Good evening, everyone. I'm very pleased to be here tonight to discuss to you about maintenance anti-epileptic treatment. Epilepsy is one of the most common neurological presentation in practise, and is, is something that can sometimes be quite difficult, to manage.
What we're going to discuss tonight is when should we start antiepileptic drug. Why should we start? What are the evidence?
What drugs should we use? And how should we use this medication? What kind of monitoring should we put in place?
And in the second part of this talk, we'll discuss what to do when things are not doing well. Discussing, you know, refractory epilepsy and how to manage that and side effect of medication. So I hope that this presentation will be useful in terms of how to handle this epileptic cat and dog.
Epileptic seizures, in case you've never seen one, the most common form is the generalizedtonicoclonic seizures where you can see on this video on boxer, in dogs, more than 90% will have this generalised tonicoclonic seizures and more rarely will have partial seizures. In cat, as we've seen in the previous presentation. It's probably fifty-fifty between having generalised and partial seizures.
But when you have an epileptic seizures, it means that there is a forebrain disorder and the underlying cause can be found in the brain, which we define as intracranial cause or outside of the brain, which is the extracranial causes. Intracranial causes are divided into functional disorder. Which is referred as idiopathic epilepsy, which is the most common cause of epileptic seizures in human and in dogs, but also in cats.
And it's simply an abnormal wiring in the brain that predisposes you to have epileptic seizures, something you're born with and something you will live with for the rest of your life and only exceptionally die of. The other inconal cause would be when there is a structural disease triggering the seizures, and we in that case, talk about symptomatic epilepsy. The third cause of epileptic seizures are extracranial cause.
They come into the re the category of reactive epileptic seizures on the basis that the brain is totally normal, totally healthy, but it's reacting to something abnormal in the blood and this something could be a metabolic disturbance or toxicity. Idiopathic epilepsy, as I say, is the most common cause of epileptic seizures in cat and in dogs, but also in humans it's a functional disorder. But ultimately this abnormal worrying is causing an imbalance between excitation and inhibition in the brain.
Which stop the brain being able to stop a seizures occurring. Potentially we could, we could all have a seizures given the right circumstances and you know, for example, that video games can trigger a fit, but they can trigger a fit if you are prone to have an epileptic fit. And if you are prone, then the balance will, will, will fall into too much excitation or not enough inhibition and then you're going to have an epileptic seizures.
The diagnosis of epileptic or idiopathic epilepsy is made by exclusion of overcos. You expect to be totally normal in between, so your neurological examination will be normal, however, shortly after a fit, the animal may be transiently abnormal for a few minutes to a few hours. That's what we call the post-cyclal phase.
And in dogs, at least, idiopathic epilepsy tends to start between the age of 6 months to 6 years. And more often cause generalised seizures, at least in dogs. As I say, epileptic seizures refer to a forebrain disorder.
So in terms of neuro localization, that's where you need to focus. And when you need to evaluate a dog with epileptic seizures, then I'm going to do a targeted neurological examination, focusing on forebrain function, asking the owner about the behaviour of the dog, any abnormal gait, like circling to one side. Is the animal have normal vision which I will assess with the menace response?
Is he also normal response nasal stimulation which again involves the forebrain, and I will finally test the, the, the post reaction doing poor positioning and hopping. And this way I can test the forebrain function and determine if the dog is normal, which you will expect withidopathic epilepsy. Or potentially abnormal, which you may see, for example, with structural brain disease.
Ultimately, whatever the underlying cause, there is an imbalance between excitation and inhibition in the brain, not enough inhibition, and that's usually mediated by gaba neurotransmission or too much excitation, which is mediated by glutamate neurotransmission. Diving into the treatment. We're going to focus primarily on the treatment of idiopathic epilepsy.
If there is an underlying cause, then it goes without saying that the way to treat the seizures is, if possible, treating the cause, sometimes that would be enough, sometime you will have. In addition to give anti-epileptic drugs, but with idiopathic epilepsy, the aim of the treatment is to control the seizures with minimum side effects. So to find the right balance between the positive effect and the negative effect of the drug.
