What is a seizure in dogs?

A seizure (or ‘fit’) occurs when there is abnormal electrical activity within the brain. If the whole brain is affected by this electrical activity then this results in a full or ‘generalised’ seizure, where there is a loss of consciousness, involuntary repetitive movements (e.g. paddling of the limbs) and urination and defecation may also occur.  If only a portion of the brain is affected by the electrical activity, then the dog may have a ‘partial’ seizure. The appearance of a partial seizure can vary according to which part of the brain is affected, but for example can present as muscle tremors/spasms, hallucinations or abnormal sensations.

Whilst seizures can certainly be unsettling and unpleasant to witness, please rest assured that your dog does not experience any pain and is largely unaware of the whole process. Afterwards, they can appear disorientated or confused, potentially exhibiting abnormal behaviour that can include aggression in some dogs. This is called the ‘post-ictal’ phase and can be very short in some dogs, whilst it lasts longer in others. Please reassure your dog and offer them space to recover in their own time, undisturbed by other dogs or children, for example.

What causes seizures in dogs?

The most common cause of seizures in dogs is epilepsy – it is an inherited disorder, but the cause of the condition is currently known. Given it is inherited, certain breeds are more predisposed to developing epilepsy than others. For example, it is more common in Labradors, Golden Retrievers, Beagles, Shetland Sheepdogs, Vizslas and Keeshonds.

Other causes include toxin ingestion (e.g. xylitol, slug bait, chocolate), low blood sugar level (e.g. insulin overdose), liver disease, lungworm, head injury, brain tumours and kidney failure.

What should I do if my dog has a seizure?

• Stay calm.
• Try to reduce all stimulation – this will increase the chance of the seizure finishing quickly.
  • Turn the lights down low and close the curtains/blinds
  • Turn off background noise
  • Remove other dogs/animals and children
  • Try to resist the temptation to cuddle your dog
• Make a safe area around your dog – move furniture out if the way if necessary and feasible.
• Do not put anything in your dog’s mouth – they cannot swallow their tongue so do not worry about this.
• Remember to time the seizure and keep a note of this in a seizure diary.
• Your vet may have prescribed emergency medication (rectal diazepam) to reduce the length and severity of the seizure.
• If the seizure lasts longer than 3-5 minutes, then call your vet as it is likely that your dog will need to be seen as an emergency if this is the case.
• If your dog has repeated seizures within a 24-hour period (cluster seizures) then please call your vet for advice, as again it may be that they need to be seen as an emergency.
• Once the seizure has finished, make sure you reassure you dog but give them space to recover in their own time.

How are seizures in dogs treated?

Most seizures are self-limiting, meaning that the dog will come out of the seizure on its own after 1-3 minutes. In those cases, follow the advice above to increase the likelihood of the seizure stopping on its own.

If a seizure is longer lasting (>5 minutes) then you must speak to your vet immediately, as they may need medical intervention to come out of the seizure. In this case there are various medications that we can use and can even put your dog under general anaesthetic to stop the seizures if other medication is not working.

Once stabilised, we would try to work out why your dog has had a seizure, looking at factors such as their age, breed, severity of the seizure, underlying medical conditions and any known toxin exposure. Seizures that are caused by toxins may need to be treated in a particular way.

The vet would run some blood and urine tests to rule out various causes of seizures. In order to diagnose epilepsy, we technically have to rule out all other possible causes of seizures, and so the vet may suggest that you dog is referred for more advanced tests such as an MRI scan. However, this is obviously not always an option, due to limited finances for example. In those cases, the vet may suggest trial treatment.

Anti-seizure medication is usually only started once the seizure frequency and severity increases, and it does not eliminate seizures entirely, but makes them more manageable again. Various drug options are now available, and the vet will discuss these with you in order to decide which is the best option for your dog.

What is the prognosis of seizures in dogs?

The prognosis will depend on the cause of the seizures and how well the dog responds to initial treatment, if needed. Most dogs that are diagnosed with epilepsy will be well managed on anti-seizure medication and will live a fairly normal life. Some dogs, however, will prove more difficult to stabilise and the vet will need to prescribe combinations of medications in higher doses to try to find what works best.