Comment on Canine Degenerative Myelopathy Paper

Hi Everyone.

I have had a few people ask me my opinion on the Dr Lisa Miller’s paper on PBM for Canine Degenerative Myelopathy.

The paper, one of many reviewed by Drs Millis & Bergh, was given this accurate if rather terse summary:

‘A study of laser use in treating degenerative myelopathy did not have a control group (comparison to a historical control group was used), had other confounding factors that may have influenced the results, and the laser dose used to compare Class III and Class IV lasers was not the same. The risk of bias for the study came in as high.

In fairness to the paper, despite it being from a competitor company-I don’t think we should dismiss Dr Miller’s findings based on the above reasons.

To put the comments into context: Drs Millis & Bergh had undertaken a systematic literature review in general for PBMT and found gaps in the scientific documentation. Conflicting study results and unclear application for clinical use are explained by the wide variety of treatment parameters used in the analysed studies, such as wavelength, laser class, dose, and effect, as well as the frequency and duration of treatment. Some beneficial effects have been reported during treatment with light therapy; however, the published studies also have limited scientific quality regarding these therapies, with a high or moderate risk of bias. Although some beneficial effects were reported for light therapy, the studies also had limited scientific quality regarding these therapies, with a high or moderate risk of bias.

In general, I would have to agree with Dr Millis and  Dr Bergh’s findings on most of the clinical papers out there in the PBMT field. The standard of publishing for PBMT is nothing like the ring mill the AVJ or EJFM etc puts you through to get a veterinary paper published with them.

Pure Science Research PBM papers focused at the cellular level, however, do tend to hit a higher standard.

So where does that leave us with Dr Miller’s paper?

1)Tacit Knowledge: What you know from being in the field, not from a textbook.

Our own knowledge of using our PBM machine on German Shepherd Myelopathy is that the therapy does work. The therapy should be added as an adjunct therapy-it doesn’t replace Megaderm, Denosyl, NSAIDS, Rehab, etc but PBMT alone, delivers about 70% of the total successful response.

2)Scientific Knowledge.

We know CDM disease is a mitochondrial-based disease with superoxide dismutase1 mutation being the fault line.

We know PBMT targets mitochondria very efficiently.

We know muscles and nerves have a high mitochondrial load.

Therefore PBM therapy has a natural scientific ‘in’ or ‘back door’ to this disease.

Conclusion. The findings of Dr Miller’s paper are worthy of application in general practice.

Reading list.

  1. Miller, L.A.; Torraca, D.G.; De Taboada, L. Retrospective observational study and analysis of two different photobiomodulation therapy protocols combined with rehabilitation therapy as therapeutic interventions for canine degenerative myelopathy. Photobiomodul. Photomed. Laser Surg. 2020, 38, 195–205. (Attached above)
  2. Canine degenerative myelopathy: a model of human amyotrophic lateral sclerosis Raffaele Nardone

et al . PMID: 26432396 DOI: 10.1016/j.zool.2015.09.003

  1. Mitochondrial dysfunction and amyotrophic lateral sclerosis

Isabel Hervias et al . Muscle Nerve 2006 May;33(5):598-608. PMID: 16372325 DOI: 10.1002/mus.20489

  1. Pre-exercise low-level laser therapy improves performance and levels of oxidative stress markers in mdx mice subjected to muscle fatigue by high-intensity exercise. Paulo De Tarso et al. Lasers in Medical Science30(6) 1007/s10103-015-1777-7
  2. Evaluation of inflammatory biomarkers associated with oxidative stress and histological assessment of low-level laser therapy in experimental myopathy

Natalia Servetto et al l

  1. Low-level laser therapy (LLLT) prevents oxidative stress and reduces fibrosis in rat-traumatized Achilles tendon Fillipin L. et al.
  2. Millis D, Bergh A. Systematic Review A Systematic Literature Review of Complementary and Alternative Veterinary Medicine: Laser Therapy. Animals 2023. 14;13(4):667.doi:10.3390/ani13040667

Avoid Tunnel Vision with Laser Treatment Options

Don’t get Tunnel Vision.
Laser therapy is so much more than an anti-inflammatory tool. Rather than ask “What can I use laser on?”; take a moment to consider “What can’t I use laser for?”
One then very quickly realises there are very few presentations that laser therapy can’t be added on as an adjunct therapy.