But you need to be very specific with the other. What do we mean by control, and it's important to set the expectation from the, the onset. Controlling in an ideal world may be having no seizures, which you may be able to achieve.
However, in most cases, controlling will imply reducing the frequency and the intensity to an acceptable level. Difficult, very subjective, what would be acceptable for one pet owner may not acceptable for another one. But I will say that if you can have 1 fit a month or 1 fit every 6 weeks or 6 to 8 weeks, will be a fairly reasonable expectation.
When should you start antiepileptic medication? They are school of thought, and there are situations where there is no doubt. If the animal is having status epilepticus or cluster seizures, and if there is no metabolic or toxic cause for that, I will definitely start antiepileptic medication.
If I suspect because I find neurological abnormality or I've done diagnostic tests that show a structural brain disease, then in addition to treat the disease, if it's treatable, you need to put the dog on or the cat on symptomatic antiepileptic treatment. If the animal is having not very frequent seizures, but after the fit, he may be very aggressive, or if you've got a 90 kg grade then having cluster seizures maybe every 2 months or 3 months, but when it's happening, it lasts for a whole day and the dog is very confused. It's difficult to manage in the house, then it may be enough for the owner to decide to start a drug even if the frequency is every 2 to 3 months.
Otherwise, the rest is very much a school of thought. A school of one school of thought, consider what you need to treat after the second seizures. On the basis that the sooner you treat, the more likely you will control the feet.
And this is mostly based on human evidence. The other school of thought is to treat when the the seizures start to affect quality of life or enter a point where there are at least 1 or more than 1 a month. And this is very much the school of thought I tend to follow because we've all seen dogs maybe having one fit.
And then 2 months later, another one. They, they have 2 ft there, and some people will start on the epileptic drug. But this same dog may not have any feet for 6 months after that.
So, that's why I prefer to monitor the dog. And if he's having 1 or more than 1 a month, then personally, that's where I will start treating. Treating an epileptic dog or cat is a lot of client education.
And there are a number of messages you need to give to the owner. The first one is that an animal with idiopathic, which we refer as primary epilepsy, is a normal animal. Most of the feet tend to occur out of the blue when they're not expecting.
And therefore treat the animal normally. Don't stop enjoying life with your dog or cat. Don't stop taking them for a walk or playing with them.
The aim is not to cure, but to control is an expectation you need to set from the start. To also tell them there is no quick fix, most of the medications take time to work, and very often they will be, good, good time and the less good time is very much a roller coaster in a lot of, of animal. To tell them about potential side effects of anti-epileptic medication and when to be concerned and when not to be.
Some of the drug we to use what matters is the blood level. And that will determine the therapeutic and the toxic effect. To stress to the owner, not to change the medication or alter the dosage without consulting you.
And also very important to keep a recall so you can see and assess is the animal objectively improving or not. As I say, a lot of the drug going to use. They are defined therapeutic range where we know that 90% of the population will respond to treatment above that range is the toxic level and below the therapeutic level.
So we may have to refer to this therapeutic monitoring, blood monitoring in order to monitor the treatment, at least for some of the anti-epileptic drugs we're going to use. What are the drugs available for dog and cat? They are listed there.
But in terms of licenced drug, there's only licence for dog, and the licence for first line treatment are only given to phenobarbital and mitoine pion, at least, for both of them in the UK. And hebitoin in Europe as well, and I think they're getting licenced in other parts of the world and bromide is a licenced as an adjunctive phenobarbiton in refractory case. All the other drugs are human antiepileptic drugs that we'll be using out of licence, and in cats, none of the drugs will have a licence.
What not to use diazepam in dog orally is not an anti-epileptic drug because the half-life is very short. There is rapid autoinduction that will reduce the half-life even more. They will do on, benzodiazepine orally will develop rapidly functional tolerance, and this benzodiazepine, especially diazepam, can be patotoxic.
For this reason, it's pointless to give oral diazepam to prevent seizures occurring. So they are not an anti-epileptic drug. However, using IV they are an anticonvulsant benzodiazepinem.
