A surprising development in the area of red light therapy for use in horses was published in 2020. The authors of a study using red and NIR light on wounds that were created on two groups of adult standardbred horses produced disappointing results. They found that there was no benefit shown after using 637nm and 956nm pulsed light on the wounds for 25 days. The results were unexpected and contradictory to all prior experience and testimonials. Many websites followed suit, simply writing off red light therapy altogether as an effective treatment modality for horses, but we would encourage horse enthusiasts to read further before making a decision.
The good news is that there is another study that was done with very similar conditions that showed a marked improvement - in complete opposition to the first study - concluding that "LLLT had a positive effect on healing rate and healing characteristics of DLWs (Distal Leg Wounds) in horses".
Why the different outcomes of the two studies? Perhaps changing the conclusion reached by many after seeing that first study would be the best place to start - that the study did not establish that red light therapy does not work for wound healing in horses, but only that their choice of dosing did not work.
Taking a closer look at the protocol one can see that a fairly low level of dosing was used, even lower than in some studies done on healing wounds in much smaller animals such as rats! The red light's irradiance is reported to have been a mere 2.3 mW/cm2 - only delivering an astonishingly low dose of 0.2 J/cm2. The irradiance from the NIR was not much stronger, only 6.4 mW/cm2 which translated into a total dosage of a mere 1.2 J/cm2 - as treatment was only applied for four minutes a day.
In their meta-analysis review paper, Hamblin et al suggest that "ineffective studies for tissue with lower mitochondria are more likely to be due to under-dosing rather than over-dosing. Fluence and irradiance are both important in determining the success of in vivo studies".
They mention that "Al-Watban and Zhang16 compared the efficacy of accelerating wound healing in diabetic rats using visible and NIR diode lasers at wavelengths of: 532, 633, 670, 810, and 980 nm. Each wavelength was delivered at doses of 5, 10, 20 and 30 J/cm2, using the same power density for all the wavelength of 22 mW/cm2 except for 633 nm (irradiance used: 15.5 mW/cm2) and 532 nm (10 mW/cm2). Results showed that there was a significant difference between the NIR and visible wavelengths with visible wavelengths being more effective than NIR. They also concluded that the optimum wavelength was 633 nm and the optimum dose was 10 J/cm2".
Notably, the successful study on healing distal leg wounds on horses used 5.1 J/cm 2 per treatment with the wavelength of 635 nm and an energy out-put of 17 mW per diode, a signifcantly higher dosage used for 80 days instead of 25.
The importance of dosing cannot be stressed enough and based on this evidence, it is worthy of re-examination of whether the actual treatment or the protocol itself was ineffective. The positive results obtained in the second study would suggest that more research should be done in order to establish the best treatment parameters in terms of irradiance levels, wavelengths and duration of treatment for healing wounds in horses.
The Challenge of Caring for Horses
Whether they are hooved family members or also an integral part of your workforce, we all know that horses can present a bewildering combination of toughness and fragility. This makes taking care of them even more challenging as unlike our canine or feline fur babies, they cannot live in a house with us under our protective eye. They need open spaces and love the company of other horses; so keeping them by our sides or in our houses is not an option.
By nature, horses can be exposed to a level of extreme forces that take some appreciation of the physics involved to understand. Average barn horses easily reach speeds of between 25-35 MPH, whereas athletic horses such as show jumpers and racehorses can hit speeds of up to 45 plus miles an hour. Galloping at full speed is not an unusual activity for a healthy horse, from simply engaging in play with friends to a reaction from being spooked by a loud noise or strange object.
Although horses are made of stronger stuff than humans, a fall can be devastating, and anything from a broken halter lead rope to an errant groundhog hole can lead to a mishap. Additionally, horses have a ranked social system – akin to a herd “pecking order” which can lead to squabbles or even vicious attacks. When horses fight, kicking and biting ensues which can cause bruises, gashes, broken bones and other serious injuries. As such, even the most pampered and best loved horse can be victim of unfortunate circumstances and discovering such an injury while bringing horses in from pasture is every horse owner’s worst fear.
Equally troubling health problems may present themselves in horses caused by routine athletic activities, aging, conformational imperfections, or an unlucky foray into the wrong feed or diet. Medical issues in horses can be difficult to treat due to their size and strength. It can also be difficult to diagnose some conditions - as horses, being prey animals can be naturally stoic as they are instinctively driven to hide signs of pain and weakness from predators. As James Herriot, the famed author and country vet expresses in the title of his book “If Only They Could Talk”.
From a Rouge customer: My dog has some skin allergies and we have been to the vet for meds but we are using the light for faster healing. It’s so easy to set on top of the wire kennel.
Enter Red Light Therapy for Horses
Red Light Therapy may be a great option to consider adding to the repertoire of healing tools in any barn, as it can help overcome the many health challenges horses can face over a lifetime. It is a pain free, non-invasive, and often soothing treatment. It may be a great single or complementary modality alongside your vet’s prescribed treatment. It can offer a relaxing alternative and does not necessitate sedation or unpleasant restraints and has a very good safety profile with no known side effects.
How Red Light Therapy works to benefit your horse:
Light affects us in ways that are not obvious and easily seen, and the same goes for horses. They also like us, have photoreceptors in their bodies and are influenced by different types of light. In many studies, red and infrared light has been found to stimulate the mitochondria to produce more ATP, the very foundation of cellular energy driving all living beings. This in turn spurs faster healing times, reduction in inflammation, higher production of collagen among other benefits. For more on the biochemistry of how light benefits our cells please read this article.
With Red Light Therapy gaining traction as a broad-ranging, effective tool for other family members such as dogs, humans and horses, the research community has yet to catch up to some of the advances in the use of photobiomodulation in treating equine patients. A lack of formal research in the specific area red light therapy and equine health is currently the status quo, however there is plenty of powerful anecdotal evidence indicating its many uses and benefits and the pictures and testimonials in horse forums and other platforms is notable.
Among the available studies, one found that horses with bowed tendon were treated and “results indicate that a significant percent of the standardbreds raced with similar or improved times and classes” click here to read A study of the effects of lasering on chronic bowed tendons at Wheatley Hall Farm Limited, Canada, January, 1983 - PubMed (nih.gov)
In another study, light therapy was used to treat certain lesions in standardbreds - PubMed (nih.gov), encouraging results were seen in a multitude of issues in the standardbreds that were treated.
Vets and other equine health specialists often incorporate Red Light Therapy in their arsenal of available treatments, lending much credibility to its effectiveness in treating horses.
Additionally, we have seen horse owners’ testimonials about the benefits of Red Light Therapy and vets, equine massage and acupuncture specialists often use photobiomodulation to treat the following conditions:
- Sore muscles
- Navicular
- Laminitis
- Hamstring Pulls
- Stiffness
- Inflammation
- Wound Healing
- Muscular injuries
- Tendon injuries
- Ligament injuries
- Bruising
- Arthritis
Often during red light treatment, it is reported that the horse’s eyes are half closed, and their lower lip is loose, a sign that they are in a happy, relaxed state. Chances are, just as humans find that red light therapy reduces stress, so do horse and it is akin to an equine spa treatment!
Your Horse Might Even Share Their Red Light Therapy Panel With You
You can choose from our family of panels to decide which one would suit your horse’s needs best. We believe that a gentle red light therapy treatment will be well received and make a great gift for your horse!
Can red light be used for ring bone?