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or areas involved. In dogs’, focal epileptic motor, sensory, autonomic or behavioural signs can manifest alone or in combination. Focal motor signs may include rhythmic jerks of an extremity, repeated jerking head movements, abnormal rhythmic blinking and twitching of facial musculature. Focal seizure activity believed to represent psychic and/or sensory epileptic seizure phenomena in the brain may in dogs result in a short lasting episodic change in behaviour such as e.g. anxiousness, restlessness and abnormal clinging to the owner. Focal epileptic seizures including parasympatic/epigastric components may present as hyper salivation, vomiting and dilated pupils. Dogs are as a rule unconscious when having a generalized tonic-clonic epileptic seizure. For focal epileptic seizures, it is difficult to appraise different states of consciousness as this is limited to subjective interpretation made by the person observing the dog.
If the electrical activity in the epileptic focus becomes sufficiently massive, seizure activity can spread through subcortical structures to involve more areas and eventually the entire brain, a focal seizure evolving to become generalized. In that case the initial localized seizure signs will be followed by tonic, clonic, or tonic- clonic convulsions. This is the most common seizure type observed in the dog. The onset of the focal epileptic seizure is often very short (few seconds to minutes) and the secondary generalisation with convulsions follows rapidly. The focal seizure onset may be difficult to detect due to its brief nature.
Seizure phases
The epileptic seizure is organized in phases: an ictal phase characterized by seizure activity (focal seizure activity alone, generalized seizure activity alone, or focal seizure activity evolving into generalized seizure activity manifested by convulsions) which is followed by a postictal phase. In the postictal phase, the brain restores its normal function. The postictal phase may be very short, or last for several hours to days where the animal may be disoriented, ataxic, hungry or thirsty, express a need to go in the garden or appear exhausted. Postictal blindness or aggression may also be present.
In a few dogs, the ictal phase may be preceded by a so- called prodrome, a long-term change in disposition and indicator of forthcoming seizures. Humans with prodrome may experience days of e.g. irritability, withdrawal or other emotional aberrations. In dogs the most common prodromal signs described are restlessness and attention-seeking which is known to the owner as a long- term marker of a forthcoming seizure episode.
The question of when to initiate treatment in animals with epilepsy is not an easy one. Overall, this decision is mainly influenced by seizure frequency, seizure density, severity of seizures and the owners’ opinion (as some owners are very eager to start treatment whereas others are more reluctant to do so). It is recommended by the IVETF and the ACVIM to start treatment if the animal experience >2 seizures in 6 month, experience status epilepticus or cluster seizures or experience severe (e.g. aggression) or long lasting post ictal signs.
A list of drugs which can be used for treatment of epilepsy in dogs and cats appear from table 1.
Table 1: Drugs used for treatment of epilepsy in dogs and cats
An Urban Experience

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