The Uses of a Class IV Therapy Laser to Veterinary

A Class IV therapy laser is a device that can be used to treat animals with pain or injury. It has been shown to help reduce the amount of medication needed for chronic conditions, relieve minor aches and pains, and decrease recovery time after surgery. 

There are many different types of lasers, but Class IV therapy lasers are high-powered devices that use light waves to generate photochemical effects within tissues both superficial and deep. The result is often a faster recovery but, more importantly, a better recovery. It can be used in acute and chronic conditions in all species of animals. 

This blog will discuss some of the most common uses of Class IV therapy lasers by veterinarians. 

What Is a Class IV Laser?

A Class IV therapy laser is defined as any laser having the ability to deliver more than 500 mWatts of power. The increased power enables the laser to deliver more photons more efficiently and therefore generate a more consistent clinical response. This is especially important when targeting larger patients/body parts, chronic conditions, and deeper-seated conditions. 

Class IV therapy lasers still have the ability to be turned down to very low power as well. Therefore, they can be used to treat problems of the mouth, throat, or skin; stimulate acupuncture points; and even treat corneal ulcers. That may be counter-intuitive to many since directing laser energy into the eye is specifically listed as “contraindication”. But when used appropriately, we have found great success in treating many ophthalmic conditions.

How Does It Work and What Can It Be Used For?

A Class IV laser works by emitting a high-energy beam with specific wavelengths that can saturate the tissue and stimulate a direct photochemical reaction; hence the term-‘photobiomodulation’. Laser energy increases circulation, drawing oxygen and nutrients to the damaged area. It improves the release of oxygen into the tissue and the production of ATP which enhances cellular metabolism. This creates an optimal healing environment that also reduces inflammation and pain.

The following are a just some of the unique procedures that veterinarians treat with lasers:


Benefits of Using a Class IV Therapy Lasers

The use of laser therapy has been proven to be an effective adjunct for veterinarians and their patients. Using a Class IV therapy laser can help patients recover from acute conditions. It will also help manage (resolve?) chronic conditions with less medications. In many cases it also slows the progression of many conditions. 

Additional benefits of using a Class IV therapy laser:

1. Enhanced Clinical Results

Surgical patients and others with acute injury/trauma will have less risk of infection and quicker healing, which means lower risk of complications. Enhanced clinical outcomes foster client loyalty and can result in increased word-of-mouth referrals.

2. Treat Patients Throughout Your Clinic

Class IV therapy lasers can be used to treat patients throughout your clinic. These lasers are portable and versatile enough to be carried to any room of your clinic, including the waiting room. It can also be taken outside to the car or to the patient’s home. It is ideal for the house-call practice or the ambulatory equine practice.   

This versatility and portability allows veterinarians to treat more patients and conditions with a single unit. 

3. Establish a Credibility for Being at the Cutting Edge of Veterinary Technology

Veterinarians can establish credibility for having the most up-to-date technology in their practice, both in the acute and management phases. It’s a technology that has the immediate perception of ‘high-tech’ and ‘cutting-edge’. 

4. Efficient Time Management

With the use of a Class IV laser, vets can treat more animals and conditions in less time.

By using these lasers, doctors will increase the number of patients treated without needing more people to help. It will increase their productivity

Final Thoughts

The use of a Class IV Laser is an innovative and exciting development that can help pets with a wide variety of dermatologic, neurologic, musculoskeletal and even intra-abdominal and intra-thoracic conditions. We have experience using this type of laser on animals of all sizes and shapes. 

The laser is still just another tool So, it is important for veterinarians to understand the proper use, applications, and safety guidelines of a Class IV therapy laser.

In this article, we have described the many benefits of Class IV therapy lasers. We hope this blog post has been an insightful look at the diverse range of applications.

Photobiomodulation: Implications for Pain Relief in Veterinary Medicine…and Beyond!

Laser therapy or photobiomodulation (PBM) continues to provide solutions/options for many intractable conditions. With September’s focus on pain, we wanted to highlight PBM’s analgesic effects. 