From reducing action potential in nerves to decreasing muscle spasms, trigger points, and tissue oedema, your laser therapy machine can be factored into minor-major disease and injury presentations.

Enjoy the versatility of this non-invasive modality, that is without peer in terms of capital equipment expenditure and client/veterinarian/pet benefit.

ARWLaser Image

Let Lunchtime Focus on Food not on Facts

Our Vets at Vets1laser know the importance of keeping the focus of a busy clinic’s lunch times as a time for all staff to catch a breath and eat. Lunchtime is best spent taking in food, not taking in facts. Forget a Demo at lunchtime! Organise a time that best suits You, to learn more about all things Class IV Laser/PBMT. Contact us at [email protected] to find out more about how Vets1laser can be a game changer in your daily clinic or hospital schedule.
Winston Blue jacket

Laser/PBMT for The Athletic Animal

Laser/ PBMT for Injury Risk Reduction in The High-Performance Animal Athlete.

In addition to treating pain and inflammation, Laser/PBMT can assist in preventing inflammation and pain and help support performance.
In the canine athlete, a Laser session the day before and the night of a demanding day event can prove beneficial. A treatment session the day before allows the body to respond to the positive sequence of events intrabody that occur with PBMT and opens access to the ergogenic benefits of the therapy.

A post-event treatment session provides anti-inflammatory benefits to the body structures that underwent high intensity and heavy workload during the athletic event, thereby speeding recovery and reducing the risk of an undetected injury being overlooked. 

However, Laser/PBMT is not a therapy tool that should be used to rush an injured animal back into competition. Healing takes time and all animals should be given the time to heal in peace.

Studies in human athletes have shown that PBMT has proven benefits as an ergogenic aid to therapeutic exercise; which translates into longer before you hit exercise-induced muscle fatigue, less muscle damage, and an increase in achievable muscle repetitions during exercise.
Post-exercise, PBMT can help prevent muscle soreness and pain after excess exercise, facilitates post-exercise recovery, and supports and fastens the healing of an injured muscle.
Age was not a limiting factor, indeed the older the cohort, the greater the relative response to PBMT.
Image courtesy of fFire Photography.

Mia cat on side (2)

Top Tips For Feline Laser/PBM Therapy

Tut-Tuts and Top Tips for Laser /PBMT Treatment of our Feline Patients.

One of the biggest misconceptions out there is that cats won’t tolerate Laser therapy. Contrary to what you may have been told, Cats will tolerate Laser therapy but on their terms.

So, to help colleagues abide by those feline terms, I have put together a six-point treatment checklist for Vets to be aware of before they start any Laser treatment on any cat.

 PBMT/Class 4 Laser: The Seavers Six “ions” for Feline Laser Therapy

  1. Preparation

You must adjust the treatment room to allow the cat to first settle i.e., the CDFH rules of cat consultations.

If you have a cat-friendly practice-chose the calmest area to park your Laser machine. Play Calming music in a Darkened room with the Heat and the Feliway pumping.

  • Use the knowledge that Cats have an absolute,1,2 requirement for heat with a preference for areas with an ambient temperature of >32C to your treatment advantage.

In our clinic, we used warm heated covered beds on our tables for all our cat patients, regardless of presentation, so Laser therapy patients should not be treated any differently. These small beds were strictly cat-use only to avoid any contamination from stressful dog pheromones, plus the removable fleece covers were quick & easy to wash and rotate. Have the heated beds also sprayed with Feliway & catnip and even nervous cats will learn to settle. The nervous cat in the 3 images below went from panicked to smooching in a very short space of time once he was allowed to have a moment to acclimatise to his surroundings and settle on the warmed pheromone-rich mini heated bed on the consult table. Sensory-Sympathetic Coupling translates as emotional arousal worsening pain, so the more anxious the cat the worse its pain. Stress enables an amplification of pain so set your laser session up for success by first reducing known stress triggers in your treatment arena.