In dog, two first line treatments, phenobarbital and immipitoine. Phenobarbital is a long acting barbiturate that acts mostly at the GAA receptor. It increases the chloride conductance, also have some effect in the bibi glutamate.
There is different formulation tablets, but also solution that can be good especially to those small dog where a tablet size may not fit for the body weight of the dog. And phenobarbiton is used at the starting dose of about 3 weeks per cake twice a day orally. It can be given twice a day because the initial half-life is anywhere between 37 to 89 hours, which allowed twice daily dosing.
And we know that a dog on phenobarbital, about 3/5% will respond to it, which means that there is still a 25% of dog that will not respond. Effectively to phenobarbital or may respond initially and then develop pharmaco resistance. For phenobarbital, there is a defined therapeutic range where we know that 90% of the population of dogs tend to respond, which in the milligrammes per deciliter is 20 to 35, while in minimum per litres is anywhere between 70 to 150.
So ideally, at the start, we want dog to be within the therapeutic range. And if they are above this range, they are more likely to have toxic effect, especially liver liver side effect. In dog, the half-life is, as I say, about, 2 days, and therefore, the time it will take for the dog to have steady state serum level is 5.5 times this half-life, which is about 2 weeks.
And that's the time you will need after starting anti-epileptic drug to do a blood level to determine what is the steady state serum level and ensure that at the beginning, it's within the therapeutic range. What you need to know is that in though with time, the phenobarbitum will induce its own metabolism by inducing liver enzymes, and the effect will have to reduce his half life. Consequently, if a dog was initially in the therapeutic range with time, the serum level, month after month, sometimes it may take years, the blood level will slowly drop below the therapeutic range.
Hence why you need to do regular blood tests. To prevent that, and you may have with time to increase the number of tablets to maintain the same blood level. Again, with phenomarbital, what matters is not the quantity of tablets in the mouth, it's how much of the drug is within the bloodstream.
When should you do blood monitoring of phenobarbital? Well, 2 weeks after starting the drug, a steady state. If the owner keep a diary and they notice that the frequency increase, then you need to instruct them to come to see you.
Then you do a blood test to check that the level hasn't dropped, and if it does so, you need to increase the number of tablets. I will do that as well initially every 3 months. Proactively for the first year and if everything goes well every 6 months.
I will also do that if the dog needs to be treated for another condition using any of the drugs listed there, steroids especially. I will do a serum level before I start steroids and then 2 to 3 weeks later to make sure that this hasn't caused a drop in serum level. If you suspect there is a side effect, if the dog starts to be bumping into things and being toxic, check that the level hasn't increased and it may have been increasing because there's an error with the dosage, or maybe, maybe the dog is developing liver disease and is unable to metabolise yobarbital.
And also any time you're going to change the blood level, make sure the oral dosage, make sure that you check 2 weeks later what you've achieved. Don't assume that if you increase the number of tablets by 20%, the blood level will increase by the same percentage. There's been a lot of speculation about when should you do blood level of phenobarbital.
Ideally, it's best to do it before the next dosing. However, it's been shown that if you have a steady state serum level, as the name implies, there should be minimum fluctuation between the interval of administration. So what I would recommend is to do it always at the same time on the same dog.
So you've got something to compare. Otherwise, ideally do it before the next dosing, but that may mean early in the morning or late in the evening, which may not be practical with your clinical activity. Also, often colleagues tend to advise giving phenobarbital exactly 12 hours.
Well, there's no need to do that. If you give within 10 to 14 hours, it's perfectly acceptable. If you have a steady state serum level, the level will not drop dramatically at 12 hours and 1 minute.
So try to make life easier for the owner. So, this is the, the kind of protocol I will follow when I start in the barbi and I start at 3 weeks per twice a day. 2 weeks later, I asked the owner to come back to have a serum level.
