.g., exercise, TENS, ultrasound)
   3. Portable and safe devices for clinic or home use
   4. Scientifically validated across musculoskeletal, neurological, and pelvic conditions

Important Considerations

– Optimal wavelengths (e.g., 890 nm) are critical for therapeutic efficacy.
– Treatment should be consistent (e.g., 2–3 times per week for 4–6 weeks).
– Effects may fade over time without maintenance sessions.
– Best used in combination with physical therapy, not as a standalone.

Final Thoughts

Infrared radiation therapy is not just another tool — it’s a beacon of hope for many chronic pain and rehabilitation patients. As research continues to unfold, integrating IRR into physiotherapy protocols may become standard practice in enhancing recovery, reducing pain, and improving patient outcomes.