  • Once the cat has settled, either Zoom Groom or massage the cat on a body site well away from the presenting treatment site.
  • If this is a chronic case being treated for the first time am recommending starting with a puff of air, breeze, or feather test on the injured area to flush out if allodynia is an undiagnosed major concern for this cat. If no aberrant response to the airflow past test-then put the pet goggles on the cat.
  • Goggles.

Most cats are not bothered by the G.oggles. Some cats are really calmed down by having the goggles on. However, on the rare occasion that a cat does not tolerate the goggles, use the principles of the calming ‘burrito’ wrap to cover the cat’s head in a heavy black cloth and tuck the head and neck gently back in under the owner or assistant’s arm. Black micro-fibre cloth provides a 75% loss of power whilst blue Denim cloth runs at an 88% loss of power. An easy solution is to cut off the leg of a pair of black denim jeans (wide-legged jeans are even better and infolded) to slip loosely over the front part of a cat that you can’t tightly wrap due to pain issues.

Only then, do you now apply the Laser to the affected area.

During the Laser application time, depending on the cat’s temperament and the treatment lesion location, you can additionally distract the cat with a treat lick mat or food toy.

2) Program Selection.

For cats- the duration of the treatment session has to be short.

The old Veterinary Maxim that most cats will give Vets 3 minutes max stationary before objecting, means you need to be using Veterinary Laser machines with abilities to do a full treatment program in under 5 minutes. Nowadays that is easy to achieve as many of our pre-set programs average running over a 1-2-minute session. The 5-minute Class 4 treatment sessions tend to be reserved for really large lesions or areas; wherein the cat either has had some sedation to be handled or is just not inclined to want to move around anyway, so more cooperative in general.

3) Application

Again, here the Laser rules of a dynamic 360 circumferential grid application have to be tempered by the species treated.

Initially, we are happy to just cover as much of the damaged area as possible without the need to move the affected limb through its range of motion. Rather, we move around the area or adjust the cat bed, but try to leave the cat with minimal handling.

The aim is always to try and cover regional lymphatics, trigger points, nerve tracts to the area, and upstream and downstream anatomical secondary and tertiary victims of the initial primary injury. Often this ideal is not possible on any patient in the first couple of sessions, so consider targeting those areas as the primary lesion becomes less painful. Conversely, with all things feline-sometimes it’s the upstream major nerve tracts entering the injured area and or the draining lymphatics or supporting connective tissue outside the area that the cat will initially only allow to be treated.

3a) Contact; Easy goes it!

Even if the head of the handpiece of your particular machine needs to be in contact with the cat-that doesn’t mean you have to need to dent the poor cat!  Everyone has an individual tolerance level not only to pain but also to pressure. I have seen videos of heavy-handed veterinary operators using a contact head and they look like they are plowing a field, not applying a therapeutic modality to a living body part so no wonder the vet patient objects. There are many levels of massage intensity but very few veterinary patients should be subjected to the higher level, painful massage techniques as the vet patient is not an equal player in the massage therapy as the human patient is.

A lot can be done with the lightest of touches so go easy and go gently, especially on the first few outpatient visits.

If the cat will not tolerate any touching of the area at all, in the acute presentation off-contact for the first couple of sessions until the primary lesion is less painful. There are now several veterinary machines out there that have both on and off-contact heads.

For my laser vet users, I teach the E.O.O. Rule to know when to select the off-contact method. If you can see the area with your Eyes and or you think /verbalise an ‘Ouch’ when you see the injury-then select Off-Contact. Such areas would be burns, wounds, abscesses, etc., or a deeply distressed patient.

The cat might allow you to do on-contact for the 2ndary & tertiary areas or on the intervertebral area and exiting nerve that supplies the diseased areas.

In the chronic presentation, wherein the cat is not tolerating the Laser, the lesions themselves can have undetected allodynia in full swing. These allodynia patients will have a truly adverse intolerable response to any applied pressure and even initially to off-contact treatment.

4) Repetition

The feline treatment regime, unlike dogs-should, perhaps not be done daily but rather wait and repeat after a recovery phase of 48-72 hours.

Why are we recommending this longer gap, when the textbooks say cats can have daily Laser therapy sessions?

We currently recommend this 48–72-hour gap for a myriad of reasons:

  • Cats are very vulnerable to stress in general, from oxidative stress to behavioral stress.

