Note for Pet Owners:
This information is provided by Provet for educational purposes only.

You should seek the advice of your veterinarian if your pet is ill as only he or she can correctly advise on the diagnosis and recommend the treatment that is most appropriate for your pet.

Idiopathic epilepsy can not be cured, though it can usually be controlled* by using anticonvulsant drugs. (*This means that the frequency and severity of the seizures can be reduced) If your pet is put on to treatment never suddenly stop treatment because this can cause serious, potential fatal fitting.

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Seizures or fits are common in many species, including humans, dogs and cats. The seizures may or may not be associated with primary brain disease. If seizures recur the condition is called epilepsy - and this does not have a single cause. Idiopathic epilepsy is common in some breeds and the primary underlying cause is as yet unknown. Sometimes animals enter a state of continuous fitting. This is called "status epilepticus" and this can be extremely serious - even fatal -  if untreated.


A fit or seizure results when there is a abnormal neuronal activity in the cortex of the forebrain.
Seizures (fits) can be caused by various diseases, of which idiopathic epilepsy is only one : 

Breed Occurrence
The following breeds have been reported to have an increased prevalence for developing idopathic epilepsy the
Bernese Mountain Dog, German Shepherd Dog, Keeshond, Miniature Poodle, Miniature Schnauzer, and the St Bernard. Because there may be a genetic basis for this condition affected animals should not be used for breeding.

Idipathic epilepsy usually occurs for the first time in young adult dogs between 6 months and 3 years of age. Fits starting in older animals are most likely not idiopathic epilepsy, but one of the other causes.

There are usually 4 clear phases in a fitting animal :

  • Phase 1 - the prodromal phase : abnormal behaviour. Can last for several hours.
  • Phase 2 - the aura - a very short-lasting period of unusual behaviour just before the seizures
  • Phase 3 - the ictus or fit - uncontrollable limb movements, often the head is extended backwards, there is increased salivation, chomping of the jaws and vocalisation. Often animals lose control of their bowels and of their urinary bladder during this phase. It usually only last 2-3 minutes, but the fits can recur very rapidly inducing a state of continuous fitting (status epilepticus)
  • Phase 4 - the postictus - animals are dazed, disorientated, stagger about and show altered behaviour such as an inability to recognize familiar people during the 2-3 hours following a fit.

Careful observation of the prodromal phase is important because localised muscle twitching prior to the main seizure could indicate the presence of a local lesion within the brain, and so rule out a diagnosis of idiopathic epilepsy.

Clinical trials are currently being performed in humans on a device to alert about the onset of a fit - and this may be applicable to animals later.CLICK HERE

Prolonged fitting (status epilepticus) can result in permanent brain damage with associated changes in behaviour. Prolonged status epilepticus can be fatal.

The diagnosis of idiopathic epilepsy is based upon the clinical signs and ruling out other known causes of seizures through neurological testing, laboratory tests and special imaging techniques such as computed tomography (CT) scans and MRI scans to examine the skull and  brain.

Some authors do not advise treating animals unless they are having more than one seizure every 3 months (or 4 in a year), or if the animal is having several seizures in a session. Many animals are kept on long-term treatment, but all drugs have potential side-effects, so the frequency of treatment and drug dosage should be kept to the minimum required to control the seizure episodes. If an animal does not have a fit for 6 months it is worth trying to gradually wean it off treatment by reducing the dose by 25% each week.

Several drugs are available to control epilepsy including :


Dogs - 2mg/kg body weight twice daily by mouth. Ideally, blood phenobarbitione concentrations should be measured after 10 days treatment, and the dose of treatment modified to keep the blood concentration between 25-35mg/ml. This will control seizures in about 70% of epileptic dogs.

Cats - 1-2mg/kg body weight twice daily by mouth. In cats phenobarbitone has been reported to cause excessive thirst, increased appetite and increased frequency of urination. In addition, dermatitis, anaemia and thrombocytopenia have been reported as side-effects.


Dogs - diazepam has been used at a dose rate of 1mg/kg intravenously to control dogs in status epilepticus.

Cats - 0.25-0.5mg/kg body weight twice or three times daily by mouth has been recommended as being effective in controlling fits in some reports.. However, acute hepatic necrosis and subsequent death has been reported as a side-effect in cats.

Potassium bromide - used as a second-line drug 

Dogs - potassium bromide has been used successfully in dogs at a dose rate of 30-40 mg/kg body weight by mouth. The therapeutic serum concentration is 0.5-1.5mg/ml. 

Cats - potassium bromide has been used to treat cats with seizures at 20-30mg/kg once daily, or half the dose twice daily. It is not licensed for use.

Imepitoin - recently launched first-line drug in dogs

Advantage - do not need to run blood analyses to titrate dose. Dose range of 10 mg to 30 mg imepitoin per kg bodyweight twice daily, approximately 12 hours apart

Other drugs that have been used in dogs include : Primidone -  this is similar in it's actions to phenobarbitone, however there is a higher risk of developing liver failure; chlorazepate, valproic acid and clonazepam.

Animals on treatment should be re-examined by a veterinarian every few months to ensure that side-effects are not developing. Meticulous case recording is important to monitor on-going progress and response to treatment.

Sometimes a combination of two of the above drugs is needed to control the seizures.

If an animal is in status epilepticus the procedure is as follows :

Idiopathioc epilepsy is not curable so long term therapy is often needed.

Long term problems
If not controlled can progress to clusters of fits, status epilepticus, coma and death 

Updated January 2016