Thyroid Blood Testing Timing & PBMT/Laser Sessions

Thyroid Testing & PMBT

When it comes to the harvesting of a Thyroid Blood Screening Test, make sure you are aware of ALL the interfering factors that can give you a non-representative result for that patient. One of those factors may well be the concurrent use of PBMT in the days peri-harvesting the blood screen. 

Photobiomodulation/Class 4 lasers can have impacts on a diseased thyroid gland.  Whilst we have been taught to avoid the actual thyroid gland itself as one of the normal rules of laser/PBM therapy; more recent articles now suggest that PBMT does not cause morphological changes on the healthy thyroid gland. 

However, in the diseased* thyroid gland, PBM therapy can have an actual beneficial effect. In one study in humans, the use of PBMT caused a reduction in the daily dose of thyroid medication. Given that PBMT targets and modulates inflammation and given so many thyroidal diseases are inflammatory or immune-mediated in nature, it makes sense that PBMT would be of benefit, not of detriment, for many of these presentations.

However, the curve ball is that if your patient is on PBM therapy for any reason; be alert that the therapy could alter serum thyroid levels enough that a marginal hypothyroid case might be masked.

If you do run a thyroid screen test, factor in any interference in your serum blood level result.

*Clarification: Never use the laser anywhere near any neoplastic lesion especially if it is a tumour in the thyroid gland i.e. cats.


Laser Spotlight on Hot-Spots

Laser Spotlight on Hot-spots/Pyotraumatic /Acute Moist Dermatitis.

Image courtesy of  Dr Amy Schnedeker.

The opinions expressed here below  are solely those of and not attributable to any other individual.

The ever-increasing emphasis on the need to minimize antibiotics use to guard against disturbance of the balance of the skin microbiome-let alone with the global class actions now being brought against manufacturers of certain classes of antimicrobials for humans- means owners are becoming far less likely to comply with administering any antibiotics to their pets. Therefore, we as vets need to do as much as we can initially with these cases in the clinic so as to set the owner and the pet up for success at home.

I am always a big believer in good old-fashioned ‘elbow-grease’: of getting in and shaving and debriding and cleaning up these ‘hot-spot’ areas before starting any pharmacy. Too many dogs present as repeat sufferers that had no prevention nor proper decontamination done on earlier episodes, leaving their owners expecting their pet would go home on some heavy-duty medications for a protracted period. Not surprising, when the previous treatment focus had been solely on pharmacy.

In addition to the gentle debridement, given more and more Companion Pet Clinics now having Class 4 lasers in their treatment rooms, time to consider using this therapy machine on these skin presentations.

Use the ‘Off-Contact approach’ but don’t just treat the ‘angry’ area. Additionally, treat the peripheral tissue to assist in resolution of inflammation. Treating beyond the lesion boundaries decreases the levels of inflammatory tissue markers swamping the lesion and helps prevent the local nociceptors from firing furiously; which would then have only worsened both  the self-inflected trauma and the overall visual presentation.

I was having this discussion with a very eminent respected Emeritus professor of Dermatology who quite correctly made the additional valid point of needing with Golden Ret breeds (GRB)to ‘remember that the AMD in the golden retriever, particularly on the face/neck/head, may not be pyotraumatic but rather a manifestation of superficial bacterial pyoderma (’.

This is a very valid point about specific breeds and the bacterial aspect as some presentations will need antibiosis. However, it is precisely because of the bacterial component of the disease complex that makes me even more determined to encourage vets who have Red/NIR wavelength machines, regardless of the maker or brand, to expand the vet’s mindset to start using their Class 4 laser machines on cases like Hot spots, etc. not just on pain and joint issues.

It’s important to remember that different wavelengths have different effects on bacteria, viruses, etc. Some wavelengths will indiscriminately sterilize the entire treatment area; a result that one doesn’t always desire. Class 4 Red /NIR machines don’t sterilize a site, these wavelengths don’t directly kill bacteria as the main target is mitochondria, which bacteria don’t contain. Therefore, one is less concerned about wiping out the microbiome with these wavelengths, whilst still getting an antibacterial effect due to improved intrinsic signaling.

In applying Laser/PBMT to these presentations, dependance on the client’s home compliance effort is reduced, the treatment will assist with a reduction in pain and self-trauma and hence a speedier recovery for the patient, so a win-win for all.

The more presentations that are highlighted as valid for non-drug treatment options, the more we can move away from blanket destruction of the microbiome by polypharmacy and instead, support the body to recalibrate the issue back to a healthier balance.

PBMT won’t replace antibiotic therapy where it is needed, but it will eliminate a host of cases where antibiotics might have been unnecessarily dispensed.

Keep It Smooth. Glide, Don’t Gouge. Part 2: On-Contact

The on-contact technique does not mean you need to ‘dent’ the patient with the pressure you apply. 