If the serum level is within the therapeutic range, then I asked them to come back 4 weeks later. Because of the 02 enzyme induction, which tend to be quite high at the beginning, and then I will ask them to come every 3 months for the first year and then every 6 months. If the level is below the therapeutic range, then initially, I will increase the oral dosage maybe by 20-30%, repeat the level two weeks later to ensure that now I've got, I'm within the therapeutic range, and if I haven't managed that, I will keep increasing until I do so.
If the level is above the therapeutic range and the animal is not having any side effects, then I'll keep the dog on that dosage repeat 4 weeks later, and only if the level is above the therapeutic range, then I will reduce the dosage by 20 to 30% and recheck the level to make sure I'm now within the therapeutic range. After that, what decision I will make about the dosage? Well, the priority is to go with the clinic and the clinical effect, which means do you have a positive effect, reduction in the frequency.
And making sure you don't have any side effect. The serum level will then come as 2nd in my decision about changing the dosage. So for example, if I got a dog within the therapeutic range, but there is no change in the frequency.
Then the next step would be to see, well, if I'm at the bottom of the therapeutic range. Or in the first half, I still have margin to increase again the serum level, so I'm going to increase the number of tablets to push the serum level to now the top end of the therapeutic range and see if it helps controlling the feet. Similarly, if I've got a dog that is below the therapeutic range but is having no seizures, then I'm going to keep monitoring.
And if he's having fit again, then I know why I will need to increase the, the oral dosage. So you see that the priority is very much the clinical effect and then use the blood level as a second factor to decide about the dosage. Sometimes you can't wait really 2 weeks and you need to get quickly within the therapeutic range and how I'm going to do that, I'm going to use intravenous phenobarbiton, which is very important to have in your practise.
And the loading dose is 18 mixs per kick. You can go up to 24, but instead of giving it in one go, I will give bolus of 3 mixs per kick. Every half an hour for 6 times.
And by doing that within 3 hours, I can reach the therapeutic level. And then put the dog on a maintenance oral dosage. What are the side effects of phenobarbital?
Some of them are idiosyncratic, some of them are transient and those related. Hydrosyncratic means they are not related to the dosage or the time. And they are hyper exitability.
Some dogs very, very rarely may have acute hepatotoxicity and probably a more, more frequently may have bone marrow dysplasia, which would be anaemia, neutropenia, thrombocytopenia. If you have a hydrosyncratic side effect, you have no other choice than stopping the phenobarbital to address them. While with those related or transient.
Side effect. If there are those related, then they may respond to reducing the dosage of phenobarbital. So transiently a dog on fidobarbital may initially be wanting to eat and drink more, maybe a bit more sedated, maybe a bit more toxic, but within 2 to 3 weeks that should improve and if not, you will have to reduce the dosage.
You may know that phenobarbital physiologically can affect the liver. And it will cause moderate increase in liver size. However, if you do an ultrasound, it should not affect the ecogenicity nor causing any, any histological change.
It will cause as well increase in ALT and ALKP due to enzyme induction, which is physiological with phenobarbital. However, you don't expect any changes in the ASTB rubin or balacid. Hepatotoxicity can happen with yobarbital, mostly when the dog has been maintained at levels that are above 35 milligrammes per litre from the toxic level, not all the time, but mostly even.
You expect the dog to show clinical signs of liver disease, and if you have to investigate, then you rely on parameter, but you don't expect physiologically to be affected by pilobarbital. And they are listed here and probably the best one is to do a balay stimulation test to assess the function of the liver. If the balacid is abnormal, then my next step would be to do an ultrasound and to do a biopsy when I any of the liver.
To define what is the type of liver disease that this dog is suffering because it may be related to phenobarbital, but it may be comorbidity as well. So very important to establish a diagnosis of liver disease on what type before to make any decision. If you have hepatotoxicity, then you have no other choice than stopping fidobarbiton and we're going to address that in a minute.
In cats, phenobarbital can cause side effects, but they are hydrosyncratic. Phenobarbital has never been reported to cause liver disease in cats so far. But in terms of hydrosyncratic side effect, phenobarbital in cats can cause bone marrow dyspraxia, so thrombocytopenia, neutropenia, severe cutaneous eruption.