The emphasis on managing pain in our veterinary patients has increased substantially especially in the last 8-10 years. Pain causes clinically relevant behavioral and physiologic changes which are detrimental to patient recovery. There are numerous pharmacologic and non-pharmacologic mechanisms for controlling pain with growing emphasis on minimizing pharmacologic intervention thru multimodal protocols. This has reached a critical level of focus particularly on the human side due to the explosive opioid crisis. On October 11, 2018, Congress held its first-ever briefing on ending opioid use through innovative medical technologies for pain management, with PBMT being the featured technology. As our knowledge base increases and the stigma comes down, PBM is becoming a more readily presented option.   

Healing begins at the cellular level. Cellular chromophores within the blood stream and the mitochondria absorb the laser energy. Specifically, it is water (peak at 970-980 nm), hemoglobin (peak at 904-915 nm), and cytochrome-c-oxidase (peak at 790-830 nm) that are being targeted. This causes an improved efficiency of the respiratory chain leading to an increased synthesis of ATP. In addition, reactive oxygen species and NO and SOD are produced and there is a shift in the redox state. A cascade of secondary effects can then take place including DNA and RNA synthesis; activation of fibroblasts, macrophages, and lymphocytes; growth factor release; neurotransmitter release; vasodilation; collagen synthesis; improvement of cell membrane permeability and function of the Na+/K+ pump. Increased metabolic activity will increase oxygen and nutrient availability which leads to enhanced protein and enzyme production. These factors will accelerate/stimulate cell reproduction and growth which leads to faster repair of damaged tissues, moderate the inflammatory response, and provide analgesia.

  These cellular reactions result in three major clinical benefits for the patient:  pain reduction; inflammation reduction including swelling, edema, and bruising; and accelerated and improved tissue healing. These events happen simultaneously and naturally complement each other. 

Inflammation is a result of both vascular and cellular consequences. Photobiomodulation ‘moderates’ inflammation by the following mechanisms. There is production of NO along with other mediators which stimulate vasodilation. This facilitates removal of cellular debris along with activation of the lymphatic drainage channels. But more importantly it reduces ischemia and all the negative events associated with a negative oxygen balance in tissue. Angiogenesis is stimulated as well which increases oxygen and nutrient transport to improve tissue repair and therefore reduce inflammation. Production of ROS and SOD helps stabilize cellular membranes and balance the detrimental effects of free radical activity, respectively. Enhanced WBC activity aids the removal of cellular debris. Lymphocyte activity is mediated to give a beneficial response between the T-helper and T-suppressor cells. There is increased production of PGI2 which has anti-inflammatory activity similar to other COX inhibitors. At the same time, there is a reduction in Interleukin-1 and other pro-inflammatory cytokines.

Reducing inflammation will have a measurable effect on the level of analgesia. There is also direct pain relief especially with the higher dosed regimens. Release of endogenous endorphins and opioids both locally and centrally is stimulated. Laser irradiation suppresses the depolarization of the afferent C-fibers. It helps restore the action potential of the damaged nerve back to the normal healthy level of ~70mV thereby increasing the stimulus needed to produce a painful response. (This relates to our attention to pre-emptive analgesia and preventing the “wind-up” effect.) There is a reduction in bradykinin levels. Axonal sprouting and nerve regeneration will occur and will alleviate the pain associated with the damaged tissue. In addition, the accelerated repair process in general will reduce pain sensitivity related to structural stress and imbalance.     

  All the afore mentioned mechanisms that help reduce inflammation, stimulate angiogenesis and vasodilation, and aid in clean-up of cellular debris, will also increase oxygen and nutrient transport to the area to accelerate and improve tissue repair. Increased ATP production will accelerate cellular function including growth and reproduction. Fibroblast proliferation and collagen synthesis is enhanced and more organized which leads to a reduction of scar tissue and improved tensile strength. There is more rapid epithelialization. Cellular differentiation and maturation increase the number of osteoblasts, myofibroblasts, and other muscle regenerating precursors. Laser therapy can reduce healing times by 30%-50%. It is not just faster healing; it’s better healing! It is this direct stimulation of tissue repair, regeneration, and remodeling that is unique to laser therapy. And this is why we are improving or resolving conditions that were traditionally less responsive before laser therapy was added to our current treatment regimens. And this is why we can manage or resolve many painful conditions.    

