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Pexion 400mg
Simple steps for pet prescriptions
  • 1Get a prescription from your vet
  • 2Place your order with Pet Drugs Online
  • 3Attach a prescription and tell us about your pet, read more
  • 4Our vets will double check your order
  • 5Your order is dispatched right away
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Pexion 400mg

This item requires a vet's prescription

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  • Vet price £1.18
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Prescription Info.
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Pexion 400mg

Pexion 400mg is for the treatment of primary epilepsy in dogs.

 It is a white, oblong tablet supplied in 100 and 400mg tablets, either individually or in packs of 100. (100mg tablets can also be found on our website).

Pexion is used for the reduction of the frequency of generalised seizures, due to idiopathic epilepsy in dogs. This medication is to be used after careful evaluation of alternative treatment options.

Pexion is a prescription item and will be sent once a valid prescription is received. Please follow the instructions given by your vet.

How does Pexion work? Pexion acts on a specific receptor in the brain cells to help reduce the amount of excessive electrical activity. Therefore, like other epilepsy medications, it reduces the amount of seizures your dog has.

The medication is intended to be administered twice daily (12 hours apart) and the dose depends on the weight of your dog:

5kg - 1/2 x 100mg tablet

5kg to 10kg - 1 x 100mg tablet

10kg to 15kg - 1 & 1/2 x 100mg tablet

15kg to 20kg - 1/2 x 400mg tablet

20kg to 40kg - 1 x 400mg tablet

40kg to 60kg - 1 & 1/2 x 400mg tablet

Over 60kg - 2 x 400mg tablet

How long does Pexion take to work? Pexion starts to work within a few hours. It will take a little while before any improvements are noticed in regards to the dog's seizure patterns. This may be because your dog only experiences seizures every few weeks or it can take a short time for your Vet to find the correct dose for your dog.

Do not use Pexion in dogs with severely impaired hepatic functions, severe renal or cardiovascular disorders.

Once the packet is open, the product's shelf life is 8 months.

This is a prescription item and will be sent once a valid prescription is received.

To check the most up to date information about this product, please read its Summary of Product Characteristics (SPC) on the Veterinary Medical Directorate’s (VMD) Product Information Database:

View summary of product characteristics (SPC)

For orders over £29 postage is free. For orders under £29 we charge £2.99 for postage

For Light items (under 2kg) our standard method is Royal Mail Second Class (there are a few exceptions, so if in doubt check our Delivery page).

To get it faster you can upgrade Light items to Royal Mail 1st Class or a Guaranteed Next Day Courier service, Saturday Courier or even before 12 noon services. There's a small fee, but if you're in a hurry they are worth considering. To qualify for next working day delivery, orders must be placed before 12 Noon Monday to Thursday. There is no standard Saturday courier delivery.

Heavy items weighing 2kg and more are sent via courier. If ordered before noon Monday to Thursday, Heavy items will be delivered next working day. Heavy items ordered after 12 Noon Friday, or anytime Saturday and Sunday will dispatched on Monday for a Tuesday delivery.

Please note that if you are purchasing a mix of Light and Heavy items at the same time, these will be sent separately. The Heavy items being sent by Courier, the Light items by Royal Mail Second Class.

All exceptions to these guidelines are noted in the product description.
For more information, view our Delivery page.

If you see the "prescription required" sign next to an item you’d like to order, it means the item can only be issued with a prescription. While you can add these items to your shopping cart and pay for them along with other non-prescription products, we can’t dispatch them until we’ve received a prescription.

Product reviews for prescription products are not allowed by the RCVS. But here is what our customers say about our service:

Service reviews have been compiled from 37762 customer reviews




Very easy to order, from medication to food. Found the items I needed a good 30% cheaper than purchasing from the vets. Very quick delivery too with the delivery company they choose sending texts and an hour time slot that the delivery will be, if you can’t make that time, easy to change to suit you.


Great value for money, superfast delivery as usual, way faster than I would expect it to be. Though this time delivery was delayed by a day because of the snow. But I was informed about it at the time of purchasing as well as all along the way.


Excellent fast, first class service every time!


First class service every time.


i purchased hills zd wet dog food as my shitzu needs sensitive food prescribed by my vet I find that pet drugs online is very competitive with their prices and delivery I will use them again and recommend them.


The price of product and delivery service were superb - just what I wanted from an online retailer. Many thanks for the super service - I intend ordering all the cat products I need from you in future.


All good. Would use again.


Just tablets, but they arrived by post the next day, much cheaper than the Vets, perfect, thanks I`ll use them again. big thanks


Always had great service fast delivery & any queries with a order.orva prescription They telephone or e.mail would recommend to anyone so much cheaper than your vets

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