Great, well, we're all ready, we're we're started. Great to have you all on this evening, and we're gonna be talking about use of inhaled medications to treat respiratory disease in dogs and cats, which is being sponsored by Breathe Easy today. We're very very fortunate to have Phil Padrid on today, who is going to give the talk and Phil actually graduated from Cornell.
University, which of course, as you know, Phil, that we, we always say it's gorgeous, don't we, because it's it's a beautiful place. And, Phil then went on to work at UC Davis for a number of years doing a a residence. And then did a postdoctoral fellowship in the division of pulmonary and Critical Care Medicine also at UC Davis.
He's had various other positions, but now is working as the regional MD for 14 specialty hospitals in the south west and Southern California region for the VCA organisation in America. I'm really looking forward to this. This is something that I've not really done much of during my practising career, so I'm, I'm, looking forward to learning lots, Phil, so it's over to you.
Well, thank you so much, Doctor Chadwick and thank you, the virtual Congress for inviting me this year. This is a lot of fun. It's noon my time.
I understand it's 7 o'clock yours, so I guess we'll get towards it. The agenda for the day is on the slide. We'll talk about the history of.
Phil, I think you've just muted. It might have been just on your. Your height set.
Am I good now? Yeah, that's fantastic. Thanks.
The agenda for the talk is on the slide. We'll talk about the history of inhaled medications, the theory behind why they're even used, specifically why some drugs are chosen. We'll talk about the indications for their use in dogs and cats.
We'll talk about how to administer these drugs, we'll specifically talk about whether or not there's definite proof that they're effective and finally on a very practical level, we'll talk about their cost. In terms of the history of use of inhaled medications, I just recently learned this that Hippocrates, who was the Greek physician 460 to 370 BC, was the first person recorded to link asthma symptoms to environmental triggers. Now how we actually know that I didn't check, but it's in, it's on Google, so it must be true.
In Egypt in 1500 BC they Threw black henbane weed on the hot bricks and that vaporised alkaloids and people with asthma and other respiratory conditions were supposed to take a deep breath. In 1834, Francis Ramage developed an inhaler for consumption, which was the older term for tuberculosis, and it was a tube that patients would inhale slowly and. They put into that two vapours of tar, iodine, chlorine, hemlock, turpentine, and others, and if you know anything about most of these ingredients, I don't know that many of these patients survived, but that's the history.
These are some of the older vaporizers that were used in the upper left. This was made in 1858. In the middle was a vaporir used in the 1930s to inhale adrenaline.
And in the bottom right they have asthma cigarettes and again alkaloids of various sorts of drugs were put into these cigarettes but they had drugs called asthma cigarettes. Again, I doubt that it was very helpful for asthma patients, but that's what they had, but. The more interesting story I think is the story of metre dose inhalers.
If anyone on this call uses a metre dose inhaler or has a friend or a relative or family member that has asthma and uses these, they were developed in 1957, but this is the interesting story. 1955, there was a 13 year old girl named Susie Mason. She had asthma and she asked her dad if there wasn't an easier way to treat the disease like hairspray.
Now the reasons why she was asking about hairspray was that her father George Mason was the president of Riker Labs. Riker Labs was owned by Rexall Drugs, which until about 30 years ago was one of the primary pharmacy chains, at least in the states. They were also one of the first makers of hairspray.
So George, dad of Susie, assigned his lead chemist to develop a pressurised device which 3 years later became the metre dose inhaler, and that was the thing that we're using now. The basic parts of that were developed in 1956 because Suzie Mason asked her dad to make one. And for context, the current sales of inhalers are about $36 billion globally.
And 2000 people around the world are using one every second, including every second that I'm talking. So that's the history that I thought was pretty cool and I didn't actually know all of that. In terms of the history of aerosol drug delivery, so we know in the top you can see delivery of a metre dose inhaler through a space which we'll talk about to a young girl, and that's been happening since the 60s and if you look on the right side, the same exact system is being used for a cat.
We've been using that since 1990. The theory behind the use. Well, think about if a dog or a cat has a respiratory arrest and they have an endotracheal tube.
One of the ways we're taught to give drugs is to instil it through the endotracheal tube because the respiratory mucosa is lined with so many blood vessels that it's a beautiful path for absorption of drugs, and that's liquid. If you vaporise the liquid, so it's an aerosol or a nebulizer sized droplet, it gets absorbed even more quickly. And think of the respiratory tree as the port of entry into the lungs.
The tree is basically plumbing. It's just a tubing system that brings air from the environment into the lung where oxygen exchange occurs. So the idea of having drugs that are absorbed through the respiratory mucosa isn't actually very new.
Why the specific drug fluticasone? I have no stock in fluticasone. I don't know who makes it anymore.