But the one I've seen mostly is marked lymphadenopathy, also known as pal lymphoma. Typically, idiosyncratic side effects occur over the 1st 6 months or 6 to 8 months. And very important to know actually this pseudo lymphoma because very often, you may not think of phenobarbital and then you got a cat presented to you a few weeks after starting phenobarbital, being lethargic, not eating.
And on examination, you see that there is generalised lymphadenopathy. And quite understandably, lymphoma will be high on the list. So again, important to do an F any of the of the leaf node, but unless there is a, a neoplastic population, then you're dealing with an idiosyncratic reaction to phenobarbital.
The other first line treatment in dogs is a newly licenced anti-epileptic drug called limipitoine released about 4.5 years ago under the name of PExion. There is a number of advantage in using that drug.
The fact that he has a quicker motorfaction, he worked within 48 hours while phenobarbiton takes 2 weeks. Is, metabolised by the liver, with, it doesn't cause any liver enzyme induction. So, and there is no need for regular blood tests.
There is no evidence that it can cause liver toxicity. The starting dose is 10 beats per kick and you need to increase to then 20 and then 30 to effect on a weekly basis, depending on the response. The efficacy was reported to be comparable to phenobarbital.
However, there will be a circumstances where I would not advise this infection, would be a dog having cluster seizures. And we know that phenobarbiton will be much better. Personally, I tend to prefer phenobarbiton by infection and reserve peion for dogs that have infrequent seizures maybe every two months where or plus where the owner wants to put to start the dog because they distressed by the feet.
If a dog has 1 a month or more than 1 a month, I much prefer using Philobarbitone. There's a personal choice. So within that in dog first line treatment, phenobarbiton orexion, I give you my preference.
InA will also use phenobarbiton as a first line treatment. So what to do when things are not doing well on first time treatment? Not doing well happened in about a quarter of cats and dogs.
And not doing well maybe means that we're not fulfilling the aim of the treatment, which is controlling the seizures with no side effect or minimum side effect. So it may be that we've got too much side effect. And all we have for severe control.
Very important when things are not doing well, to go through a checklist. And the first one is to ask yourself, well, am I dealing with an epileptic seizure? And we've seen an example of the paroxysmal dyskinesia, which is the most common mimic of epileptic seizures.
With dyskinesia, the animal is aware of his surroundings. There is crumping and the event can last more than a few minutes. There is no autonomic sign, there is no as well no ah procyclal sign.
If you are sure you're dealing with an epileptic seizure, even better, you got a video. The next step is to make sure that there is no underlying cause for the seizures and it's effective idiopathic epilepsy. So of course, if the dog has had fit for about 2 years and it's totally normal in between on the examination, then it is idiopathic epilepsy.
But if it's more recent, then that's where I will advise to do further tests, blood MRI and CSF. Making sure the animal is on the right anti-epileptic drug as well for the species. Making sure it's on the right dosage.
So we're going to look at the scenario to see how you're going to base your decision about adding or replacing by another antiepileptic drug, looking at how we trying to address control of the feet and or side effects. You go without saying that if you got a dog onexxion and he's not doing well, then what I will do is make sure I'm using the dosage up to 30 per twice a day. And if I'm doing so and if it's not responding adequately in terms of seizure frequency, then I will add phenobarbital to the Pexxion.
If the dog is on phenobarbital. And the dog is having no side effects but he's not responding well. The first step should be, should be for you to do a serum level.
If the serum level is in the bottom half of the therapeutic range, then I will increase the number of tablets, check that the serum level now is at the top half of the therapeutic range and monitor the frequency to see if it's responding with a higher dose. If the dosage is above the therapeutic range, then I will avoid, obviously, increasing further, but I will start another anti-epileptic drug. And there, what choice you've got, you can add pion and there is nothing wrong adding the two.
Some studies have saw that adding the two together in a case like that where they don't respond to a single one is better. Ami bromide, if the seizures are not too frequent. But they require a better control or I may use levetiracetam.
