Wednesday , 29 July 2015
Home > Health Care > A New Treatment for Canine Idiopathic Epilepsy: Pexion
A New Treatment for Canine Idiopathic Epilepsy: Pexion

A New Treatment for Canine Idiopathic Epilepsy: Pexion

We recently wrote about canine idiopathic epilepsy, a form of epilepsy where the cause remains unknown. Today we are looking at a new treatment; Pexion.

The severity of epilepsy can vary greatly between individual sufferers. Some dogs may experience a single, isolated seizure, whilst other can experience multiple seizures every week.

Recently Boehringer Ingelheim has announced their latest product for the treatment of canine epilepsy, Pexion® (Pexion) an alternative to the traditional phenobarbital or potassium bromide treatments given to epileptic dogs.

Are you using Pexion?

If you’re dog has been prescribed Pexion, let us know how your dog is getting on in the comments below. Join the discussion on how other dog owners are getting on with Pexion and keep the community updated with your progress. 

What Is Pexion?

Unlike other treatments for canine epilepsy, Pexion contains the active ingredient Imepitoin. Imepitoin acts in a similar manner to previous anti-epileptic medicines, potassium bromide and phenobarbital, in that it works to suppress electrical activity in the brain.

Imepitoin partially activates GABA receptors, which are responsible for reducing electrical activity between nerve cells. This partial activation of the GABA receptors is believed to reduce electrical activity and help prevent seizures. Specifically, Imepitoin also has a weak blocking effect on calcium channels that allow electrical signals to be propagated along nerve cells.

See here for more information about Pexion 

Does Pexion Work?

A study conducted on Pexion during its development compared it to the traditional anti-epileptic medicine phenobarbital. A 20 week study of 226 dogs taking the medications found Pexion matched phenobarbital in efficacy, reducing the occurence of seizures by around 50%. 1

Is Pexion a Better Alternative?

The Pexion study showed that it had an effectiveness equivalent to phenobarbital, however, Pexion may be considered a better alternative as it has less severe side effects.

Unlike phenobarbital, Pexion does not pose a hepatotoxicity risk (liver toxicity). This means the regular testing required to ensure that a dog’s liver remains healthy is not needed whilst being given Pexion.

Treating the Epileptic Dog

It is commonly cited that around 0.5 to 5% of dogs suffer from some form of epilepsy, the severity varying between breeds and individuals. In dogs where seizures occur infrequently  owners may consider not using any medication at all, avoiding the side effects associated with anti-epileptic medications.

In dogs where seizures occur more freqently, such as once a month or more, treatment should be considered.

The introduction of Pexion gives owners and vets a greater choice when it comes to treatment, but does not replace phenobarbital and potassium bromide.

Owners should consult their vet and explore all the possibilities when dealing with an epileptic dog.

Seizure Types That Require Immediate Veterinary Assistance

Cluster seizures – When multiple seizures occur in one 24 hour period
Status epilepticus – A persistent epileptic state that lasts for longer than 5 minutes

For more information about epilepsy, such as the causes, what to do during a seizure and more, see this article.

Disclaimer: This article was written as a response to the release of Pexion and as a follow up to a previous article concerning idiopathic epilepsy. I am not affiliated with the product (Pexion) or the manufacturer (Boehringer). 

Image Credit: Onkel_wart

About James Watts

BSc Bioveterinary Science. Editor of PetSci. When I'm not writing, learning, discussing, or reading about animals, you know it's the weekend!


  1. I am a UK national living in Costa Rica, it is comforting to be able to share our experience with others, we have a three and a half year old male beagle who started experiencing seizures in May of last year, since then they have increased to cluster seizures every two or three weeks. I fear we are losing our battle with his seizures and that we are constantly one step behind, he was started on dilantin and then switched to primidone and then phenobarbitol because primidone is difficult to get here, I thought we had made a breakthrough administering him with hemp oil drops three weeks ago but then he suffered his regular bout of around nine cluster seizures two nights ago, we administer dizepan rectally, this is a brutal disease and we sense we are running out of time and options,

  2. My 7 year old Labrador is currently on 1000mg Keppra 3 times per day, 400mg Pexion 12 hourly and 3.6ml of Potassium bromide daily. Her seizures definitely improved in the 1st year on Pexion and then as many are saying they have increased drastically where she has had 6 grand mal seizures this month. She was taken off the PB as had liver issues and vet isn’t willing to use it again. I am feeding Eukanuba Dermatosis, adding vegetables and giving Krill oil, Vit D3, Vit B complex and grape seed extract daily and still no joy. She is ravenous for 3 days after a seizure and eats anything -paper, skirting boards, her bedding and will snap at your hands if she thinks there is food there plus giving her tablets is a nightmare as she grabs and has punctured my skin frequently. I am running out of options with medication and am feeling so disheartened as I don’t know how to help her anymore.