Company's been sold a couple of times, but there's a reason why we've always used this drug which has different names in different companies. So the generic is fluticasone in the states it's called Flovent. Well, remember, historically, the way we treated airway inflammation was injectable in oral corticosteroids, and I'm old enough to remember when we used to give deparmental injections and it would last for 2 to 4 weeks.
The problem, of course, and I think we're all aware of this in both dogs and cats, is the potential for behavioural changes, polydipsia, polyuria, increased appetite, skin and urinary tract infections, and even insulin resistance, which more in the cat than a dog, it's sort of a a diabetic-like state which often can be reversed when you stop the systemic steroids, but still it's a pretty nasty side effect to have. So the idea of using inhaled steroids is basically that they're not absorbed. There are no systemic side effects, and whenever someone says there are no side effects, you have to go, well, there's gotta be some.
Well, I've been doing this since 1992. There really are no systemic side effects to these drugs, and there have been lots of studies done to determine whether this stuff actually gets absorbed or not. So it's the safest kind of steroid you're ever gonna use in a dog or a cat.
Why this particular steroid, well, I'm listing just 5 on the slide. There are more, but flu fluticasone in the states is called Flovent. There are 3 reasons why Flovent is chosen and mostly in people and in animals.
The first is that if you're looking at how strong these drugs are, there's a standard called the McKenzie skin blanching test, and that's not terribly important. But the point is of the drugs that I listed, Flovent is absolutely the most potent inhaled steroid that's available, so that's the first good reason to use that drug. The second is to think, well, how often do I need to give this drug?
How long does it last? And that's measured by receptor binding half life or how long does it take for the drug to fall off about 50% of its potency. And again, as you can see on this slide of the 5 inhaled steroids, Flovent lasts the longest, so generally it needs to be given twice a day and we'll get into that under treatment.
So it's the most potent and it lasts the longest. The third, and this is the thing that's interesting, when you or I or a dog or a cat inhales a drug, whether it's a steroid or a bronchodilator, most of it actually impacts on the back of your throat and you swallow it. So while the stuff that gets absorbed into the respiratory tract is 100% bioavailable, the stuff that gets swallowed can get absorbed by the gastric mucosa.
If that happens, that's systemic absorption, and now you're talking about the potential for actual steroid ingestion into the bloodstream. And so when you look at the steroids that are available by inhalation, if it gets absorbed through the gastric mucosa, only 1% of that drug actually goes into the bloodstream. And it has to do with lipid solubility and alkalinity versus acidity and molecular size.
So it's the most potent. It lasts the longest and it's the least likely to actually get into the bloodstream even if it's swallowed, which is a pretty common phenomenon. When you look at the bronchodilators, there's nothing special about this except that albuterol, which is the trade name of Proventil or Ventolin in the states, is most beta 2 selective, which means if you inhale it, it's least likely to beat on the heart or cause tachycardia or increase oxygen consumption of the cardiac tissue.
It's most likely just to cause bronchodilation. Now just as a comment before we get into a little more, there was a paper years ago if anybody is interested in this or anybody has asthma you might have read about this there were some warnings that inhaled bronchodilators could lead to sudden death in people and this was an article published in the New England Journal of Medicine. Jeffrey Drazen was the head of pulmonary medicine at Harvard Medical School.
It was a very, very rare side effect, but it was still worth noting. And about 2 years after that, one of the folks in our profession, Car Ronero, talked about the same kind of theoretical complication in cats. That's the only paper that ever tried to prove that in cats and dogs, and in fact, I can't tell you anecdotally, having treated more than 300 cats with asthma and about 150 dogs with chronic bronchitis, I have never seen sudden death occur, so I think it's a pretty rare and unusual side effect.
Why do we use it? Who do we use it for? Well, for dogs, we're talking about chronic bronchitis, which is either idiopathic or eosinophilic, and I'll mention both of those in a minute.
For cats, chronic bronchitis or asthma, and there actually are differences between the two, which I'll mention briefly. And for both the dog and the cat, chronic lymphocytic plasmacytic rhinitis is another great indication to use inhaled steroids. So as we talk about each of these diseases in brief, we can explain why this is helpful.
Before I move on, I think it's fair to say, because this is a talk about inhaled medications, I only briefly talk about the diagnosis of these diseases. I'm really mostly talking about the inhaled medication aspect of the disease and I hope that's OK. When we talk about chronic bronchitis.
Commonly, the term COPD is used and let's make a point that it's actually a very inaccurate term, and the reason is COPD is typically referring to people who smoke cigarettes, who have chronic bronchitis and emphysema. Now, emphysema is actually the reason why people with COPD have trouble breathing because emphysema is a disease of the lung. And it causes problems with oxygen exchange, but it exclusively is a disease of smoking.
You can't get emphysema unless you have a very rare deficiency of an enzyme called alpha one antitrypsin. So basically, COPD in people that includes emphysema is not a disease we see in dogs and cats, even when they live in homes where people smoke cigarettes. So COPD doesn't really have the same connotations in animals that it does in people.