If the Level is above the therapeutic range, when the dog is well controlled, then I would try to reduce the phenobarbital level to maintain him within the therapeutic range. If the dog is having on phenobarbital, but poor seizure control, but on top of that is having side effects, then the decision depends very much on what type of side effect. If I've got on the right any of the idiosyncratic side effects, especially bone marrow dysresia, which is an emergency that you need to address very quickly when you have no other choice than having to stop the phenobarbital, and I will do that within a week.
But as I start reducing the phenobarbital over a week, I'm going to start the dog on another antiepileptic drug. You may want to use Pexone. However, if the dog is not responding to phenobarbital in terms of frequency, then I doubt you will respond to Pexion.
And in that particular case, I would prefer to use, levetiracetam. So I start them on levetiracetam. And then slowly reduce thearbiton over a week, hoping that the levetiracetam will take over.
If I've got more dose related side effects on a dog that is not responding well to phenobarbital, then I will have to add something else while reducing the phenobarbital to address both the seizure control and the side effect. We need to be very careful at what anti-epileptic drug going to use, especially making sure that the side effect of that additional anti-epileptic drug doesn't, are not the same as phenobarbital. Particularly if you have PPD polyphagia but also ataxia sedation, I will avoid using bromide because that will only add to the side effect of enobarbital and I will prefer in that case to use levetiracetam.
If I've got a dog on yobarbiton that is well controlled, but is having side effects, if the side effects are hydro syncratic then same as before, I will add. Another anti-epileptic drug and you may useexxion here because, you know, it seems that the dog is not too bad in terms of seizure frequency and phenobarbital did the trick. I will use pion and then over a week, reduce the phenobarbital.
If the seizures come back, then you may need to use another anti drug and use levetiracetam. If he's on phenobarbital, well controlled, but he's having side effects that are dosage related, then I will try to reduce phenobarbital by 20 to 30%. See if we help reducing the side effect while maintaining the control of the city.
If not, we come back to the previous scenario. Otherwise, when everything goes well, then I tend to keep the dog on the same dosage and do blood tests every 3 months for the first year and then every 6 months after that if everything goes well by doing not only serum level but also CBC and biochemistry. To to monitor for side effects of phenobarbital, especially bone marrow dyspraxia.
Of liver disease. So what kind of additional antiepileptic drug we can use? Bromide was the one that we used to use in the past.
Probably about 20 years ago when I started doing neurology, it's a salt, as you know, and therefore it's very important to maintain the salt content of the diet the same. He at the GAA receptor by increasing chloride conductance, so it has a synergistic effect within the barbiton. The dosage of bromide is 30 mL per gig once a day.
However, some dogs may be overly sedated at that dosage after giving the, the, the, the, the medication, or they may have GI upset, vomiting, especially as it can irritate the gut and in that case, you may want to split the 30 mL per ke into 150 mg per kg twice a day. Bromide has a very high half life, 25 to 46 days, which means that you can give it once a day. However, the downside is that steady state will take a minimum 3 months to be reached, and that's when you need to do a serum level to ensure that serum, therapeutic level has been achieved, which is written on this slide.
If you need to give bromide, because the owner can't afford giving, for example, more expensive drugs like levetiracetam and you need to get on a quick control of the feet, for example, not responding to phenobarbital or you need to stop phenobarbiton, then you have no other choice than loading the dog on bromide. The total loading dose for bromide is 600 milligrammes per kilogramme. However, you don't give it in one day, you're going to give it over 5 consecutive days, which make a daily dose of 120 mL per kg per day, to which you need to add the 30 mL per kg maintenance dose.
So all in all, a loading dose will be done by giving 150 milligrammes per kg per day over 5 consecutive days, and on day 6. I will do a serum level and you should have achieved about 90% of the therapeutic level and start the dog on maintenance. Do.
When you do loading dose, I will recommend you keep the dog hospitalised because it's likely to be quite sedated, quite a toxic. And not giving this 150 milligrammes per kilo, in one dose, but maybe in 3 or 4 dose throughout the day. Side effects of bromide, some of them are shared with phenobarbital, PUPD polyphagia, ataxia and sedation, and that's why if you're concerned about the side effects on the dog on philobarbital, adding bromide will only add fuel to the fire.
