A transitory disturbance of the electrical activity in the brain, human or canine, gives rise to a period of abnormal muscular or behavioural activity that is termed a ‘Seizure’ or a ‘Fit’. Such abnormal electrical activity may be located in various parts of the brain and may be confined to one small area of brain tissue or be generalised throughout the cerebral cortex giving rise to differing types and severity of the ensuing seizure. A seizure may show a loss of consciousness, convulsive jerking of parts of the body, emotional disturbance or periods of mental confusion.
Conditions such as hypoglycaemia, alcoholism, brain damage or even adverse drug reactions may give rise to such seizures or fit are recurrent and have their origin in the activity of the brain tissue itself; it is referred to as Epilepsy. The term Epilepsy cover a range of conditions from mild ‘absences’, where the sufferer is merely ‘not with it’ for a brief period, to major convulsions and total loss of muscular control.

For obvious reasons human Epilepsy has bee better studied than canine Epilepsy and the human epileptic seizures of fits have been classified into three major types according to the variations in their clinical symptoms in intensity and types; these being Grand Mal, Petit Mal and Psychomotor.

In a Grand Mal type of seizure or fit there is a loss of consciousness by the patient and convulsions caused the muscular contractions. Subsequent muscular relaxation's and contractions cause violent agitation and can cause serious injuries. As the seizure subsides, the agitation results in the patient being exhausted and subsequently sleeps heavily, despite which still suffering fatigue and depression on waking. It is quite common for the patient to have no memory of experiencing the seizure.

Petit Mal is almost exclusively a childhood disorder in which, as the name implies, the seizures may be as mild as the experience or merely a sudden momentary loss or impairment of consciousness with symptoms as slight as merely upward staring eyes, a staggering gait or twitching of facial muscles. With such slight and momentary symptoms the patient may not even be aware of having suffered a seizure.

In Psychomotor Epilepsy, the main symptom is that of amnesia, there may be no loss of activity during the seizure, but the behaviour is unrelated to the environment. This type of seizure may be preceded by dizziness and, if the abnormal electrical activity originates in the temporal lobes of the brain, the perception of strange sensations, illusions, strange odours etc.

It is dangerous to draw direct parallels for canine epilepsy with these types of human epilepsy; but for those unfortunate enough to have cared for an epileptic dog subject to severe convulsions, the observations of the dog’s loss of consciousness, convulsive muscular activity, involuntary urination, defecation and ensuing exhaustion are such that it is logical to equate this type of canine seizure with the human Grand Mal type of epilepsy. The greater number of these canine Grand Mal type seizures are generally accepted as idiopathic, that is to say that no discernible organic cause, no obvious physical, haematological or biochemical abnormalities have been found to account for the seizures; this being found to hold true for canine and human epilepsy.
The short periods of loss of consciousness, the ‘absence’ of not being with it, symptoms of Petit Mal do tend to strike a familiar note with all owners of dogs; but it would be highly dubious to claim this as resembling Petit Mal type epilepsy especially considering the ease with which dogs can assume ‘convenient deafness’ or be ‘not with it’ when it suits their inclinations. As Psychomotor seizures similarly cannot be identified with any certainty in dogs, it would seem only sensible to consider that only the Grand Mall type of seizure can be definitely identified in the dog.

As over a third of human patients have a history of epilepsy Continued overleaf………………..
in their families, there is an obvious tendency for it to ‘run in families’. It is generally accepted that, in epilepsy with no identifiable organic cause, a predisposition to the disorder is assumed to be an inherited trait rather than epilepsy itself being a directly inheritable disorder.
The situation is claimed to be different in dogs, Turner (1990)* states that idiopathic epilepsy has been definitely shown to have an inherited basis in a few breeds including German Shepherds and Keeshonds and inheritance is suspected in several others such as Irish Setters, Beagles and Golden retrievers. Unfortunately Turner* does not offer any information regarding the mode of inheritance in any of his quoted breeds.

The onset of idiopathic canine epilepsy usually occurs between the ages of one and three years of age, as with humans. The treatment of the disorder is based on the use of anticonvulsant drugs, sedatives and tranquillisers. These are powerful drugs and should not be given to any dogs unless the seizures are markedly recurrent. No anticonvulsant should ever be given to a dog following only one or two isolated seizures and too high a dosage following even recurrent seizures may actually cause seizures. The choice of drug is also difficult to establish, having to balance maximum effectiveness with the minimum of acceptable side effect and the dosing regime necessary to maintain the effective level of drug in the circulation requires careful monitoring.

However, it has to be said that all is not doom and gloom for the epileptic dog or its owner, the disorder in many cases can be adequately controlled by an appropriate anticonvulsant drug therapy. The canine patient can live a relatively normal if regimented life; some have even been able to have their therapy gradually withdrawn and appeared to have been ‘cured’ as they have been able to live without further drug therapy. E. Jones. (2000)
*Veterinary Notes for Dog Owners.
(London. Popular Dogs) T Turner