    • Anyone needing help and support from other people around the world who are dealing with canine epielpsy can join a great group with hundreds of members worldwide who are in the same situation. Here is the link: From there you can join the group.

      • To all who are struggling to get the right treatment for their dog, please look at what food you are giving them. I give my border collie dry food from The Natural Dog Food Company plus Omega 3,6 & 9 from Treasure your Health. He weighs 18kgs and he has 400mg of Pexion twice a day and nothing else apart from a dentastix, no other treats and his last seizure was the 10th December last year.

        • Each dog with idiopathic epilepsy is unique and triggers are different. Further more if you go look on websites regarding epilepsy, American ones especially are recommending a natural raw diet. Chicken bones are a natural source of taurine which helps brain function in epileptic dogs. My dog Izzy was among the first to pass away in 2013 after using Pexion and to be honest her natural diet had her looking fantastic, I have found that epileptic dogs fit into 2 categories the first can be controlled by medication and with trial and error there will be meds or diet that works, the other group of dogs will gradually get worse but will pass away young. Human poisons like lawn fertilzer can be triggers that start the disease. Love your fur babies and help them as best you can, sometimes there is nothing you can do.

          • So true Amanda, I could not agree more. The dog either responds or there is nothing you can do to stop progression to clusters, status etc. Distressing disease and pure bad luck….

    • Hi Felicity, I know how hard it is dealing with this awful disease. My 7 year old Golden Retriever Leo has been fitting for the last 3 1/2 years. He is currently on 120mg Phenobarbitone in the morning and 150g Pheno in the evening in addition to 1000mg Potassium Bromide. His dose of Kbr has been reduced twice in the last year as the levels in his blood were too high. He usually cluster fits every 4 weeks, after which he is absolutely ravenous, luckily not the extend of your lab. He underwent a cruciate operation 5 weeks ago and has not had a fit for nearly 8 weeks (which is unheard of). I suspect he had a fit today though as my dogwalker found him very unresponsive and the contents of my kitchen bin was all over the floor (which is always a sign he had a fit). The only thing that has changed is that he came to the end of his course of painkillers on Saturday. I feed him a raw diet, Nutriment and Hunters from Nature’s Menu plus a knuckle or marrow bone once a week. When I first came across Pexion I queried with my vet whether we should change Leo’s meds as his fits were not being controlled with the Pheno and Kbr but the neurologist she consulted was very much against it, stating that if it were their dog they would not use Pexion. I know some have had success with Pexion but it only seems to be only those who have not used anything else previously.

      • I had to euthanase Vicky after several severe seizures two days in a row. Was the hardest decision I have ever had to make as felt I was giving up on her but I know logically I had to do it-my heart just doesn’t agree. It is one of the cruellest illnesses but I had no more options with regards to meds and she was just so tired after continual seizures. Pexion definitely helped decrease the number of seizures in the beginning but the just lost its efficacy. At the end I had doubled her Keppra dose and doubled her Pexion dose and it still didn’t help. I miss my little girl…………………

        • Amanda Kirkman

          Dear Felicity
          I really feel for you, sounds like your lovely dog had the same aggressive epilepsy like my dog had and similar meds with the same outcome. It is the hardest desicion I have ever made and after nearly 2 years still miss my dog and question my choices along the course if her illness. At the end of the day we have both done our very best for our loved one, they wait at the rainbow bridge. Know that although it was a short life it was filled with love too. Some dogs never have that. Sending love and hugs.
          Amanda Kirkman

  3. My Alsatian Sin was diagnosed epileptic a couple of years ago. He was originally prescribed a low dose of epiphen but that’s been increased a lot. Few months ago he deteriorated (cluster seizures and one terrifying bout of status.) .He’s now on pexion as well and though he still seizes from time to time I’d say it’s helped him

  4. My Weimaraner had two seizures in 12hrs and the vet put her on 400mg of Pexion. (32kg dog)
    She has been very good we are unsure if seizure stopped because of pexion or on their own however a little scare to stop tablets now!
    Any advice welcome as to how I can buy Pexion cheaply. currently quite expensive via our vet!!

    • So sorry about your Weim. Your alternative to obtaining your Pexion from your vet is to ask him/her for a prescription. Vets normally charge for this so you need to make sure that you are not going to be paying just as much in the long run – some vets seem to charge an awful lot for a prescription. When I get prescriptions for my dog’s epilepsy (she is on three different AEDs) they are for three months’ worth of medication. I get them from an online pharmacy. You can shop around to see where you get the best price.

    • It’s so good to finally read some positive posts about Pexion. My dog has been on it for 21 months and is doing brilliantly on it. He is 25kg and has 800mg twice a day. He went six months with no seizures last year and hasn’t had one since 11 January.