It can also cause skin rash, hyperactivity, restlessness, and combination of yobarbital cause pancreatitis. Levetiracetam is one that I tend to use quite a lot. Remember, in the referral population, we tend to see the difficult epileptic dogs.
So, but likely explained why, you know, we use it more, maybe what we do in first we don't practise. Levetiracetam, is used as starting those 20 to 40 mixs per kick, given 3 times a day. And if you're now working.
It may be not possible for them to give the midday dose. So what I would advise is for them to give the first dose before they go to work, as soon as they come back from work to give the middle dose and the third dose to give it just before to go to bed. In North America, we are lucky to have a slow release form of levetiracetam which we don't have in Europe.
But it's overall a very safe drug, and the side effects are limited to to some dogs may be a toxic or lethargic. But the main downside is the cost. It can be a very expensive drug and it's best to use the generic form levetiracetam as opposed to Keppra.
I An alternative to give Keppra on a daily basis. If you have a dog that tends to have cluster feet and may have fit for a few days and it tends to happen on a regular basis, is to give Keppra when he's having his first fit until he stops fitting for a few days, so to use it only during the the the the clustering or the few days of seizures period, which can save quite a lot of money. But ideally, I prefer to use it long term.
Alternative to Keppra or if the owner are still keen to try something else and the dog is already on fidobarbitone, bromide, Keppra, and he's still not responding well, in my experience, then it's unlikely that adding another drug is going to make a miracle. But if you are motivated, then the next step would be Zozonizamide, treat them Zonegran. I use a dose of 10 mix per gig BID.
I use it in conjunction with phenobarb and without phenobarb 5s per gig BID. Again, it's a very expensive drug, even more expensive than levetiracetam. Main side effects are liver disease, but also it's a potential sulfonamide, so it can cause a side effect relating to that class of drug like for example, dry eye.
Gabapentin is something that we've tested a few probably nearly 15 years ago and we've shown that it doesn't provide much anti-epileptic effect in dogs. So we, I personally abandoned the use of gabapentin in dogs, but one I will use especially in cats is pregabalin. And it may be my .
Option if the cat doesn't respond to phenobarbital and may add levetiracetam or pregabalin. The treat them being Lyrica dosage for mix packet in cat I will use twice a day. Due to difficult to give it 3 times a day.
Side effects are sedation ataxia, but they are probably, less than we used to have, for example, the gabapentin and this pregabalin, the next generation gabapentin. In dog, it's only been used, very rarely and I don't have personal experience in epileptic dog, but in cat definitely something I tend to use quite a lot when phenobarbital is not doing the trick. Finally, when will I use rectal diazepam?
Rectal diazepam is something that I will use on a dog or a cat that is known to be clustering. So unless he's having more than one fit in a day, I don't tend to use diazepam rectally because what you do in that case, if he's only having one fit a day, you're not trying to prevent anything, but you're going to prolong the postittal phase. I tend to use 1 to 2 mixs per kick given rectally as opposed to the lower dose put on the slide and it's often found in many textbooks.
And I will instruct the owner to give it as soon as practically possible. You may be able to give it during the fit, but if not, straight at the end of the feet to be given after the 1st, after the 2nd, and after the 1st fit. And if the animal is still having on the 4 ft, then to consult you, to call you and to bring you the dog to try to stop this clustering phenomenon.
Remember the owner and if you dispense diazepam and also fiobarbital, they are controlled drug and for this reason, it's very important to keep them in a safe place. That's it for this presentation on maintenance anti-epileptic drug and how to manage a refractory case. I want to thank again the veterinary webinar for inviting me to this two webinars, but also Hallmark Veterinaryaging for sponsoring this webinar.
And again, if you haven't done so, please feel free to join Simon and us and I on our Facebook page, veterinary neurology, where we have a lot of tip and practical, information and a lot of video, to help you to, enjoy neurology. If you have any questions, I'm sure there will be a lot on a subject like, anti-epileptic drug. I'll be happy to answer them.