Users of older Laser model machines had concerns that daily use put the cat in an oxidative stress zone and so they recommended a 48-hour frequency.

  • With allodynia cases, a percentage end up having a bad day following the initial session but over 48 hours will begin to really benefit with dramatic drops in neuropathy. By that stage, you have a much less uncooperative patient than if you rushed the cat back in 24 hours later whilst it was still in the post-treatment storm. The rebound storm issue, though rare, appears to occur on the first treatment of a chronic case-not in subsequent sessions, hence why important to pace and space where you can.
  • Behaviour Specialists talk of it taking a cat up to 72 hours to recover from the stress triggered by any Vet visit, which leads us to owner Behaviour.
  • Cat Owner compliance every 24-48 hours is poor.

This owner’s reluctance is due in no small part to their cat still recovering from the previous Vet visit. This lag phase to normalcy very quickly stops the owner from representing the cat for regular daily or every other day treatment session.

  • Historically, 72 hours seems to be the feline drug therapy ‘sweet zone’…

You can decrease the gap to 12-48 hours in Acute presentations, where if you either feel the lack of response or the degree of disease/injury presented is such as to merit an initially higher level of intervention.

In those ill cats, most are admitted to hospital wherein attention to the provision of supportive therapies, biochemistry screen trends & antioxidant medication is the norm and so lessens any concerns in general.

  • After two weeks, move out to once weekly then fortnightly, etc., or as your individual patient’s needs dictate.

Currently, in the absence of sufficient peer-reviewed studies on cats to absolutely state 24hr-48hr frequency gaps, we are erring on the side of caution and advising routine treatments have a 48-72-hour gap. Over time, as peer data flows in more and more, we may change this recommendation, but currently, Primum Non-Nocera has to be the first rule of any therapy consideration.

5) Sedation

If you are using the Laser on any sedated pet-and hence a patient who cannot actively remove itself from the treatment field- and especially if you sedated this cat to shave/ clip it-then always use a trailing finger to monitor the treatment intensity.

6) Clipping Fur Question

Q: Do you still need to clip the pet’s fur before Laser therapy?

A: No, you don’t routinely need to shave the pet.

Once upon a time, shaving was needed but no more. The evolution of modern Class 4 Laser machines with in-built protocols factoring in colour, coat, body size, etc. to pre-select the correct parameters for delivery and wavelength to maximise absorption by the target tissue means most pets no longer need to be shaved pre laser therapy.

You can still shave if the hair is overly long and matted or filthy.

Not needing to shave a car greatly increases owner compliance and reduces Veterinary staff stress considerably.

If you are concerned about the depth of coat-a very very light spray of water to dampen the area will help.


Don’t shave,

Provide a calm safe zone,

Check for allodynia,

Allow the cat to settle,

Select powerful fast sessions and

Space the return visits frequency


We hope the above is of help to all Veterinary Laser users.

At Vets1Laser, we are passionate about putting Veterinarians at the forefront of Laser /PBM therapy.

If you have any different experiences using Laser in cats, we would love to hear from you.

Contact Dr Aine at [email protected] to share and discuss any thoughts or knowledge on all things Laser.


  • Steering the multipotent mesenchymal cells towards an anti-inflammatory and osteogenic bias via Photobiomodulation therapy: How to kill two birds with one stone. Amaroli et al. 2022. Journal of Tissue Engineering; 13: 1–17 DOI: 10.1177/20417314221110192
  • The nuts and bolts of low-level laser (light) therapy Hoon Chung et al 2012 Ann Biomed Eng ; (2):516-33. doi: 10.1007/s10439-011-0454-7.  PMCID: PMC3288797 DOI: 10.1007/s10439-011-0454-7
  • Using Warm tables to ‘Chill’ cats and prevent Actinic skin disease. A Seavers. Control & Therapy CVE Sydney Uni. No: 5733 March 2018
  • Sun-drunk Cats. Control & Therapy. CVE Sydney Uni No:5639. September 2017: Why do Cats endanger their lives in search of warmth?
  • Zoom Grooms. Control & Therapy CVE Sydney Uni: Dec 2007.
Bengal Love heart

Problem Solving Part 2: Safety in Numbers

Part 2: Patients not accepting the Laser Application.