      I also feed a raw diet which I am sure helps.

    • Dear Wendy, I would not stop with the medication just in case your dog starts having fits again.
      It is wroth checking if your pet insurance covers it, they should.

  5. Hello, just to say that i have a 6 year old lab called Leo. We got Leo 2 1/2 years ago and were unaware of his medical history, on his first long walk with us he suffered a bad seizure and i thought we’d lost him, having no experience with epilepsy in dogs before i was extremely worried, we brought him to the vet and he was diagnosed that day and prescribed pexion 400mg twice daily. He has never looked back and apart from a very occasional mild fit he is in great form. Leo is such a happy beautiful natured dog and it broke our hearts that day to see how that first seizure affected him. I have only praise for Pexion, we havent noticed any side effects and it really does control the epilepsy. If your dog is diagnosed and Pexion is recommended please use it.

  6. hi
    my young dog has a fit once a month and is on pexion 400 one and half tablets twice a day i can cope with this bu he barks for half an hour once he comes round any ideas how i can deal with this as whatever time of day or night i take him in car and drive around roads till he stops

    • Amanda Kirkman

      Dear Jen
      Try putting a few drops of Bachs rescue remedy on his neck during and after seizure. I don’t know why it works so well for being 5 flower essence, but it calms so quickly and is natural.

    • My girl is the same, except because she has clusters that go on for up to 10 hrs she barks non stop from the first fit to the last. The only thing that stops her barking is allowing her to pace around a reasonable size area, usually the garage, living room, or yard. As long as she can pace she doesn’t bark, as soon as she feels confined and unable to pace she barks non stop.

  7. Gillian Hollingsworth

    My 7 year old dog currently on epiphen and libromide but liver enzymes mildly elevated. Advised to slowly swap to pexion but day 1 he is completely ataxic and crying. Day 2 no change. Awful. Not sure whether to carry on old drugs and risk liver damage or to try and change him to pexion. No quality of life at the moment.

    • Jean Collinson

      Gillian,m I see you posted that four days ago but I have only just seen this.

      It is not uncommon for ataxia to be seen immediately but it should wear off. That should happen with the crying, too. If it doesn’t start to lessen in the next day or so then I would call the vet.

      But if you are happy with the epiphen and libromide (my little Dachsie is on both those plus Gabapentin) then there are things you can do to support the liver. For a start, you should give milk thistle. Two of my dogs (one liver dog, one epi) have liver problems but get Hepatosyl Plus to support their livers. Also a liver friendly diet, so no red meat, lots of chicken, eggs, white ocean fish, cottage cheese, ricotta as well as vegetables and pasta, rice or potatoes. Shani also has Epitaur, especially formulated for epileptic dogs – easily available online.

    • Amanda Kirkman

      Dear Gilliian
      Ask your vet if you can keep your on epiphen and libromide just add milkthistle to protect the liver. If you check back on this forum you will note that most of the dogs that have been put down (mine included in september 2013) had been on epiphen previously and pexion didn’t work. Pexion seems to work best on dogs that have not been on any medication. Your vet can keep an eye on liver enzymes with 6 monthly blood tests.
      Good luck.
      Amanda Kirkman x

      • I guess I’m one of the lucky ones. My dog was on Bromide for six months before he started on Pexion. He was very wobbly to start with and tripped over things, but this only lasted about a week to ten days . He has been on Pexion now for 21 months and is doing so well on it. I’ve had to increase the dose three times and he is now on just over the maximum amount so I can’t increase it again, but for the time being all is good.

        Good luck and I hope this ataxia stage passes and your dog does well on it.

    • Don’t worry, I know that it easy to say, but your dog will get used to the drug over 1-2 weeks. the drowsiness, clumsiness etc will pass. My dog Georgie had been on Pexion for over three years, one of the first at our practice to have it. Although it stopped his fits at first, it did need increasing when he started again.
      It is effective at stopping the fits, but you have to be really strict about the empty stomach for 3 hours before and nothing until at least one hour after, in order for the drug to be fully absorbed into the system (vet quote).
      He is now a 13 year old cocker and I don’t think he would still be here without this drug.

  8. My 5.5 year old Chihuahua was put on pexion back in January after the occasional fit progressed to one per week, the vet put her on the mid dose for her size, she has practically every side effect going, increased hunger, hyper-activity, stomach upset, hyper sensitivity to sound. The vet dropped it to half the original dose (50mg twice a day to 25mg), the side effects decreased but did not entirely subside contrary to the information we were given
    This last month we have been fighting severe stomach issues to the point where she is on medication to reduce the levels of stomach acid to try and reduce the inflammation to help it heal. Though we cant definitely pexion was the cause of this another vet within the practice has agreed she should come off the pexion, so far she has not had anymore fits, possibly due to a change in diet (removing certain items from her regular diet), we will not know until the current meds are removed if her system has recovered or not.