Our goal for “pain management” is not to just make the more patient comfortable. We want to get the patient back to their normal activity and/or performance level; restore ROM and improve muscle strength and function; reduce the potential for re-injury; and become an active member of the family again. With the proper therapeutic laser in your armamentarium, you have the best chance of achieving these goals.

Treating Degenerative Myelopathy with Laser Therapy

Degenerative Myelopathy (DM) is an incurable, chronic, progressive, neurologic disease that causes hind limb weakness and eventually leads to complete paralysis. Also known as chronic degenerative radiculomyelopathy, it is similar in many ways to amyotrophic lateral sclerosis (Lou Gehrig’s Disease). The exact cause is unknown but a hereditary predisposition has been identified. It is most common in German Shepherds and GS crosses but can be seen in other large breeds and Corgis. Also, DM usually affects older animals with the average onset age being 9 years.

DM causes degeneration of the white matter of the spinal cord. The white matter contains fibers that transmit movement commands from the brain to the limbs and sensory information from the limbs to the brain. Degeneration consists of both demyelination (stripping away the insulation of these fibers) and axonal loss (loss of the actual fibers) and interferes with the communication between the brain and limbs. DM initially affects the back legs and causes muscle weakness, muscle loss, and lack of coordination with progression over time to complete paralysis. As the disease progresses, the animal may display symptoms such as incontinence and has considerable difficulties with both balance and walking. If allowed to progress, the animal will show front limb involvement. Eventually, cranial nerve or respiratory muscle involvement necessitates euthanasia.

Historically, the average mean survival is only 8-10 months from the onset of clinical signs. There is no effective treatment. However, a study published in the Journal of Veterinary Internal Medicine in 2006 done by Kathmann, et al, showed that intensive physical therapy was able to extend the quality of life and preserve muscle strength. Underwater treadmill, range of motion, stretching, controlled standing routines, core exercises, and walking obstacles were all beneficial. At home therapy is just as critical to success, and affected dogs should be encouraged to be as active as possible.

A recent study published in Photobiomodulation, Photomedicine, and Laser Surgery, demonstrated that intensive laser therapy could significantly increase longevity and quality of life when done in conjunction with physical therapy. The study demonstrated that delivering a very high dose of therapeutic infrared laser energy to the thoracic and lumbar spine along with an intensive rehabilitation therapy regimen provided a significant beneficial effect for these patients almost doubling survival times in many patients. There are several proposed mechanisms of action related to how laser therapy slows disease progression. These would be related to the direct effects on the spinal cord and nerves as well as the benefits to the musculoskeletal system.

Photobiomodulation (PBM) will improve neurologic function by providing anti-inflammatory effects on the peripheral nerves and spinal cord. Laser therapy can slow axonal loss and demyelination. It has also been shown to improve axonal regrowth and nerve function. In addition, it is not uncommon for DM dogs to have other concurrent spinal cord or orthopedic conditions. The laser will have the same benefits in relieving pain and inflammation in the joints and the surrounding soft tissues. PBM can relieve muscle spasms, and trigger points as well as reduce adhesions, and help reverse muscle atrophy. PBM can help remodel the fibrosis in the joint capsule to aid the range of motion, issue a positive effect on the synovial lining, therefore, as well as the synovial fluid, supply a positive effect on the articular cartilage, and can reduce the inflammatory cytokines within the joint. All these aid in improving function, comfort, strength, and mobility- ultimately slowing the progression of DM.

Another key benefit is related to the need for an intensive rehab and physical therapy regimen. Not only has PBM been shown to enhance muscle function and performance, but it has shown the ability to reduce the rate of time of muscle fatigue by improving muscle energy metabolism. It has also been shown to mitigate muscle soreness related to intensive exercise. Studies show that laser therapy will reduce lactic acid and creatine kinase levels normally associated with strenuous activity. It can also speed recovery. Thus, aid the patient’s therapeutic exercise program.