Be a Veterinarian and adjust your treatment protocols to your patient, just as you would any other treatment or disorder. There are no fixed ‘recipes’ when it comes to Laser in our pets: it must remain a dynamic and individualized treatment per patient that evolves as the patient needs demand.

However, if you are finding your patients are uncomfortable when you yourself use a pre-programmed protocol, (as many different models of Veterinary specific Laser machines have), best before you consider dropping the dose down, to first recheck your patient’s risk factor for allodynia, and check your own technique and that of your technicians.

Protocols provide proven consistency and accuracy so if you alone are having issues, don’t rush to change the therapy delivered.

  1. Dropping the Dose: This Should Not be Your First Option.

Too low a dose will not be therapeutic; you need to ensure you are getting adequate dose delivery to ensure a therapeutic response.

  • First run a self-assessment checklist on the protocol selected and your scanning speed, application pattern, and angle of your actual technique, before you consider changing a pre-set program setting, with which no other therapist has had issues.

A quick revision & checklist of the rules of Laser use during a dummy run could pick up where bad habits have developed in how you hold or use the Laser tool.

  • Equally review the program selections you are choosing and check that the program you have selected is actually correct for the lesion or area you are treating.
  • Remember that an allodynia patient’s reaction may have nothing to do with the pressure or the power setting, but simply because the brain has taken the heat signal and ‘dressed and expressed’ it as pain.

Turning the power down won’t address the allodynia-in fact it could make it worse.

We know Laser efficacy is directly related to the strength of the Laser. Applying weak ineffective doses because you incorrectly deducted that your chronic lesion patient can’t tolerate the fluence and irradiance you selected could result in poor end results.

  • If initially blowing on the skin of these uncooperative patients when the pet is conscious, then triggers an abnormal response: sedate the pet and warn the owner the issue can be worse for 36hrs before improvement is seen. Otherwise, if you start with the Laser beam first and get the allodynia-then the pet and the owner associate the Laser with an adverse response and neither will return to your clinic.
  • If you are using on-contact and having issues-just use the head first without turning the machine on. If your patient doesn’t tolerate just the application of the head, the issue is not with the Laser but with the therapist or the patient.
  • If the pet tolerates the head, but not the Laser beam, then review all of the above again.
  • Once you have checked all the above boxes and found all to be correct, immediately contact your own particular Veterinary Laser machine supplier and directly discuss your findings with them. It may be your machine needs an update, or it may need to be swapped out for a week with another machine to ensure your machine does not have an individual fault

Only after all of the above is completed, should consideration be then given to the use of a much lower dose than the norm.



Problem Solving Part 1: Can You Have Too Much of a ‘Good Thing’?

Veterinary Laser/PBM therapy is still very much in the Frontier Medicine category, so it is imperative that we, the Veterinary profession, as The Animal Advocates, maintain authority over how and where this therapy is used.

Veterinarians, when taking on new technologies such as Laser therapy, must remain healthily wary about linearly extracting & extrapolating data re dosimetry and frequency etc. from Human Laser therapy, straight across onto our Veterinary patients.

It has now been over 4 decades since cats were treated by Vets as small dogs or shrunken hairy little people. It has been over 3 decades since we as Vets considered all canine breeds the same re physiology & biochemistry & pharmacology. Yet, out on the road during a recent trip calling into Veterinary clinics to demonstrate our particular Laser machine, I heard time and time again, of non-Vets giving human field Laser treatment advice to other Veterinary Laser users, without any thought or knowledge of the inter and intra-species variations of our Veterinary patients.

Even though our Vets1laser users per se are not having the issues reported below-in order to protect PBM therapy from getting bad press and to protect our veterinary patients from insufficient or excessive exposure, we have written the following set of open posts to help Veterinary Laser users problem-solve issues the way Veterinarians should and would do.

 Trouble Shooting Cogitations

Part 1: Increasing the Treatment Session  Frequency to 3-4 times a day?  No!

You can have too much of a ‘Good Thing’.

We prefer to pace out the therapy sessions due to species-specific idiosyncrasies and to give the body time to respond to the cascade and chemical responses triggered within it by each Laser therapy session However, we now note a recent trend to move to more frequent use, regardless of the species being treated, with recommendations to administer therapy every 6-8 hours in some presentations.