  9. my 4yr old border collie Sam is now on Pexion. He started having seizure’s when he was a year and a half, but they were every 3mths or so, but 2wks ago he had 10 seizures in 3 days, which was terrifying…So far he hasn.t had a fit in 2wks. As Wendy said, my dog Sam was very wobbly and uncoordinated when he first started the meds, so the dose was lowered to half a tablet every 12hrs, and he seems fine. Its to early to say if he is going to be OK, but fingers crossed. I just wanted to say its a relief to know I am not the only owner who is alone in this and that there is other caring owners out there in the same boat. My heart goes out to you all, good luck

    • I have a 3 year old border collie and he started fitting when he was 2. He had a scan and was diagnosed as having idiopathic epilepsy. He was started on Pexion but still continued to have a seizure every 10 days/2 weeks. He weighs 18 kgs and his dose was increased to 400 mg twice a day. I give this tablet at exactly 8 am and 8 pm. I also changed his food to The Natural Dog Food Company and I also read that Omega 3 & 6 is beneficial which I get from Treasure your Health, they do an Omega 3,6 & 9. Since he has been on this his last seizure was 10th December, 2014. I am so pleased with how he is doing. He doesn’t have any treats only a dentastix at lunchtime.
      The only side effects of the Pexion are about 9-9.30 he is asleep and sleeps for a good hour or he goes the other way and is charging around like a mad dog and takes quite a bit to bring him back to normal. The vet thinks this is a petty mal which I would rather have than the full blown.

  10. I have set up a Facebook group about Pexion, following my dog being made worse by it and then having many people coming onto canine epilepsy groups, whose dogs had been made much worse and even some dying as a direct result of Pexion. It seems that some dogs respond really well to Pexion while many others are made much worse and have even paid the ultimate sacrifice. There is a petition to get Boehringer to do more research on Pexion on

  11. Hi,

    I Need advise . my dog an Alaskan Malamute has been on Pexion now for 6 months. and he continues to have seizures. they have reduced in number of weeks but have increased by seizures.

    I need to know can I ween him off Pexion. and what would the side effects be.

    Thank you.
    Anne Ryan.

    • First question and most important, what are you feeding your dog?

      • I am feeding my dog Barking heads Chicken Dry product. He has been on this since he was 6 months old he is now 4years.

        • Can I ask you to read through my post I did on the 24th May.

          • Thank you Janet . Yes I have read your post. I have reduced his meds. to 1 a day 400mg. and will continue to reduce further to half a day. I don’t know if this will work, I would rather have him off meds if he is going to have multiple seizures on them.

          • Thee are other seizure medications you can try. My dog has been epileptic since birth, she is now 8 years old and on three different AEDs (anti epilepsy drugs) but has many weeks between seizures now. Between seizures she is just as happy and healthy as my other five dogs.

            It can take a long time to find the right medication and get control so you shoiuld not decide that all meds are the same. Talk to your vet about trying a different medication.

          • my young 3 year old has a fit about once a month the worse problem is about 10 mins after fit she has a good half hour of non stop loud barking has any one have any ideas?

    • There is no need to wean off Pexion, you can just stop it. They say that on the drug info.

      • Please read through this forum, DO NOT JUST STOP PEXION, REDUCE IT SLOWLY. Make sure you have epiphen or other medication in place for 3 weeks or more before you stop the pexion. It may say on the box no withdrawal symptons and you can stop at any time, but my dog was one of the first to be put down in 2013 because I didn’t have the safety net in time to stop the fits. My beloved Izzy was having upto 40 seizures on one day 7 days apart. Speak with your vet and get another medication in place and reduce the pexion.
        Good luck, God bless.
        Amanda Kirkman

  12. A. J. BEAR is 11 years old. I give him PEXION 100MG once daily and he is fine. No seizures in the 4 week period he has been taking PEXION 100MG. I am very pleased.

    • My dog Tikki Alaskin Malamut is on Pexion 100mg for the last six months and has continued to have seizures. after first going on pexion it was seven weeks before he had another seizure, and he had two . I am now weening him off pexion for the last month and now I am giving him half pexion a day . Don’t know if I am doing right or wrong but my vet agrees with me.

    • Really good to read that another dog is doing well on Pexion. My dog is on 800mg twice a day and is now 6 month seizure free.

  13. I set up a Pexion Facebook group a while ago, because so many people were reporting bad adverse reactions to Pexion. Here is the link.

Leave a Reply

Your email address will not be published. Required fields are marked *


You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <s> <strike> <strong>

petsci logo temp 260px

Like PetSci on Facebook

The easiest way to get new updates from PetSci.
We also share interesting news, offers and much more!

Powered by WordPress Popup