Your Summus Medical Laser can easily be programmed to deliver this therapeutic treatment. The protocol is simple to produce and save in your current laser for use on any size patient using the following guidelines. Start by selecting a chronic back setting for a dark-coated animal and use the edit button to change the phase times and powers according to the following weight class for the patient(s) to be treated- the key is to aim for a dosage range of at least 14-21 J/cm2.


Weight (lbs)             Phase Time(seconds)                     Average Power(W)

15-30                                      108                                         6.0

31-50                                      125                                         7.0

51-70                                      125                                         9.0

71-90                                      125                                         11

>90                                         133                                         12


You would treat 2 or 4 ‘Areas’ based on the diagnosis of structures involved. If there are no concurrent musculoskeletal comorbidities (Unlikely!) then just administer the above, saved programs to areas 1 and 2. Area 1: Thoracic spine from T3-T13. Area 2: Lumbosacral spine from L1-S3.

‘Areas’ 3 and 4 would be treated in any patients with concurrent hip dysplasia, DJD, atrophy, and/or weakness in the hips and rear legs. You would deliver the energy over the hips and proximal musculature in a standard fashion as described. You would use a standard hip setting for the appropriate-sized animal to treat areas 3 and 4 if needed. Area 3 and 4: Pelvis/Hips/Extremities

Recommended Treatment Plan:

Treat every other day or twice weekly for 6-10 sessions. Continue twice weekly or at least weekly indefinitely. Augmenting laser therapy and rehab with nutritional supplements, proper diet, weight loss, and other modalities or treatments can improve recovery even further.

As previously mentioned, for best results, a comprehensive physical rehabilitation program should be instituted in conjunction with laser therapy. This would include both in-clinic and in-home programs. The following procedures are recommended.

In-clinic rehab:


In-Home rehab:


As always, if you have any additional questions, please do not hesitate to contact us! Good Luck!




Hamblin, Michael R. “Photobiomodulation, Photomedicine, and Laser Surgery: A New Leap Forward Into the Light for the 21st Century.” Photomedicine and Laser Surgery, vol. 36, no. 8, 2018, pp. 395–396.


Kathmann, Cizinauskas, Doherr, Steffen, Jaggy. “Journal of Veterinary Internal Medicine.” 2006;20:927–932.

Veterinarians Let’s Talk About Laser Therapy Power

By David Bradley, DVM,FASLMS

There is nothing inherently good or bad or better or worse about a high-powered vs a low powered laser. It depends on what you want the product to do. Laser light is just a part of the electromagnetic spectrum. It’s interesting to note that nowhere else along this spectrum will you have a debate over power. No one will tell you a dental x-ray unit will be able to take an abdominal x-ray; that a 4-Watt light bulb will light up a room as well as a 40 Watt light bulb; that a 2 Watt surgical Laser will cut as fast as a 20 Watt surgical Laser; or that an 800 Watt microwave will cook as fast as a 1200 Watt one. But in the narrow spectrum of laser therapy between 600nm and 1100nm wavelengths, they try and tell you the low powered lasers will do everything the higher powered can do… or more!?  This is some of the confusing (Misleading?!) information out here that jades people on Laser therapy. The question of Power and Dosage continues to come up frequently. Unfortunately, there is still too much misleading or skewed information being disseminated. Here are a few definitions.

‘Power’ is the rate of delivery of energy and is measured in Watts which is 1 Joule/sec.

‘Energy’ is the total number of Joules delivered and is simply calculated by multiplying your power times time in seconds. Power (W) X Time (Sec) = Dosage (Joules)

‘Irradiance’ is the amount of power (Watts) delivered to a specific area. The rate of delivery per area.

‘Fluence’ is the total amount of energy (Joules) delivered to a specific area. In Laser therapy this would be your dose to a given area.