This is a cause for concern, akin to the incorrect belief, “Well if some works, then more must be better” and we all know that is not true.

PBM may not be a primary chemical or a pharmaceutical drug, but for many PBMT is regarded 1,2 as a ‘Drug-therapy Equivalent.’ PBMT may not elicit the same side effects as mainstream drug therapy but that does not mean we can abandon any concerns about potential, as yet unknown, side effects.

PBM modulates the ancient primordial1,2 photoacceptive properties of known powerful intra-body molecules to modulate metabolic and oxidative pathways and the cellular signalling responsible for the survival or death of a cell. What we don’t know is whether other photoacceptors are in that area., if they are also affected by light therapy-perhaps adversely especially if their threshold is exceeded wherein, we could inadvertently target prokaryotic or neoplastic cells.

Mitochondria are the main target of the therapy3. As both the major production and scavenging site of reactive oxygen species, mitochondria maintain a tight balance between the two, a balance that is critical for ROS-dependant signalling and for avoiding free-radical damage that leads to cell death3.

The site you first start treating is not the same site you come back to 6 or 12 hours later. Changes have occurred in that time, are occuring or need time to occur so when you come back to treat too early, then you either negate the benefits of the earlier session or could indeed be causing some toxicity in the cytosol.

On a microcellular in vitro level, we know for mesenchymal stem cells(MSC) a single NIR stimulation will produce the most prominent effects on mitochondrial membrane potential and ATP generation between 3-6/7hours post treatment4

In a study on Rat bone marrow MSCc exposed to a single NIR treatment, an increase in cell proliferation persisted for 48 hours.

A study on geniculate ganglion neuronal cells and the effect of PBM on apoptosis, the change in the ADP/ATP ratio took 3 days to become evident. (5)

Each laser session induces a reaction in the body: you need to give the body time to work on these, now intra-body, chemical/neuromodulation cascading events. The toxicity risk of any medicine is proportionate to the actual dose, both as a stand-alone dose and as a cumulative risk- and PBM/Laser therapy is no different.

Four species concerns come into play.

1)Birds have a high metabolism to start with. Adding in multiple PBMT sessions in a short period has to carry some risk of overstimulating the bird’s metabolism.

2) Cats are very vulnerable to stress in general, from oxidative stress to behavioural stress. Users of older model laser machines had concerns that daily use put the cat in an oxidative stress zone and so they recommended a 48-hour frequency.

With allodynia cases, a percentage end up having a bad day following the initial session but over 48 hours will begin to really benefit with dramatic drops in neuropathy. By that stage, you have a much less uncooperative patient than if you rushed the cat back in 24 hours later whilst it was still in the post-treatment storm. The rebound storm issue, though rare, appears to occur on the first treatment of a chronic case in subsequent sessions, hence why important to pace and space where you can. Behaviour Specialists talk of it taking a cat up to 72 hours to recover from the stress triggered by any Vet visit, so always good to space the timings.

3)Dogs. When acute ill or badly injured, dogs often go into a metabolic hold, whereby the body expresses a ‘low T3 syndrome’4 to act to limit protein loss by decreasing metabolic rate during chronic or severe illness. Ramping up the metabolism, even focally, by the application of multiple Laser sessions in 24 hours may not be in any patient’s best interest.

4)Humans. On a personal experience level-as someone who has had Class IV laser treatments themselves, not all treatment sessions evoke the same post-treatment response. Sometimes the effect is immediate and ergogenic. Less often, but it does occur, there is a need to curl up and sleep or there can be on occasions, depending on the lesion, unpleasant but not distressing symptoms of mild muscle cramping before muscle relaxation or literally feeling the perfusion resetting back to normal in a limb. Sometimes, one can feel mildly nauseous post-therapy for some hours. When those issues are occurring, or in the case of the veterinary patient with allodynia, the last thing one wants is anyone near them or requiring one to remain still and constrained even for another laser session These issues settle within 24 hours. By then, one is either happy to have another treatment session or be so recovered as not to need a session.

