What is Epilepsy? The word comes from a Greek word meaning "to possess, seize or hold."

Epilepsy is an abnormal discharge of nerve cells within the brain. Because the brain uses electrochemical energy, any disruption of the electrical processes in the brain may cause abnormal functioning. Unfortunately, this is what happens during epilepsy: neurons in the cerebral hemispheres misfire and create abnormal electrical activity. During epileptic seizures it is a bit like an electrical brainstorm that that causes a complete or partial loss of brain and body function. If this electrical discharge spreads throughout the brain it causes a convulsion. Epilepsy is NOT contagious and animals with epilepsy are not dangerous. There are many potential causes of seizure such as brain tumor, infection or poisoning. If an animals does not have an identifiable cause of the seizure, it is called "Idiopathic" epilepsy. Idiopathic Epilepsy is caused by a congenitally acquired tendency to have an overactive seizure focus.

Idiopathic Epilepsy is also known as Primary, genetic, inherited or true epilepsy.

With this type of epilepsy it is very hard to secure a positive diagnostic finding. There are no positive diagnostic findings that will substantiate the diagnosis. It is a case of ruling out every other possibility. Only careful breeding studies can prove that there is a family tie to the condition. It is accepted that use of breed history as well as family history may suggest a genetic basis for primary epilepsy.

Types of Epilepsy

Primary epilepsy: also known as Idiopathic, genetic, inherited, or true epilepsy.

Secondary epilepsy refers to seizures for which a cause can be determined, and there are many.

degenerative - storage diseases
developmental - hydrocephalus
toxic - lead, arsenic, organophosphates, chlorinated hydrocarbons, strychnine
infectious - encephalitis and others
metabolic - enzyme deficiency, liver or kidney failure
nutritional - thiamine, parasitism
traumatic - acute injury

Types of Seizures
The types of seizures most commonly reported are
Generalized Seizure: Tonic-clonic (may be Grand Mal or Mild):

In the Grand Mal Seizure, the tonic phase occurs as the animal falls, loses consciousness, and extends its limbs rigidly. Respiration also stops (apnea). This phase usually lasts 10-30 seconds before the clonic phase begins. Clonic movements include paddling of the limbs and/or chewing. Other signs that appear during the tonic or clonic phase are dilation of the pupils, salivation, urination, and defecation. The mild seizure involves little or no paddling or extension of limbs, and usually no loss of consciousness. Generalized seizures are usually associated with primary epilepsy.

Petit Mal Seizure (aka Absence Seizure): Depending on the authority quoted, petit mals are described as either very rare or usually unrecognized in animals. Signs are brief (seconds) duration of unconsciousness, loss of muscle tone, blank stare, and possibly upward rotation of eyes.

Partial Seizures: Movements are restricted to one area of the body, such as muscle jerking, movement of one limb, turning the head or bending the trunk to one side, or facial twitches. A partial seizure can progress to (and be mistaken for) a generalized tonic-clonic seizure, but the difference can be established by noting whether or not a seizure starts with one specific area of the body. Partial seizures are usually associated with secondary epilepsy.

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