So COPD really for dogs is chronic bronchitis. The definition of chronic bronchitis in dogs is really pretty straightforward. It's the disease that causes a chronic daily cough in dogs when other causes of cough are ruled out.
Now that sounds really vague, but in most clinical situations, it's actually pretty straightforward. If you have a dog with a history of a chronic daily cough. You have a physical exam that shows a pretty normal dog except perhaps crackles when you're listening on the lung, and you have radiographs of the chest that have a bronchial pattern.
Unless there's another significant thing that you're missing that isn't showing up on an X-ray, you can back into a diagnosis of chronic bronchitis for that reason. Now that is, you know, worst case scenario, of course, but that's an example of chronic bronchitis in a dog. If you look on the right side of the screen, you can see a lot of air in the stomach cause dogs have air hunger and as they breathe harder, they swallow some air.
The diaphragm is relatively flat, so the crisp of the diaphragm is out by T13, but mostly you're seeing a very heavy bronchial pattern with large dilated airways. There's another form of bronchitis that they call eosinophilic bronchneumopathy, and that was demonstrated by colleagues in Belgium some years ago and it specifically talks about a specific kind of bronchitis which is not chronic and daily but it's episodic and it may occur only in the spring or the fall. When it happens, it's a nasty form of bronchitis because these dogs are kind of sick as opposed to most dogs with bronchitis that are not, and you find it in the snow dogs, the huskies, the malamutes, etc.
And those dogs, unlike dogs with chronic bronchitis or is idiopathic, these dogs are dys can have a sudden onset. On the left you can see DV in the lateral of a dog with eosinophilic bronchitis and the hours are pointing out different aspects of a bronchial pattern. On the right is the same dog.
About a month after steroid administration showing resolution of a great many of the characteristic markings, but what makes this different again is when you go into the airways, you can see this green really goopy mucus, which is very characteristic of a massive amount of Eosinophils that have just died, and instead of having mucus that's white or grey, if anyone does this for a living and you do bronchoscopy for a living. You note that this green mucus is very characteristic for eosinophils. And actually, if you do the cytology, as you can see on this slide, it's just an enormous raft of osinophils.
The reason I bring this up is that in dogs that have acute cough and you find it's not infectious, especially if they're the snow dogs, malamutes, huskies, these dogs are sicker than most dogs with bronchitis, and they respond dramatically to steroids within 24 to 48 hours, the symptoms are completely gone. So it's a specific form of bronchitis that it's at least worth being aware of. As was another disease, of course we see in cats, this is not a dog disease.
This is a disease exclusive to cats and people, cats and people now horses get a form of reactive airway disease which we call heaves, but it's not allergic airway disease the way cats and people have, and it's not spontaneous. Now for purposes of this talk, I won't go any farther into that, but allergic asthma spontaneous. Asthma that comes and goes is unique on the planet to the feline species and the human species.
If you or I have suspected asthma, what happens is we have a cough and it's raspy and we get short of breath and it comes and goes, and we see our physician and they use this thing. It's an in-office spirometer. It basically, basically ask us to take a deep breath and then blow out as hard as we can, and this thing can tell if you're having trouble moving air out and it's pretty characteristic for an asthmatic patient.
So typically, after X-rays in an in-house machine like this that you blow into, there is no other diagnostic test that's used for asthma because in fact, they use inhaled steroids or oral steroids and if you get better really, really quickly, it's diagnosis by response to therapy. Now we don't have a spirometer in in cats, but we do have other ways of diagnosing the disease. If the cat comes to us with a history of cough or wheeze, or respiratory distress that may be every day or it may be intermittent.
And put in the back of your mind that Siamese and Siamese like breeds, Siamese, Burmese, Himalayan are overrepresented. These guys don't have any other cause of their symptom. And if you think about it, there is no other disease where you're spontaneously, intermittently cough and wheeze, and then you're fine for weeks and then you're symptomatic and then you're fine for weeks.
That Intermittent nature of the disease is what the definition really of asthma is now it can also cause a daily cough, but typically this is something that comes and goes. The radiographs may be normal or they'll be consistent with bronchial disease if they're not then. It's probably another cause of the symptoms and you need to look elsewhere.
And again, diagnosis by response to therapy, these guys respond dramatically to high dose steroids and after a couple of days, the symptoms are pretty gone and you have a pretty good sense that you're dealing in fact with asthma. Characteristic asthmatic cat on the left you see the lateral, the other side, you see the DV and again you can see an awful lot of air in the gastrointestinal tract because these guys have what's called air hunger. They're breathing really hard and they're swallowing a lot of air.
The second thing is to realise that the lung is really hyperinflated. The crisp of the diaphragm one more time is out by T13L1, and the diaphragm is flat. And lastly, you can see a very heavy bronchial pattern with lots of doughnuts and tramlines, and that's basically what most people use to diagnose asthma.