I imagine many veterinary patients would have similar experiences. In fact, some owners do report the pet being less mobile for the first few sessions. This is explained to the owner as an encouraging sign that suggests that increasing blood flow and reperfusion are occurring in that area. Whilst that is true, we also don’t want a reperfusion injury issue situation wherein we have overwhelmed the body’s resources to deal with a sudden demand for toxin removal by over-treating with too many sessions of PBMT.

With the newer suggestion of every 6–8-hour application not based on strong peer-reviewed studies, one has to ask if there is a dosage selection or technique or disease presentation variant contained within the proponent’s findings and hence their recommendations of multiple daily PBM sessions. If so, that recommendation-then truly based on unique operator technique or dosage – may not extrapolate to other users safely but rather as an increased risk of adverse response. Whilst the consideration of the Arndt-Schulz Law, and Hueppe’s Rule suggests it is unlikely to overdose-that doesn’t negate the risk of over-treatment, thus triggering the Law of Unintended Consequences.

 In my opinion, given the current state of knowledge, failing to wait 24hrs between treatments, in all but the most agonising of pain patients, could induce avoidable distress, increase the risk of adverse responses and over time induce habituation.

The existing treatment guidelines have stood the test of time and brought much respect to PBMT. If we intend to change what works, then there first has to be more in-depth evidence providing that the benefits outweigh the risks. Until then, our advice for session frequency still is as below.

Traditional Treatment Frequency

Improve by Four or do No More


Chronic :Every 48hrs x 6-12 treatments

Acute: Every 24hr-48hrs x 6-12 treatments

Post-op: 1-2 Sessions

(For some Dental extractions; wait for 24hrs post-op. Incisions/Dental scaling-Same day).


Gradual decrease to twice a week, then once a week 


Monthly-Seasonal as patient dictates.


  1. Steering the multipotent mesenchymal cells towards an anti-inflammatory and osteogenic bias via Photobiomodulation therapy: How to kill two birds with one stone. Amaroli et al. 2022. Journal of Tissue Engineering; 13: 1–17 DOI: 10.1177/20417314221110192
  2. The nuts and bolts of low-level laser (light) therapy.Hoon Chung et al 2012 Ann Biomed Eng ; (2):516-33.doi: 10.1007/s10439-011-0454-7.    PMCID: PMC3288797 DOI: 10.1007/s10439-011-0454-7.
  3. Eroglu et al. Photobiomodulation has rejuvenating effects on aged bone marrow mesenchymal stem cells. Sci Rep 2021 Jun 22;11(1):13067. doi 10.1038/s41598-021-92584-3.
  4. Ferraresi C et al. Low-level laser (light) therapy increases mitochondrial membrane potential and ATP synthesis in C2C12 myotubes with a peak response at 3-6 h. Photochem Photobiol 2015 Mar-Apr;91(2):411-6. doi 10.1111/php.12397. Epub 2014 Dec 30.
  5. Ferguson DC. Thyroid hormones and antithyroid drugs. In: Riviere JE, Papich MG, editor. Veterinary pharmacology and therapeutics. 9th ed. Wiley Blackwell, Iowa, 2001;745

Reading Material;  

McMillan MW. Surgical Time-Out Procedures. 2023 JSAP:64:69-77

Kim H. et al. Medical lasers 07/2023. Effect of 850nm PBM on adenosine diphosphate/adenosine triphosphate measure of apoptosis in GGNC cells in vitro.

jumping high

Iliopsoas-The Great Impersonator

There is a need to emphasise that many of those ‘arthritis’ dogs that have stopped responding to their anti-arthritis and pain relief medications are often not only afflicted by bone and/or joint pain.
Rather, these patients tend to have concurrent lumbar muscle dysfunction, especially involving the Iliopsoas muscle and often bilaterally. This type of muscular pain is less responsive to classic analgesic drug medication.
This cohort of cases do not need yet more drug medication therapies added to their treatment regime, but rather the addition of a therapy that directly addresses the muscular issue.
Laser/ PBMT is an appropriate drug-free therapy to provide additional analgesia and anti-inflammatory action for this group of patients.
The link below is a link we like to use with our Veterinary Clients when explaining this particular disease presentation in their pets.