Thank you very much, Laurent. That was really great. I've got a couple of questions.
One from Alina. When you are checking serum phenobarbitone levels after starting treatment and for routine monitoring, assuming that the seizures are controlled, do you use peak samples or trough samples? So, I'll show you a slide where there's been a nice study that has shown that when you have a steady states on concentration, you have minimum fluctuation within the interval of administration, which means that there is minimum difference between peak and trough.
Ideally, you want to have a trough level which would be just before giving the drug, but that will mean opening your clinic. Very early in the morning or having to wait the end of your clinic to have all your epileptic drugs, epileptic drug to do the serum level, which is not very practical. So, I will advise to do the blood level always roughly at the same time on the same dogs.
We've got way to compare. Thank you. I'm getting a lot of comments and just saying how helpful your webinar's been, really practical and, and many, many thanks.
Janine is just asking if you have any experience with VNS implants. No, I don't have actually any implants, so I won't be able to tell you much about it, I'm afraid. That's OK.
And tested in, I know it's been, it's been tested in dog, so I think what his space at the moment. OK. Another one from Janine, can you use illio during the post-ittal phase, which I think is that alpha 2.
For the phase. Well, I mean, it all depends, you know, how bothering is the postal phase. I would say most of the time it's something, but, you know, the dog and the owner has to ride, to be honest with you.
I don't tend to medicate, you know, the dogs for the posteral phase. Very often these dogs are wobbly and confused. I think adding any drug is likely to actually prolong that phase.
So the answer is I personally don't, you know, recommend. But I don't have a, a personal experience with that drug. OK.
OK. And what is your first option drug to use, for an epileptic cat? I will use phenobarbiton.
So, dog, I use phenobarbital, cat, I will use phenobarbiton first line treatment. Perfect. So I've just got one sort of case study here from Leonie.
She's a 4 month old pup, it's had two seizures, completely normal in between, nothing on bloods, although not yet done a bile acid stim test. Only other finding has been diarrhoea. Do you think this age is unusual and, and should she look for anything else?
On a dog like that, probably I will do a ballast steam. I will expect with a dog with a congenital protaemic shunt to show at least some abnormality in between the feet. The dog may be encephalopathic, you know, bumping into things a toxic, lethargic.
However, you know, I think for everyone's sake, it's best to do a blast. On a dog like that, if it's totally normal, I will probably monitor and I will not rush to put the dog on antiepileptic drug. It may be that he will not have any more feet for the rest of his life, but it may be a dog with an early onset idiopathic epilepsy.
So in dogs they tend to start between 6 months and 6 years of age, which means that if the dog starts within that age range, the balance of probability. Is more in favour of idiopathic epilepsy than something else. However, you may still have idiopathic epilepsy if you start before 6 months or later than 6 years of age.
So possibly it could be an epileptic, an idiopathic epileptic. On that dog, as I say, I will do a balay just to fully roll out the shunt and then monitor the dog for further fit and only start antiepileptic drug if it's happening on a monthly basis. Thank you, Laurent.
Just another one coming from Paul. How often and when would you try a special diet for suspected idiopathic epilepsy? And have any diets been successful?
Well, I mean, I'm sure if you, if you listen to the food manufacturer, that's what they will want you to assume. Of course, they can't claim that it is to treat epilepsy. I will say that it doesn't harm.
Do I strongly believe it will have an effect in controlling the feet? I'm still sitting on the fence personally. It's been shown, however, that it may help with behavioural changes that may be associated with epilepsy.
So that may be a reason, you know, to give it, to give the diet. So apart from that, as I say, I stay very much on the fence. OK, and then, and then just a couple more again, just saying a great lecture.
Thank you. And then it's really just to let everyone know if if there is any more, questions, do pop them in the Q&A box at the bottom. But everyone's just really grateful.
Thank you so much, Laurent. These webinars are all recorded and should be available on the webinar vet website next week if you feel like you've missed it.