You don't need to do bronchoscopy or advanced imaging. The third condition to consider for inhaled steroids in dogs and cats is chronic lymphocytic plasmocytic rhinitis. No, I apologise for the pictures.
Snot is snot, that's what we do for a living, so I figured it's OK to show this audience dogs and cats are snot coming out of their nose. But when you have dogs and cats with chronic nasal discharge and you've ruled out things like tumours, foreign bodies, it's not acute, it's a chronic problem, but when you've ruled out other. Things aspergillosis in the dog, you back into the diagnosis of lymphocytic plasmocytic rhinitis, which is basically an inflammatory non-infectious disease.
It's sort of like inflammatory bowel disease, but it's in the nose, so it's inflammatory nose disease for lack of a better way of thinking of it, but it's inflammatory disease, it's not infectious. Now for lymphocytic plasma cytic rhinitis, I bring it up because if you treat that, and it's commonly treated this way as an infection and you give antibiotics, it clears up the bacterial component of the problem for a short period of time and then it comes back. But by not treating the underlying inflammation, you let the inflammation continue and you get destructive rhinitis.
And on the left you can see. What looks like a normal nares endoscopically, and the two slides on the right show what happens to normal narries after chronic inflammation is left untreated, you lose the epithelium, some turbinate structure, etc. And then you do have a chronic problem.
And what are the trooper principles for chronic nasal disease? Well, it's not just steroids, you have to treat the secondary bacterial involvement because there is a bacterial component to lymphocytic plasma cytic rhinitis. Once you get rid of the bacterial component, you have to treat all the snot that's in there cause an inhaled steroid can't get into the respiratory mucosa if there's snot.
So you can do nasal flushing and more easily, you actually can use a decongestant and I'll show you the picture of that on the next slide. But once you've gotten rid of the bacterial component and you've gotten the mucus out of the nasal cavity, the underlying problem which is inflammatory, is very beautifully treated by inhaled corticosteroids. Now it turns out the infectious component of this is both aerobic and anaerobic, and that was demonstrated by Lynnell Johnson and others at Davis years ago, but it showed both aerobes and anaerobes are part of this component of lymphocytic plasmacytic rhinitis, and you have to take that into account when you're taking charge of the antibiotic component.
I happen to choose Xeniquin, marblefloxacin, and clindamycin. Because it gets the aerobes and the anaerobes, and marbfloxacin is a tad more effective at certain streps and pseudomonas that occurs with chronic LP rhinitis compared to other fluoroquinolones. Clindamycin, of course, gets the anaerobes.
F lo x ac in is a more common drug now, a flu fluoroquinolone that covers both aerobes and anaerobes, but it's just to make the point that you have to get rid of the stuff in the nose before an inhaled steroid can touch the respiratory mucosa in the nose to be effective. And this is the decongestant. Little nose is is the trade name.
It's a quarter or an 8 strength and that phenylephrine, and the idea is just to put a drop in their nostril once or twice a day for a couple of days and then acts just like you or I, it'll be a decongestant, it'll shrink up the mucosa, so it's not leaking, and then when you use the inhaled steroid, it can actually touch the respiratory mucosa. And once that happens again, is the inhaled steroid, which we'll now talk about in just a moment in more detail. How do you administer this stuff well.
Metre dose inhalers can work for adults cause we can time. Spraying and then inhaling, but that doesn't work for infants and children, and it doesn't work for dogs and cats. So there is something called a spacer which is the tube, and you can see it below both for a child and for a cat.
When you spray the metre dose inhaler drug into the spacer and the mask is on the patient, timing isn't necessary whenever the cat or the girl, the young child breathes in. The drug will be available and it synchronises breathing much easier so you, you actually can make this an effective form of drug even though the muted dose inhaler by itself isn't effective. When you place that tube or a spacer on it, it becomes a very effective delivery device.
Now the technique in this comes from the Trudell Corporation and Breathe Easy, so thank you both companies for supplying this. The metre dose inhaler has a cap. You take it off.
You shake the inhaler a couple of times and put it in the end of the aerosol chamber, in this case, the aeroca spacer. Once it's in there, you put the mask onto the patient's face, both dogs and cats, and then you spray the metre dose inhaler. And when you do that, you allow the dog or cat to breathe at least 7 times, and that'll get out all the medicine that was put into the spacer.
And this spacer actually has a little flap valve that moves back and forth, so every time the dog or cat breathes, you can see the breath, and after 6 or 7 or 8 breaths, you're done for that administration. That doesn't matter what space they use, it actually does. The biggest complication of using these drugs turns out to be for many people cost.
It's very easy to give these drugs to dogs, a little more complicated than cats, but I'll show you some data on the effect of that in a second, but the biggest deal is cost, so the more effective the spacer is in getting the drug into the patient, the cheaper it's gonna be in the long run. And this slide simply shows without getting too complicated, at a tidal volume of 25 ccs you can see that on the bottom, it is about the title volume of an average sized cat. The arrow cat will allow, it's in yellow, about 20 mcg of drug to actually go into the cat of the 110, which is the normal dose that comes out of a metre dose inhaler, and that's much more than other chambers that are made for.