CanineWorks-Ilipsosoas: The Troublemaker

Cover Photo by courtesy of Ffire Photography

20210521 00058_1

Introduction to Laser Therapy

Quick Introduction to Class 4 Laser Therapy

Laser Therapy or PhotoBioModulation Therapy is now a well-recognized form of therapy for damaged tissues and structural components(eg joints, bones, ligaments, and muscles). There is a wide range of devices available ranging from simple home-use devices to extremely powerful Class 4 devices that can be used on almost any animal of any size. More recently there has been an increased use of Laser machines in conjunction with Acupuncture and even as a replacement for traditional Acupuncture.

First of we need to give a quick explanation about the types of Laser machines available(ignoring less than Class 3 devices):

First of we need to give a quick explanation about the types of Laser machines available(ignoring less than Class 3 devices):

  • Class 3 machines can produce output at a MAX of 0.5W. This means that they will take a long time to achieve a therapeutic dose in any animal. It also means they are “relatively” safe.
  • Class 4 machines are defined as producing >0.5W and there are machines available with the ability to produce as high as 60W+ continuously. Some Class 3 suppliers will claim that these machines are “dangerous” but if they are used responsibly then there is no problem whatsoever.
  • Some manufacturers use an array of Class 3 diodes to get a higher overall power output but the individual diode output is still only <0.5W
  • Some manufacturers quote “Peak” output as a very high number but then report the average output as a very low number, making it no better than one of the Class3 array machines.

 Why does Power matter?

When applying Laser treatment there are several “parameters” that need to be considered because

Dosage(Joules)=Power(Watts) x Time(seconds)


Number of Photons penetration at any depth is dependent on Power output, a higher power Laser device will deliver MORE Photons at any depth than a lower power Laser device.


Different Wavelengths provide slightly different benefits, although this tends to be less important than the 2 above since most machines tend to use the ideal Wavelength/s as standard.

Recently it has become popular to add “Multi-Phase” but at the end of the day, the first 3 parameters are the most important. When using the machine you would be setting a dosage using these parameters and not concerning yourself with wavelengths or phases as they will be set automatically by the machine manufacturer.

 Typical Treatment examples

Here are some examples, the second being a typical medium to large-sized dog:

600J is suitable for a small dog iliopsoas or I.V.D.D. presentation.

A 1W (max) Class 4 machine will need a 10-minute treatment time versus a Class 4 30W Laser easily delivering 5W and needing only TWO minutes of treatment.

Now consider if you want to deliver 1600J to a larger dog eg. a 30kg dog with a Stifle problem

A 1W (max) Class 4 machine takes 26:40 minutes versus a 30W Laser, delivering only 8W, takes 3:20 minutes to deliver the same Joules. Additionally, the 8W delivery will achieve a much better penetration of the tissues.

For even larger animals, you can simply increase the power, without needing to increase the time. In our experience, most animals will sit still for up to 6-8 minutes. Vets/Nurses can fit in lots of 3-8min laser sessions in a day’s work. (We easily paid for the machine cost in < 12 months)

However, neither the pet nor the Vet nor the Tech/Nurses are quite so keen when asked to sit and reduce productivity for up to 30 minutes at a time, as is required with less powerful, (sometimes) cheaper machines. Class 4 machines can do all that a Class 3 machine does in a much shorter time, plus they have the scope to increase power to treat a wider range of patient sizes and ailments.

Further reading

If anyone wants to learn more about using Laser Therapy then these are excellent resources. They are what we recommend to all new users:

There are other courses provided by them and elsewhere that take more time to complete. They provide courses for Vets and Nurses/Techs/Trainers.

This textbook is a  great reference tool: (cheaper on eBay)

Our Vets1Laser Options

We can supply 2 and 4-wavelength Vets1Laser models and they are both MultiPhase. Our prices are based on the 810nm/980nm Dual Wavelength model which provides the optimal Wavelengths at the full 15W per Wavelength for maximum benefit.

 We can also supply a Dual function Laser machine which can be used for complex Laser Surgery OR Laser Therapy simply by quickly swapping the Optical Cable output.

If you want to discuss more you can contact us through our Contact page above.

Remember- POWER is your friend when you are using these devices for Laser Therapy. 

Larger patients mean you need more power to save time