We have personally applied 1000s of laser sessions to pets with the Vets1laser heads shown, all with  tremendous overall success and yet have never ever needed to apply more than the lightest of contact to achieve treatment success.

PBMT is a photochemical process, it is not a physical massage and it is not a physically uncomfortable therapy.

The technique is done at a specific rate: not super fast and not hovering over the one site. If you have not been taught about speed, direction and grid lines, then ask your own laser company to improve their training to you.

If your patients are resenting the laser when you are using it, then most likely it is operator technique i.e You that is at fault.

Too often we see these sad videos of laser headpieces- from a variety of laser companies being applied to the pet’s body with what amounts to brute force.

To apply laser, one is not ploughing through the animal’s muscles making deep furrows.

Aside from the fact the animal is not an equal player in such a process, unable to call stop if the force applied is too great-there is simply no need for such force to be applied through the end of a good laser therapy head.

If you do have to apply such force for your laser machine head, rethink what you are using.

As like most situations in Vet Med; Its Rarely  about Brute Force and Always about Technique

To see an example gentle low stress on contact technique-watch Dr Mark in this video :

To see a correct off-contact technique, see Part 1 of our ‘Glide’ Blog Posts

Safety First: Otherwise, Run Away

The “I’m Not bothered” attitude about the pet wearing eye protection in a laser session is simply not acceptable.

This is a Safety Issue: You don’t get to ignore the rules.

There are NO situations where it is acceptable for a laser machine to be in use, yet for the animal (or for that matter, any of the humans around that machine) not to be wearing certified protective eye shields.

Eye safety is not negotiable.

I see far too many social media posts of animals not wearing protective goggles or at least a protective shield.

 If the animal doesn’t accept/fit the laser googles-which is very rare, then you should be using the range of eye protection alternatives that your laser supplier informed you about.

All humans in the optical hazard zone must wear eye protection as well. Again, there are too many social media laser posts showing humans either not wearing eye protection or the glasses sitting halfway down their face.

The glasses must be a snug fit and remain so throughout the session.

Given that the optical hazard zone can be up to 15 metres for some machines, the potential for something to go wrong and cause significant optical injury to your co-workers is such that the number of people in the treatment zone is strictly limited to the number of safety glasses you can provide.

Laser emissions in the 810/980nm range are NOT visible to the human eye so be aware of that risk. That is why the red guide emission light is usually at 650nm, which is visible. Light entering the eye from a collimated beam in the retinal hazard zone area is concentrated by a factor of 100,000 times when it strikes the retina so even a low-power beam is a concern. If the eye is not focused at a distance or if the laser light has been reflected off diffuse surfaces, this hazard is greatly diminished, but can still be very dangerous especially as we don’t blink fast enough to stop the damage from Laser. 

The eye will focus a 400-1400 wavelength beam to a very small spot. 

A 1mw beam gives a retinal irradiance on the spot of 1200w/cm2.

Looking at the Sun only gives 10/w/cm2.

Laser machines can be demonstrated in the Off-Mode or Safety Mode: which is how Laser companies can display at conferences etc. This means a knowledgeable salesperson can allow you to handle the machine and try out various steps on the many preset programs without harm before you buy. If a Laser Rep doesn’t know how to allow you to do this, be concerned.   A Laser salesperson can demonstrate a machine running in full operation mode in your clinic so as to perform a treatment session on one of your patients.

A knowledgeable salesperson will never start nor run any treatment session until everyone in the room, including the pet, is wearing wavelength-specific glasses or eye shields. If the salesperson does not insist on this safety approach, be so very concerned to the point of cancelling your demo.

Rest assured none of the above appalling dangerous behaviour is ever something that we would allow to occur in a Vets1laser demonstration.

However, If any of the above had happened with your laser demo from another company that has left you unsure about Laser therapy etc., then please do, as some of our newest most wonderful clients have done, and contact Dr. Aine Seavers or Dr. Mark Weingarth. Our Vets1laser Veterinarians will be more than happy to safely and expertly walk you through all the steps of understanding and implementing laser therapy for your particular practice set-up.


Laser Heads 3

Keep It Smooth. Glide, Don’t Gouge. Part 1:Off-Contact

Whilst Laser therapy per se doesn’t cause damage or worsen an injury, a human operator with poor technique will do damage.
Tissue damage is an operator technique problem. The correct treatment motion is one of scanning the treatment head across an area, not using the head to repeatedly fire on a specific spot.
Exacerbation of a joint or disc problem may well be from a heavy-handed operator. We have seen videos of operators looking like they are using the treatment head to plough through the poor pet’s frame. The aim is to Glide, not Gough the treatment head along the treatment area.
The primary aim of laser therapy is Not massage and certainly never at the intensity level of a Deep Tissue or even a  Swedish massage. Yet, we see cases where the therapist seems to have used the laser tool to apply an unneeded and potentially damaging physical level of tissue compression and manipulation during the laser sessions.
Summary:Keep it Smooth.
                    Scan, Don’t Loiter
                   Glide, Don’t Gouge. 
Check out the short snippet below on the correct off-contact  technique.
Half Page for Vet Expo editon of Vet (Medium)