So the spacer, the Aerocat is actually the most effective delivery system and it has to do with anti-static properties, etc. But that's why we use it. It's a very effective delivery device and it was specifically made for dogs and for cats.
Now does it actually work? This is a paper by Rhonda Schulman who is at the University of Illinois that basically took fluticasone and tagged it to something called TCDTPA. The name isn't important, but when they inhale the drug with that thing, it can be found with a gamma counter.
And if you look at the lateral film on the left or the DV on the right, you see a lot of the drug is deposited in the head and then down towards the lungs, but there's no question the drug gets very well absorbed into the respiratory tract and down into the lung, and there was a very nice study demonstrating that in cats. Well, in the internal medicine journal in 2017, they demonstrated the exact same efficacy for dogs, so they raised a label for ticosone, they measured it with a gamma counter, and they found that this form of delivery is actually very effective for putting the drugs into the part of the airway that they want to put it. Is it effective?
Well, there's a paper from the Canadian Journal of Veterinary Research that came out not too long ago, and it was treatment of naturally occurring asthma with inhaled fluticasone or oral prednisone, and it was a pilot study, so this isn't a completed study. It's not double blind and placebo controlled, and it's not powered correctly, but it is an abstract to look at whether or not cats with asthma are equally treated effectively with oral drugs or inhaled drugs. And Elizabeth Rosanski at Tufts was one of the authors that I appreciate being part of this and basically, and remember we're talking about real patients now that are being anaesthetized, they're being bronchoscoped, bronchola Lavage is performed, pulmonary function tests are performed, so it's not easy to get lots and lots of patients into the study, but they had 9.
All cats had asthma based on clinical signs, chest X-rays. Bronchovila lavage its found lots large numbers of eosinophils. They had pulmonary function tests, and they also had fructosamine tests to make sure they weren't causing insulin dependence.
All cats got oral glucocorticides for 7 days, and then 4 cats continued with oral glucocorticides for another 7 weeks for a total of 8 weeks. 5 cats continued with inhaled fluticasone for 7 weeks for a total of 8 weeks. And after 8 weeks, all cats, all 9 cats were clinically without signs, which was pretty cool.
They repeated all of these tests, and for both groups, the number of Eosinophils and bronchovila lavage fluid had gone down in an equivalent fashion. Interestingly, there were no changes in chest radiographs, which reminds us what an X-ray looks like is not necessarily what a patient looks like. So I always remind myself I'm not treating X-rays, I'm treating patients.
And finally, the fructosey never changed, so whether it was oral glucocorticoids or the inhaled insulin resistance didn't seem to be a problem with these drugs at these doses. Another paper, in the BSAVA a couple of years ago that demonstrated in 13 dogs with eosinophilic bronchitis, which is a more serious form of bronchitis that we talked about, 3 of those and 10 with chronic bronchitis that are standard, 9 of the 13 dogs with bronchitis using inhaled steroids alone had a partial to complete resolution of signs, meaning the cough stopped significantly that the owners were very happy with that outcome. Four of the 13 dogs needed some oral prednisone in addition to the inhaled steroid, but even then that's a real advantage because you don't have to use as much systemic steroid and you don't have to use it as often.
So that's a win for dogs as well. I published or I presented at ACVM some years ago, 300 cases that I had put together over about 5 years when I was in practise in Chicago, and out of 300 cases, about 10 to 15% of cats you really can't train to use in my experience. The rest of the side effects were pretty trivial.
You get some ocular irritation because there's some drug that slips outside of the mask and you can wash it down with a washcloth. 2% of cats had some hair loss around periocular region. Some percentage of coughs of cats coughed when they first started using this because remember they were actively coughing cause they had asthma and that resolved very quickly.
In people, there are issues that are related to growth retardation and thrush, which is candidiasis in the back of the throat, and theoretically, if they already have a viral infection, if you use it like influenza, if you use an inhaled steroid, does it make the viral infection worse? And it turns out none of those things are actually a problem for our patients. Our dogs and cats don't have growth retardation.
Our dogs and cats don't have candidiasis. And even with active herpes infection in cats, using inhaled steroids is very effective and doesn't exacerbate the presence of the disease. And with dogs with influenza, it also doesn't exacerbate the viral infection itself.
So it's a pretty safe drug to use. This was just published in BSA VA. It was accepted.
I don't think it's actually published yet in 2021, and this was done by Shea Sartori at True Del Medical and Elizabeth Rosanski, at Tufts, and they looked at 22 dogs and 22 cats, and the question was, will cats and dogs accept having this mask and chamber combination? I've been using it since 1992, but other than the statement that I made it, . The Internal Medicine Journal a couple of years ago, I had never published anything, so I really am appreciative of Shay and Doctor Her and Elizabeth for publishing this.