Dosage is calculated the same for all lasers. It does not matter if it is a Class 1M, Class III, Class IV, CW, Pulsed, or Superpulsed. The math and physics related to light penetration and the optics of human skin is beyond the explanation needed here but relates to the wavelength of light which dictates the decay of the incident beam of light as it travels thru tissue. This is calculated by things such as the Boltzmann Transport Equation, Diffusion Equation, scattering coefficient, etc. Obviously, this is an important physical property to consider when determining proper dosage and delivery of laser therapy to a small superficial wound vs a deep musculoskeletal condition.

Irradiance and fluence are what we really care about even though, we often talk just about power and energy. Power only dictates the rate of delivery but is an important component when determining efficiency, efficacy, and safety. (Being able to adjust the power should be one of the features you look for when deciding which laser is best for your practice.) If the laser energy is delivered too rapidly especially to a very small area (high irradiance), then superficial tissue heating certainly could occur. If delivered more slowly and/or over a broader area then all the same positive effects will be experienced but in a larger amount of direct tissue stimulation in a more reasonable time. So, the total energy (fluence) delivered to a tissue or body part will be a direct measure of the irradiance (Power delivered per unit area) at that depth times the time of exposure.
Let’s translate this into something that may be more intuitive; IV fluid therapy. When we IV deliver fluids, we first calculate total dosage. This could be equated to the energy we calculate for laser therapy. This dosage is based on whether we are hydrating a 2-pound kitten or a 100 pound Labrador or a horse. This would be the fluence. If we delivered 60 mls to a kitten, that would be an appropriate total dosage (fluence). If we delivered the same ‘dosage’ to a Lab, that would be much too low (Same Energy or Joules but too low a fluence in laser terms).

Once we calculate the dosage, we then decide at what rate (drops per second or mls per minute) we want to deliver it. This can be considered the ‘power’- the rate of doing work or delivering the fluids. If we deliver the fluids in a normal drip set at one drop per second to the kitten, that would be much too rapid a delivery rate or a very high ‘irradiance’ in laser terms. (At one drop per second a standard IV drip line would deliver 6 mls/minute so the kitten would receive his total daily requirement in 10 minutes!) That same rate of delivery (irradiance) could be just about right for the 100# lab if we wanted to deliver the total daily requirement over an 8-hour day (about 3000 mls). Another very important concept though is that an inadequate irradiance (too low a power) cannot be made up in time. If we could only deliver the fluids at one drop per minute (a very slow rate or very low power), we would never be able to hydrate that 100# Labrador. No matter how long we let the fluids run, at the end of the day we only delivered about 144 mls. Those fluids are being absorbed, dispersed, metabolized by the dog and the rate of delivery for this sized patient (Irradiance) is not adequate to keep up with metabolic demands.

Light works in a similar fashion. Some will use the argument that you can just use the laser longer and it will deliver the same dosage. This is true but they are ignoring the decay of the incident beam as it travels into tissue which is related to the irradiance. Power(W) X Time (Sec) does equal your Joules (Dosage). But just like those fluids being absorbed and dispersed, light is constantly being scattered, reflected and absorbed. It does not just sit there. You cannot turn on a 4 Watt light bulb in a large room and just wait for the room to get brighter. Those photons being delivered at 4 Watts are too low a power (rate of delivery) to fill the room with enough photons fast enough (irradiance) to make it bright. So, you will see a lot of laser protocols that give you the power and the total number of joules to deliver. But this has to be based on the irradiance and fluence or it will not translate into an adequate dosage and therefore a poor clinical response.

Keep in mind that the body also can only absorb so much so fast. So, too rapid a delivery of photons (Or fluids!?) may not allow for full absorption and full benefit. We still need to balance efficiency with practicality and clinical benefits. We make similar decisions regarding the amount and rate of fluid delivery to our patients every day. There is no question that IV fluids delivered over hours (8, 12, 24?) is ideal. Sometimes practicality, patient compliance, or expense dictates that we bolus with SQ. The same dosage may be going in and the patient will benefit but what is the BEST way to get the BEST result.

