Seizures ‑ A
Primer
by Judy Johnstone; Goldstone Kennels
Reprinted from Giant Steps © March-April 1993
Recently, I was
reminded that even well‑meaning and knowledgeable people can have
false impressions about seizures. Many times, they are unaware of
exactly what constitutes a seizure. In this article, I will attempt
to outline the basic types of seizures and their causes. Of
necessity, this will be only a very brief overview. Your
veterinarian can answer any questions that may arise, I caution you
that I am not a veterinarian, and my information is what I have
gathered from extensive reading, and hopefully a reasonably
intelligent understanding of that material. For information on
recommended reading material, please contact me or your
veterinarian.
There are two
classifications of seizures, symptomatic and idiopathic. The
symptomatic seizures are an indication that other problems exist.
Examples of these problems are trauma, hypoglycemia, liver disease,
electrolyte disturbances, impaired circulation, and renal disease.
Idiopathic seizures are those for which no diagnostic cause can be
found ‑ those which are truly epilepsy. This one can only be
definitively diagnosed at autopsy.
The types of seizures are as follows:
Partial‑ These usually have an acquired cause and are
associated with some abnormality of movement or function localized
to a specific part of the body such as involuntary movement of an
extremity, turning the head, facial twitches, etc.
Generalized ‑ These are bilateral and are associated
with loss of consciousness, generalized motor dysfunction that is
bilateral and symmetrical, and sometimes by autonomic disturbances
including urination and defecation.
Behavioral ‑ Also called complex partial seizures.
These manifest themselves as bizarre or complex behaviors that are
repeated during each seizure. They are characterized by alterations
of thought, perception, or emotion, and can manifest themselves as
lip‑smacking, "chewing", "fly‑chasing", cowering, or hiding in
otherwise normal animals under normal circumstances. Other behaviors
that might be attributed to this type may include fits or rage,
aggression, screaming, crying, blindness, excessive salivation, and
floor‑licking. These seizures are not usually associated with loss
of consciousness, although lack of awareness may be noted.
Petitmal ‑ These are called "absence seizures" in
humans. Although they have been induced in cats, cases of this type
occurring spontaneously have not been observed in animals.
Myoclonus ‑ These are characterized by sudden massive
jerks of most muscle groups, and are extremely rare in dogs.
The components of the seizure are as follows:
Prodrome ‑ This stage is characterized by a change in
mood or behavior. Except for a change in behavior, it is impossible
to say with certainty that animals experience a prodrome.
Aura ‑ This signals the beginning of the seizure. It
is characterized by behaviors such as restlessness, nervousness,
whining, trembling, salivation, affection, wandering, hiding, or
apprehension. This stage may last from several seconds to several
days and may go unnoticed.
Ictus ‑This is the seizure stage. In the generalized
type it is characterized by a sudden increase in tone of all muscle
groups. The dog then falls, and the rhythmic or clonic phase
follows. It typically lasts from one to three minutes.
Postictus ‑ This may be the only or most significant
sign of a seizure. Confusion, disorientation, salivation, pacing,
wandering, restlessness, viciousness, unresponsiveness, and
transient blindness may be seen. This stage lasts for several
minutes to several days, during which the animal is conscious but
not functional, and may go unnoticed.
What does all this
mean? It means that most of us associate seizures with only the
generalized form. The behavioral indications may have been a real
eye‑opener for you. Also, if you read carefully, you noticed
repeated "may not be noticed" statements. This means that since our
dogs for the most part do not live attached to monitors and we do
not stay awake twenty‑four hours each day watching them, the best
any of us can say is that our dogs appear to be seizure‑free.
The wide variety of
ages at which owners have first reported a seizure activity lead us
to wonder if indeed all seizure activity is noticed, as it is simply
impossible to observe every dog every minute of every day.
Conventional wisdom
says that seizure activity is noted after exercise, during storms or
other times of stress, etc., yet I have a friend who has a Springer
who only has seizures at night while sleeping on the bed, or while
being in a crate during the day while my friend is at work. (She's
crated during the day because the other dogs attack her during her
seizures. They get crated at night while she sleeps loose.) This dog
is a tracking dog (stress) and a field dog (great excitement) and
neither of these trigger seizures.
The summary of this
is that if your dog exhibits unusual behavior at fairly consistent
intervals CHECK IT OUT!! It may be nothing, it could be an
illness‑induced problem, or it could be epilepsy. Whatever it is,
please do not remain silent. Consult with the breeder of the dog,
tell owners of any offspring or siblings, and above all do NOT use
it to criticize others, nor should you "take it personally". Only by
an open and honest sharing of information can we begin to eliminate
this unfortunate problem from our lovely dogs.
(Editor’s note: Judy Johnstone of Goldstone Kennels
is a breeder of Belgian Trevurens and Belgian Sheepdogs. We thank
her for this article.)
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