They looked at 22 dogs and 22 cats, and they asked owners to rate acceptance based one would be not tolerated at all up to 5 which would be perfect compliance, and what they found is in 30 days all the dogs were compliant. And that's actually my experience. Many very few dogs are really concerned about having a mask, which is kind of like the oxygen mask you put on if you're in a treatment area, but when you put it on their face, very few dogs are objecting, and the few that do, if you put a little.
Cream cheese or a little peanut butter on the inside of the mask, they're happy with the mask on their face and their tongue is licking all the stuff off, so that's easy. So all dogs were compliant in 22 cases and that's absolutely true in my experience in the cats, two are non-compliant. And of the 20 that were left, 18 were compliant within 30 days.
Now the median time to compliance rates from 6 to 2 to 19 days, but within a month, virtually all the cats and always all the dogs are compliant to the system. So while it sounds like this is gonna be a hassle if you've never done it. And it sounds like difficult.
There are lots and lots of movies on YouTube with owners of cats and dogs using inhaled medications that demonstrate exactly how to do it, and it turns out it is a pretty simple way to deal with it, although if you've never done it before, it sounds like, oh, I don't know, once you've used it, it turns out to be pretty simple methodology, and I appreciate Shay and Doctor Rozanski for publishing this. What's the cost? In the states.
At the very least, a 1 metre dose inhaler that puffs out 110 mcg and the next slide we'll talk about treatment and dosing. Would puff out 2 puffs a day and after. 30 days that'd be 60 puffs.
So if the metre dose inhaler is 120 puffs, basically, a metre dose inhaler would last for 2 months. If you go to the most of the drugstores in the United States, that metre dose inhaler is more than $120 that RXDirect.com in the states has it for $120 but even then it's $60 a month.
But as you can see in Canada, Canadian Cloud Pharmacy will sell that metre dose inhaler for $35 US. World Pharmacy $35 there's a. Count code in Australia, this pharmacy will supply a metre dose inhaler at $25 US and remember the canister lasts for 2 months.
So if you divide these in half, $35 US divided by 2 is $17 or $18 a month. So the cost isn't really the factor that we originally were concerned about when we first started using this drug and the drug cost was phenomenal. If you use these sources, it really becomes a much less expensive drug to use.
So what are the treatment protocols? Well, Basically, I still use oral prednisone to start my treatment for asthmatic cats, chronic bronchitis in dogs and cats, and lymphocytic plasmacytic rhinitis in dogs and cats, and there are two reasons for that. Number 1, it's really easy and really cheap also, but number 2, these diseases are sometimes assumed and you're making your best guess as to that being the diagnosis cause lymphocytic plasmacytic rhinitis, for example, requires anaesthesia and a biopsy for confirmation.
So we make these diagnosis clinically and in response to therapy. The best way to test response to therapy is to use a very high dose of an oral glucocorticide for just 2 days. And the idea is this, if you have a migraine headache and you take a baby aspirin, you're probably not gonna get better, but it doesn't mean aspirin isn't the right therapy.
But if you take a whole lot of aspirin, the migraine may go away. So the proof of concept that the diagnosis is in response to therapy requires a high dose of prednisone for a very short number of days, and that's why I start with oral prednisone. And a milligramme per kilogramme, divided twice a day is usually enough for most dogs and cats to get that required response because remember this is not an immunosuppressive dose, this is an anti-inflammatory dose, and for bronchitis, asthma, and LP rhinitis, they're really responsive to steroids.
So I start at a high dose and within 48 hours if the patient is responding very well, I start weaning to the lowest dose I can. If I can get to a very low dose that I can give every other day and the patient is asymptomatic in terms of the drug, that may be a reasonable way to go. But most of the time, the amount of prednisone systemically you need to control, to control these diseases is more than the patient will tolerate in terms of polyuria, polydipsia, changes in hunger, etc.
So that's what most of the time these guys wind up doing beautifully on inhaled steroids. So if weaning causes a resumption of symptoms. Let's walk through this one step at a time.
If you assume a canister is labelled at 110 mcg of Flovent in the UK, I think it's called flexitide, and it may be labelled as 125 mcg of Flovent, it's the exact same dose. If we assume that one puff of the 110 mcg metre dose inhaler is equal to 5 milligrammes of prednisolone, you can start to get a sense of the dosing. Let me go to the bottom of the slide right away.
The dose of this drug is not dependent on patient weight. It's not the same thing as it's milligrammes per kilogramme, so you're giving much more drug to a mass than you give to a poodle. It doesn't quite work that way.
You're really talking about the cross-sectional area of the nasal cavity, and even if I look at my pug or my German Shepherd. The nose of the German shepherd is a whole lot bigger, but if you go to the second line on the slide, Flovent at 220 mcg, 2 puffs twice a day, is an enormous dose of inhaled steroid to prove that it will continue to work. So let's work through that.