Dosages listed in the literature, which continue to be studied and actually continue to increase, range from 1-10 Joules/cm2 depending on size and depth of lesion, severity, and chronicity. This mean for a simple wound that is one inch squared it would roughly have an area of 10 cm2. To deliver 1 J/cm2 that would require 10 Joules. With a 500 mWatt Laser that would take 20 seconds. For a 7 mWatt Laser it would take 1428 seconds or 23 minutes! If you want to saturate a deep musculoskeletal area of 500 cm2 with 8 Joules/cm2, that would be 4000 Joules. You can do the math…

Emphasizing once again-even though power times time is your dosage, you can not completely make up for a lack of power with time. Light is constantly scattered, reflected, and absorbed. You have to have a certain threshold of power for adequate results. Just as you could never deliver fluids fast enough to a horse with a 25-gauge catheter or turn on a 4 Watt light bulb in a room and just wait long enough for the room to get brighter; you cannot take a very low powered laser and just leave it in place long enough and hope the energy accumulates, saturates, or reaches the area you want.

This is in no way meant to distinguish or categorize lasers as good or bad. There is no good or bad laser (Although there are some inferior products). This is not a question of high-powered vs low-powered it is a question of dosage and the right tool for the job you want to do. A superficial wound or acupuncture point needs very little laser energy and a low irradiance is often adequate. If you want to get a direct photochemical effect on deep musculoskeletal conditions on larger patients more efficiently and consistently, then a higher-powered laser will be the right tool. And remember, a class IV lasers can be turned down for those very small superficial and/or delicate conditions as well.

Understanding the math and physics related to laser therapy is just as important as the physiology and biochemistry. As we understand this aspect even more, we can better quantify the desired dosage needed for a wider variety of conditions and lasers can be preset to deliver these safely and accurately to simplify treatments. One great consolation is that there is a very wide margin of safety for laser therapy. The improved tissue saturation at higher powers and improved versatility with the capability of delivering very low powers, is what allows a Class IV laser to treat more patients and conditions more effectively in a clinical setting.

Laser Use in Veterinary Medicine-Beyond the Introduction

Surgery and PBM are the two biggest areas of laser use by veterinarians. However, there are other areas where lasers have become an integral part of the veterinary armamentarium.

Veterinarians, as a rule, tend to be resourceful practitioners. They readily adapt and are willing (and sometimes compelled!) to explore alternative methods to improve the health of their patients. In addition, with many owners considering their pets more and more a part of the family, the level of care demanded has driven the incorporation of many technologically advanced modalities for routine diagnostic and therapeutic procedures. These include ultrasound, endoscopy, MRI, CT, chemotherapy, radiation therapy, orthotics, organ transplants, open heart surgery and, of course, lasers.

The most wide spread use of lasers in the veterinary field is for laser therapy; to reduce pain and inflammation and to enhance tissue healing. And it is the healing effect that is most beneficial. Laser therapy directly stimulates tissue repair, regeneration, and remodeling. It allows practitioners to resolve conditions that were traditionally less responsive. In addition, it helps many common conditions heal much faster and much better.

Laser light in the red and near-infrared range is absorbed by specific chromophores in the body (cytochrome C oxidase/hemoglobin/water) and this has a positive effect on specific biological reactions. This photochemical reaction increases blood flow to tissue, stimulates the release of O2 from the hemoglobin delivered, and enhances the conversion of O2 to useful energy by cytochrome C oxidase in the production of ATP. This leads to improved cellular function and/or an increase in cell growth, replication, repair, or production of beneficial biochemical compounds – enzymes, proteins, cytokines, immunoglobulins, DNA/RNA. There is a cascade of secondary and tertiary affects which enhance/accelerate/improve the following physiologic reactions.

