There are two different types of
Epilepsy in dogs:
Idiopathic Epilepsy is
when there is no known cause for the condition and it is assumed it may be
an inherited condition, which is also referred to as Primary Epilepsy. Secondary
Epilepsy, when there is a specific cause for the seizures. A
veterinarian will normally run a variety of tests to rule out possible
physiological or toxic causes before diagnosing the dog as having the
idiopathic version.
Seizures are the result of muscle
responses to an abnormal nerve signal burst from the brain. They are a
symptom of an underlying neurological dysfunction.
The following tests are
advised before a diagnosis of Idiopathic/Inherited epilepsy is
made:
An epileptic seizure is the
clinical manifestation of abnormal brain activity in the cerebral cortex.
These abnormalities can create seizures that vary from the mile
“petitmal” to the generalized, full body “grand mal.”
An epileptic seizure itself can be
broken down into four stages.
- The Prodome: This stage
can last from minutes to hours or even days before the manifestation
of the actual seizure activity. This stage is typically characterized
by changes in the dog’s mood or behavior.
- The Aura: signals the
start of a seizure. Nervousness, whining, trembling, salivation,
affection, wandering, restlessness, hiding and apprehension are all
signals.
- The Ictus, the actual
seizure: A period of intense physical activity usually lasting 45
seconds to 3 minutes. The dog may lose consciousness and fall to the
ground. There may be teeth gnashing, frantic thrashing of limbs,
excessive drooling, vocalizing, paddling of feet, uncontrollable
urination and defecation.
- The Post Ictus/Ictal:
after the seizure, the dog may pace endlessly, appear blind and deaf
and eat or drink excessively.
Types of Seizures:
Mild: (Petit Mal) this can
be a simple as momentarily staring into space, or upward eye movement.
Moderate: (Grand Mal) the
dog falls down, loses consciousness and extends its limbs rigidly.
Paddling of limbs, salivation followed by possible loss of control of
bladder and bowels and vocalization (blood curdling scream) may follow.
This may occur for 1 to 3 minutes and is most often followed by a period
of restlessness, pacing, bumping into objects and loss of balance. After
the Post Ictal period the dog is conscious by may appear disoriented.
During this period great care must be taken to prevent the dog from
injuring itself.
Status Epilepticus: Can
occur as one continuous seizure lasting 10 minutes or more, or a series of
multiple seizures in a short time with no period of normal consciousness, this
may be life threatening.
Cluster Seizures: Are
multiple seizures within a 24hour period of time, may also be life
threatening. It is often difficult to distinguish between the two types
and veterinarian assistance is imperative.
Some of the physiological reasons
a dog may have secondary epilepsy are:
- Hypoglycemia or low blood sugar
- Hypothyroidism – A condition
in wh8ch the thyroid functions inadequately.
- Disease – Seizures are a
common symptom of diseases such as encephalitis and distemper.
- Lead poising – This can be
seen in dogs that like to chew on items such as painted wood.
- Brain Tumors – This is the
most common cause of seizures that begin after the age of 5.
- Hydrocephalus – The
accumulation of excess cerebrospinal fluid within the brain.
- Eclampsia – this occurs when
a lactating female’s calcium levels drop to dangerous levels.
- Toxins – Pesticides,
fertilizes, poisonous plants, arsenic, strychnine and chocolate
- Trauma – Trauma can occur
from some type of severe blow to the head such as being hit by a car,
bat, kicked or fall.
- Organ failure – End stage
liver or renal failure
- Parasitic – Severe cases of
intestinal worms, end stage heartworms or even anemia from fleas and
ticks can cause seizures.
It has been proven that epiepsy
often runs in bloodlines and new studies are showing that certain breeds
are more likely to have the disorder. Some of the breeds it occurs in more
often are Belgian Tervuerens, Beagles, Dachshuds, German Shepherds,
Keeshonds, Boxers, Cocker Spaniels, Golden Retrievers, Irish Setters,
Labrador Retrievers, Collies, schnauzers, Poodles, Dalmatians and St.
Bernards.
Just because a dog is diagnosed
with epilepsy doesn’t mean he or she can’t live a long , happy life.
In some dogs a seizure will be a one-time occurrence with no further
episodes or after effects. In other dogs, epilepsy will be an ongoing
battle for the owner and the dog.
Diet plays an important role in
the management of Canine Epilepsy. It is very important to feed a kibble
that is preservative free. Preservatives such as Ethoxyquin and BHT, BHA
should be avoided as they can cause seizures. Supermarket foods are loaded
with chemical dyes preservatives. It is best to feed you dog high
quality kibble made from human grade ingredients.
Footnotes: Overview Of Seizures
Their Causes And Treatment by Marion Mitchell
Epilepsy in dogs by Tenna Perra
Dog Owner’s Home Veterinary Handbook
First Aid Companion for Dogs & Cats