If a canister is 110 mcg. If you puff it twice into the spacer and they breathe that, they're getting 220 mcg. If you do that in the morning and the evening, that's the maximum dose of Flovent that you'll ever need.
More doesn't give a better clinical result, it's just more expensive. So one puff of the 110, I'm sorry, two puffs of the 110 mcg given twice a day, it's about as high as you want to go. Now Flovent takes 7 to 10 days for a full effect.
There's no acute effect to this. So if you have a dog or a cat with bronchitis or asthma or with lymphocytic plasmocytic rhinitis, while you're using the inhaled steroid, you want to start weaning off the oral prednisone over the 7 to 10 day period so that by the time they're off the oral prednisone, they're on the inhaled steroid with full effect. Now remember to inhale steroids are not more effective than systemic steroids.
They're just safer. They're not absorbed, and that's the beauty of these steroids. So it's not even just if they have symptoms of steroids, if the patient's diabetic, if the patient has hypertrophic cardiomyopathy, the patient is Addisonian, if there are other comorbidities, hypertension, it really makes using oral steroids chronically really not ideal.
In these cases too, using the inhaled steroid is a beautiful way to go. Once the patient is actually on the inhaled steroid, most dogs and cats, and again we're talking about a 5 pound cat and a 100 pound German Shepherd, do pretty well at 110 mcg, which is one puff of the spacer given twice a day, and the irony is it's really, and I'm not saying physicians do better than we do, but the parallel use of the drug is in people. Kids can get the same dose that adults get of inhaled steroid because you can't overdose them.
You can't make them sick if you give him too much. The only problem with giving too much drug is it costs more, and I'm not negating the importance of that, but you want to use the highest dose you can in the beginning to make sure you're getting the clinical effect and then you start to try to wean down. And lots of dogs and cats with these diseases can do really well at one puff of 110 mcg given twice a day.
And the indication for albuterol or Ventolin, also called Proventil, is only for cats, and this is the reason. Dogs don't bronchoconstrict. Dogs don't get asthma.
Dogs don't need or respond to bronchodilators. That's a little bit of inflammatory response for a lot of people in this seminar and others because we're taught in school to use things like theoplin and dogs with all kinds of problems. We studied bronchodilation and bronchoconstriction in dogs using pulmonary function tests, and we published this in the internal medicine journal years ago.
Dogs don't clinically bronchoconstrict. Excuse me one second. I apologise.
And so, although you may be taught that. And if your clinical experience is that giving bronchodilect helps dogs. You should absolutely use it, but in my experience in the studies we did, they don't bronchoconstrict, but cats with asthma do.
If cats don't have symptoms more than every once in a while. The owners can use the inhaled albuterol, it's a metre dose inhaler through a spacer, just like they use the steroid. As a sole treatment.
So if the cat only coughs once a week, they don't really need daily steroids and they can use the albuterol as needed. If they're on inhaled steroids and they're still having breakthrough coughing, they can still use the albuterol even every day if they need to for coughing, wheezing, increased respiratory rate, or efforts. As you might have guessed by now, I'm asthmatic.
I'm on inhaled steroids and every once in a while, I need to take albuterol as well and that's the advantage that while the inhaled steroid does cause a little bit of tachycardia in dogs and cats and people, it's still a pretty safe drug. What are reasonable expectations? Well, people with asthma or bronchitis still cough.
People with asthma and bronchitis still wheeze. People with asthma and bronchitis still get hospitalised. People with asthma and bronchitis still need oral steroids.
So this isn't a magic metre dose inhaler. Let's remind ourselves they're not better than systemic steroids, they're just safer. They're equally effective in most cases, but they don't get absorbed, so you don't have to worry about the side effects.
They just take a little longer to work. But people with the best medical care in the world sometimes still need oral steroids in addition to inhale steroids, depending on how bad their condition is and sometimes they're out of control and need to be hospitalised anyway. So these diseases of bronchitis, asthma, and lymphocytic plasmacytic rhinitis are treatable diseases.
They're not curable diseases. That's really the best way to look at it, I think. I want to thank the webinar Virtual Congress 2021.
I want to thank Breathe EEZ for sponsoring this and I wanna thank Shea Sartori of Trude Trudell Medical for being so enormously helpful in getting this through cause remember Trudell started this with me in the early 90s. Trudell makes spaces for people. This got started in the early 90s for cats and dogs because the people at Trudell decided it'd be worth it to start helping dogs and cats rather than just people and that's where it got started.
So thank you, webinar vet. Thank you, Breathe Easy, and thank you Shay. And this nice lady on the left named Helen, is 98 years old and her advice for the younger generation.
Be nice to everybody. So thank you all very, very much for your attention today. Thanks, Phil, and what great advice at the end, we, the world would be a better place if we all did that, wouldn't it?