Vets1Laser at VetExpo 2023

Vets1laser: Australia’s Only Vet-To-Vet Direct Medical Laser Company!
Come See Us Next Month At Booth D62 At The Melbourne 2023 Veterinary Expo.
Our Australian veterinary family owned business offers outright purchase options across our range of machines, along with lease purchase options.
If you are interested in purchasing a top quality laser machine, then join our growing band of Australian (& European) veterinary users.
You will enjoy experiencing our highly qualified Australian Veterinarians share their inter/intra-species variation knowledge to train you and your vet staff in the safest and smartest ways to utilize your new Class 4 laser machine in your Australian vet practice.
Avoid the treatment pitfalls of lay trainers extrapolating human laser knowledge across onto our veterinary patients. Instead have the backup of Dr. Aine Seavers and Dr. Mark Weingarth’s broad veterinary knowledge base to assist you in safely integrating Laser/PBM therapy into your veterinary practice.
Dr. Aine and Dr. Mark are always available for information or support via contact numbers as shown or via our website contact page.

Acute Pain is a Vital life-saving Signal: Chronic Pain is a Vindictive life-damaging Signal

Acute Pain is a Vital life-saving Signal: Chronic Pain is a Vindictive life-damaging Signal

As a profession, we must be as exacting as possible to prevent sustained or chronic pain.

The  Philosophy of recognising the issues of Neuropathic and/or Chronic pain and working to prevent or re-calibrate the response to prevent chronic pain can be as life-changing and often as life-saving as other therapeutic interventions. We must therefore be proactive and pre-emptive in our application of pain relief.

Pain is a multi-step process so Pain relief, therefore, must be multi-modal: but multi-modal must not mean only multi-drug therapy. If, as a profession, we are going to have multimodal pain management within a  ‘Standard of Care,’ then that care must include non-pharmaceutical interventions. PBM may not be a primary chemical or a pharmaceutical drug, but for many PBMT is regarded 1,2 as a ‘Drug-Therapy Equivalent.’

PBM is a scientifically, down to the micro-cellular levels, proven analgesia modality and hence is a powerful tool to arrest and suppress pain and to ward off chronic pain. 

PBMT elicits the same end effects as a mainstream drug therapy by impacting the inflammatory cascade at similar points i.e., decrease in COX2 and Bradykinin levels etc., but achieves that result cua improved intrinsic anti-inflammatory signalling that is generated by better cell metabolism and improved microcirculation at the level of the injured tissue.

PBMT is easily woven into existing pain protocols and should be an absolute ‘Requirement of Care,’ not considered an alternative only when a case fails to respond to previous standards of care.

Neuropathic pain.

We have not paid enough attention to Neuropathic pain/Allodynia in our vet patients. Pain is not just about the pain you feel, but also about how that pain makes you feel…” The brain ‘dresses’ and then ‘expresses’ that pain uniquely in each individual.

As a survivor of chronic pain, I am keen to prevent as many veterinary patients from progressing into a chronic or neuropathic pain scenario. The freedom I get, when PBM releases me from the cage of chronic pain is a freedom that we as Vets should be offering to our patients. The Joy I see PBM therapy bring my veterinary patients- now freed from the virtual cage of pain that is life with unresolved pain-has converted me from a sceptic to an avid proponent of this pain management therapy tool.
We have excused our neglect of considering neuropathic pain in our vet patients as neuropathic pain being a self-reporting condition, so then animals can’t self-report. I disagree. Animals do report back to us that they have neuropathic pain. All it requires is to have an observing and informed mind and suddenly the ‘clinically silent’ presenting case is actually screaming from the roof-tops that it is registering pain, especially allodynia. The animal that: is no longer lame, but still withdraws from contact or inexplicably guards one part of its body, a sweet animal becoming aggressive, a confident animal suddenly fleeing from the lightest touch, an animal who verbalises when a wind blows on its skin or if a blanket is placed on an external body part, these animals are flagging their allodynia

PBM induces normalisation of the microcirculation and interrupts the vicious cycle that originates develops, winds up and maintains pain. Normal physiological conditions of the tissue are then restored which means we have given the patient a head-start in reducing the risk of chronic or neuropathic pain.

As clinicians, to be serious about pain relief, we must expand our therapeutic tools; We have to move beyond the drug cupboard if we are serious about pain relief.

PBM treatment modality is a powerful ally in the drive to suppress pain and ward off chronic pain. If you are uncompromising about pain relief, it the time to add PBM therapy to your therapeutic armoury.

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

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

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.

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.