What Is Red Light Therapy?
Red light therapy -- also called photobiomodulation (PBM) or low-level laser/light therapy (LLLT) -- is the application of specific wavelengths of red and near-infrared light to tissue. Unlike UV light, which damages cells, red and near-infrared wavelengths interact with photoreceptors inside cells, triggering a biological response at the mitochondrial level.
The science is not new. Research into therapeutic light has been published since the 1960s, and the body of peer-reviewed literature now includes thousands of studies across human medicine, veterinary science, and sports performance. It is used by professional sports teams, physiotherapy clinics, and equine veterinarians across North America and Europe.
Regen Equine RL uses the Tri-Wave Light System(tm) -- a proprietary combination of three wavelengths (660nm, 850nm, and 940nm) applied simultaneously. Most providers offer one or two wavelengths. The addition of 940nm deep infrared is what sets this system apart for conditions involving deep joint tissue, the hoof capsule, and periosteal structures.
Red light therapy is a complementary wellness modality -- not a replacement for veterinary care. Always consult your veterinarian before beginning any new therapy. Nothing in this guide constitutes a diagnosis, treatment plan, or medical claim.
How It Works
The primary mechanism of photobiomodulation is the absorption of light by cytochrome c oxidase -- an enzyme in the mitochondrial respiratory chain. When red and near-infrared photons are absorbed, the enzyme becomes more active, increasing the production of adenosine triphosphate (ATP), the cellular energy currency.
More ATP means cells have more energy to carry out repair, reduce inflammation, and maintain normal function. Secondary effects include changes in reactive oxygen species (ROS), nitric oxide release (which affects circulation), and shifts in inflammatory signaling pathways.
In practical terms, this translates to research-supported outcomes including: faster tissue repair, reduced inflammatory markers, improved local circulation, modulation of pain signaling, and support for nerve regeneration. None of these are guaranteed for any individual animal -- but they are why photobiomodulation has attracted serious clinical attention.
The Bi-Phasic Dose Response
One of the most important concepts in PBM is that more is not always better. Research has established a bi-phasic dose response -- too little light has minimal effect, the optimal range produces the desired biological response, and too much light can inhibit that response. This is why individual protocol design matters, and why Regen Equine does not publish generic dosing parameters publicly.
The Three Wavelengths
Not all red light therapy devices are equivalent. The wavelength determines how deeply light penetrates tissue and which cellular receptors it activates. Regen Equine's Tri-Wave Light System(tm) uses three wavelengths together:
The conditions most challenging to treat in horses -- laminitis, navicular, deep joint arthritis, kissing spine -- involve tissue that 660nm and 850nm cannot meaningfully reach. 940nm is not a bonus feature; for these conditions, it may be the most important wavelength in the protocol.
Conditions It May Support
The following conditions are commonly addressed with photobiomodulation in horses. Research support varies by condition -- some have strong peer-reviewed evidence, others have emerging literature or significant anecdotal support from equine practitioners. All descriptions are based on what the research suggests, not what is guaranteed.
How to Use It
Red light therapy is non-invasive, drug-free, and generally well-tolerated by horses. Most horses relax visibly during sessions -- some fall asleep. Sessions are quiet and stress-free compared to many other treatment modalities.
General Application Guidelines
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1Clean the area. Hair does not need to be clipped -- near-infrared wavelengths penetrate through a normal coat. However, debris, liniments, or thick topical preparations can affect light transmission. A clean, dry coat is ideal.
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2Place the device in contact with or close to the skin. Regen Equine wraps are designed for direct contact, which improves light delivery and reduces scatter. Handheld units are typically held 0-2cm from the surface.
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3Follow the recommended treatment time. Typical sessions range from 5 to 20 minutes per area depending on the condition, device output, and protocol. Do not assume longer is better -- the bi-phasic dose response means over-treatment can reduce effectiveness.
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4Treat consistently. Single sessions rarely produce lasting results. A course of treatment -- often daily for the first 1-2 weeks, then tapering to maintenance -- is how PBM produces durable outcomes. Donna will walk you through the right schedule for your horse's specific situation.
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5Monitor and adjust. Track how your horse responds -- movement, posture, willingness to work, and visible comfort changes. Report back to your Regen Equine and veterinary team so the protocol can be refined.
Frequency by Stage
| Stage | Typical Frequency | Notes |
|---|---|---|
| Acute / Active Injury | Daily or every other day | Higher frequency supports the initial inflammatory and proliferative phases |
| Subacute / Healing | 3-4x per week | Supports tissue remodeling and continued repair |
| Rehabilitation | 2-3x per week | Alongside gradual return to work; supports strength and tissue integrity |
| Maintenance / Prevention | 1-2x per week | For performance horses or chronic conditions requiring ongoing management |
Exact treatment times, device settings, and session frequency are determined individually at consultation. The table above reflects general research ranges only -- not a prescription for your horse. Contact Donna to discuss the right protocol for your specific situation.
Safety & Precautions
Red light therapy has an excellent safety profile when used correctly. It is non-thermal at therapeutic doses -- meaning it does not burn tissue. Horses cannot overdose on heat from PBM devices the way they could from other heat-based therapies.
That said, there are important guidelines to follow:
| Do | Avoid |
|---|---|
| Always consult your vet before starting | Treating directly over active cancer or tumours |
| Protect eyes -- never shine directly at eyes | Treating over the thyroid or endocrine glands |
| Keep the coat clean and dry during sessions | Using over open, actively bleeding wounds without vet guidance |
| Follow the protocol duration -- do not over-treat | Combining with photosensitizing medications without vet approval |
| Monitor your horse's response each session | Treating pregnant mares over the abdomen without vet guidance |
Common Questions
Research References
- Hamblin MR. Mechanisms and applications of the anti-inflammatory effects of photobiomodulation. AIMS Biophysics. 2017;4(3):337-361.
- Ahmed W, et al. Clinical evaluation of photobiomodulation therapy in horses with overriding dorsal spinous processes. Equine Veterinary Education. 2021.
- Luna SPL, et al. Photobiomodulation therapy in horses: effects on pain and inflammation. Photobiomodulation, Photomedicine, and Laser Surgery. 2020.
- de Oliveira RF, et al. Low-level laser therapy in horses: a review of the current literature. Journal of Equine Veterinary Science. 2019.
- Joensen J, et al. Photobiomodulation therapy and the recovery of skeletal muscle in horses. Lasers in Medical Science. 2018.
- Chung H, et al. The nuts and bolts of low-level laser (light) therapy. Annals of Biomedical Engineering. 2012;40(2):516-533.