I believe that's true. Thank you so much. That was splendid and and really interesting, as I say, I'm.
I've learned a lot from, from the whole webinar, so thank you so much. Obviously people can ask questions, obviously thanking also Breathe Easy for sponsoring this session. If you'd like to also, just so we can see where everybody's listening in from.
Do go into the chat box and just tell us where you're listening in from. It's always interesting, isn't it, Phil, to see where people are, are coming from. We've got Lottie from Belgium.
And Jenny from Virginia, USA, so not too far away for you. Vanuatu, Vanuatu, I think that's the first time. That's fantastic.
Thank you so much for coming in to . To see the weather now, let's see, Scotland, Wexford in Ireland, Vienna, Austria, France. Bloomington.
Portugal, Berkshire in the UK. Iran, Turkey, Costa Rica, Portugal, Cape Town, Zambia, Israel. So people listening in from all over.
So thank you so much, Phil, for helping us all just to get that bit better because this is a, a, a really important area and having that extra. Possibility to treat with inhaled medication is, is fantastic. If people do have questions, please do put them in the question and answer box, and I will pass those on to, to Phil.
We're also going to have a go and see if it works, and actually, trying our vet exhibition where we can go in and chat after as well, . So let me see questions. Is it acceptable to give a dose of inhaler into the spacer and then take to the pet, so the hiss does not occur so close to the pet's face?
Does, does that hiss seem to upset them, Phil? Oh, what a wonderful question. I, I was gonna get to that and I didn't have a chance.
One of the things that the Trudell company did was actually study that. If you put the medication into the spacer. You can wait as long as 5 seconds before you put the mask onto the cat.
You lose about half of the drug delivery. So what it means is you still can do that, but you'd need to use twice as much drug. And the reason for this question, of course, is that sometimes when the mask is on the Or the dog, they're OK until you spray the drug and they get frightened by the spray.
If that happens, you can spray first, wait 5 seconds, put the mask on the cat or the dog, and just realise you have to double the dose, but it's a great question and thank you for asking it. Thanks Hillary and Phil. Lottie has a question in Belgium and maybe in other countries as well.
Flicks are ide, 125 mcg isn't available anymore. We only have 250 mcg and 50 mcg. Since 220 BID 2 puffs is the max, would you recommend 251 puff BI start?
It's the same dose, isn't it? Yeah, 220 and 250 are the same dose, so just labelled a little differently. And you know, I have to be honest, there's no.
Data to prove that one dose is better than another, and in fact, there's no data to prove it in most people and children. This is an a trial by error, and the reason why I go to the highest dose, so 250 twice a day, is cause it's the greatest chance to see if a high dose will be effective, like giving lots of aspirin for a migraine rather than just a baby aspirin. Once you've proved the concept that your patient is stable.
On the inhaled drug at that dose, then you can start trying to lower the dose and see if they remain stable. And it's really just a question of cost. If this drug was really inexpensive, giving the highest dose twice a day would never be a problem for the patient cause it doesn't get absorbed.
So yes, 250 twice a day would be perfectly acceptable way to start. That's great, thank you, Phil. We've got another question.
Hillary is coming up with a question, so we'll let Hillary ask another one. If you are treating a dog with inhaled steroids and they develop an infection, do you stop the inhaled steroids or lower the dose or continue with the same dose? So, this is a great question.
Do you, do you stop or change the dose of an inhaled steroid if they get an infection? Dogs with chronic bronchitis and cats and dogs with. Cats with asthma, it, it's typically not an infectious disease and that's one of the reasons I started the conversation by saying COPD in people is not the same as COPD in the dog because COPD in people is caused by cigarette smoke and it alters secretory IGA and cilia and respiratory defences.
So people with chronic bronchitis get infections. Dogs and cats really don't, and that's been studied a lot. People have done bronchoscopy, cultures and sensitivities.
These guys don't get infections, but let's say a dog with bronchitis gets cattle cough, and that's really a question. What's really cool is that the inhaled steroid does not affect viral infection or even bacterial infection because it doesn't get systemically absorbed and the amount of drugs that's in the respiratory mucosa that decreases inflammation doesn't affect the systemic ability to fight off the infection. Actually, children with children with bronchiolitis obliterin, it's a really nasty disease in infants and young kids.
It's a viral infection because part of that involves bronchial constriction and active part of the therapy during the active viral infection is to inhale steroids. So it's an unusual scenario, but you don't have to stop the inhaled drug if you're starting the antibiotic. That's great though that that's really, really good, .
Elizabeth is saying thank you from Germany. The the problem with, with, webinars is you don't hear the tumultuous applause at the end of the webinar, but, people are really pleased with it. They've said, Lossie said thanks a lot of information in a short space of time, excellent talk, all made simple and clear, and we've got .
Moshin from Nairobi, Kenya saying thank you for the great talk. And Sue, many thanks, excellent talk so.