Epilepsy is a recurrent seizure disorder that may be idiopathic or acquired.
Acquired epilepsy has an identifiable cause, such as a mass of scar tissue in
the brain following a head injury. Idiopathic epilepsy
occurs in up to 3 percent of dogs and accounts for 80
percent of recurrent seizures. The cause is unknown,
although an imbalance in chemicals that transmit electrical impulses in the
brain has been suggested. Seizures, usually of the grand mal type, begin
between 6 months and 5 years of age.
Breeds in which the condition is inherited include Beagles, Dachshunds,
Keeshonden German Shepherd Dogs, Belgian Tervurens, and others. Breeds with a
high incidence, but in which inheritance has not yet been established, include
Cocker Spaniels, Collies, Golden Retrievers, Labrador Retrievers, Irish
Setters, Poodles, Miniature Schnauzers, St. Bernards, Siberian Huskies, and
Wire Fox Terriers. Even mixed breeds can be afflicted with epilepsy.
As they age, our dogs often suffer a decline in functioning. Their memory, their ability to learn, their awareness and their senses of sight and hearing can all deteriorate. This deterioration can cause disturbances in their sleep-wake cycles, making them restless at night but sleepy during the day. It can increase their activity level (resulting, for example, in staring at objects, wandering aimlessly or vocalizing more) or decrease their activity level (leading to less self-care and poor appetite)...
If the diagnosis is truly epilepsy, the attacks must be recurrent and
similar. Epileptic seizures usually become more frequent with time. Your
veterinarian will ask you to keep a log of the frequency of seizures and to
provide a description of the dog’s behavior before, during, and after each
A typical epileptic seizure has three phases: an aura, a generalized grand
mal seizure, and a postseizure state-as described in the previous section. All
three phases may not be seen, because many seizures occur while the dog is
resting or asleep. Furthermore, in some cases the seizure is atypical. Instead
of a classic grand mal convulsion, the dog exhibits strange behavior such as
frenzied barking, licking or chewing at herself, staring into
space, or snapping at invisible objects. This is called a psychomotor seizure
and is believed to arise from a center lower in the brain (not the
Focal motor seizures, as already discussed, indicate a lesion in the brain.
An abnormal neurological exam or EEG during a period when there have been no
recent seizures also indicates a lesion in the brain. These findings eliminate
the diagnosis of epilepsy. Further diagnostic tests include a spinal tap with
cerebrospinal fluid analysis, skull X-rays, and a CT scan or MRI.
Treatment: A number of newer drugs are available for treating epilepsy.
However, anti-epileptic drugs, either singly or in combination, are not 100
percent effective. The best one can hope for is that treatment will
significantly decrease the number and severity of the seizures while increasing
the seizure-free interval between them. In general, treatment is indicated if
there are two or more seizures a month, or more than 10 to 12 seizures a year.
Cluster seizures and status epilepticus are other indications to start
Phenobarbital continues to be the single most effective drug for treating
epilepsy in dogs. Its principal initial side effect is sedation. Most dogs,
however, develop a tolerance to the sedative effects within a few weeks. In
some dogs, it can cause liver damage. Potassium bromide can also be
used to treat epilepsy. More dogs respond to phenobarbital than to potassium
bromide alone, but potassium bromide has no potential to cause liver damage.
Rarely, it will cause hind leg stiffness, but this is reversible if the drug is
stopped. Many dogs are best controlled by a combination of phenobarbital and
potassium bromide. A few dogs are well controlled on potassium bromide