Therefore, laser therapy has been advocated for a broad range of clinical applications for pain management, wound healing, reducing inflammation/swelling/edema, and rehab in both large and small animals. Measurable positive results can be seen consistently in the following conditions:

The two most important features that determine the optimum response of a laser are wavelength and power. Laser light in the red and near-infrared range has biostimulatory properties. Roughly, this corresponds to wavelengths between 600nm and 1100nm. The shorter wavelengths are absorbed more superficially and therefore do not have the ability to penetrate as readily as the longer wavelengths. Wavelengths in the visible red range (650nm-660 nm) are highly absorbed by melanin and other superficial receptors. These can enhance wound healing. They may also stimulate trigger points, acupuncture points, and/or cause release of secondary messengers that may improve other deep-seated conditions. From absorption spectra data we know that the wavelengths near the 970nm range have moderate increased absorption by water. With the higher-powered lasers, this can create some thermal gradients and increase circulation in these areas. It is also near the peak of the Hb absorption curve. However, the 905 nm wavelength is even closer to the peak of the hemoglobin absorption curve. Recent studies have indicated that this wavelength creates as much as a 30-50% increase in O2 release to the tissue over the 970-980 nm wavelengths. The most important discovery was related to wavelengths nearer the 800nm range (750-830). These are at the peak of absorption for the cytochrome-C oxidase enzyme. This is the rate-limiting step in the conversion of O2 to ATP within the electron transport cycle. These wavelengths will accelerate the production of ATP within the mitochondria. Utilizing all 4 wavelengths can give you a synergistic effect and/or a wider range of treatment options across a broader spectrum of clinical conditions and patients which will result in better clinical outcomes.

Laser power is the rate at which the Laser energy is delivered. Although seemingly straightforward, the power question seems to raise the most discussion regarding appropriate parameters. The physics associated with laser penetration within non-pigmented tissue is well established and quantified by the rate of decay of an incident beam as it moves through tissue.

Classification of all lasers is dictated by the FDA, based on the maximum power the laser can deliver. It is used for guidance when discussing safety and the potential to cause harm/damage, especially to the eye. Most therapeutic lasers are class IIIa, IIIb, or IV. Class IIIb lasers produce < 500 mW of power (1/2 watt). Class IV Lasers are anything over 500mW of power. Class IV therapy lasers are extremely safe. The main benefit of higher power is the ability to deliver enough photons at the surface (a larger total dose) to compensate for the power loss (decreased number of photons) reaching deeper tissues. This allows for a more direct photochemical response on these tissues. Lower dosages are used when treating superficial wounds/lesions and for acupuncture point or trigger point stimulation. Adjustable power output can make a Class IV laser effective for superficial dermatologic lesions, deep musculoskeletal conditions, and anywhere in between!

Notwithstanding years of research on the bio-stimulatory effects of laser light, we are just starting to realize all the clinical applications for veterinary patients (and humans!). Exciting new possibilities include help with OCD (osteochondritis dessicans), chronic rhinitis/bronchitis, insect/ snake bites, allergic reactions, chronic intestinal or urinary tract inflammation, bacterial/viral infections, and adjunct therapy to improve stem cell results. Laser therapy is becoming standard of care for the control/palliation of many secondary effects related to chemo and radiation therapy in cancer patients. There is optimism for neurologic trauma including concussions, brain ischemia and stroke, peripheral nerve damage, IVDD, and stenosis. It’s worth emphasizing again that laser therapy does not just accelerate healing; it actually improves repair, regeneration, and remodeling of tissue. Post-op complications are reduced. Muscle atrophy can be reversed. Type 1 collagen production yields better tendon and ligament strength and elasticity. There is a positive effect on neurologic function and axonal sprouting. The joint capsule, synovial lining/fluid, and cartilage all benefit. Therefore ROM, function, flexibility and mobility are all enhanced. The potential for re-injury is greatly reduced. Performance animals not only recover quicker but they can regain their competitive edge. Pets can get back to their daily routines and become an active member of the family again.

These are exciting times. Like all technology, lasers have become smaller, safer, more efficient and easier to use. Their broad range of applications makes them not just affordable but profitable. It’s no wonder that lasers are rapidly becoming an indispensable tool in thousands of veterinary hospitals.