Epilepsy

Living With An Epileptic Pet by Lori S. Mohr – copyright 1992

The telltale signs are unmistakable: The eyes grow wide and bulging, the limbs tense and turn rigid, and soon after, the body begins a series of uncontrollable muscular convulsions for anywhere from a few seconds to several minutes.

Epileptic seizures are never an easy sight to witness, and they are even more distressing when it’s your dog.

According to Dr. Jeffery Glass of the Animal Kindness Veterinary Hospital in Las Vegas, Nevada, epileptic seizures and their causes are a frustrating condition in the field of animal medicine.  “When a patient comes to us after its initial attack, we perform a series of tests so that we may narrow down the field of possibilities.

“Unlike most other conditions, idiopathic epilepsy, also called primary generalized epilepsy, has no determined cause.  We have no way of knowing what might have set off the seizure until we at least run a CBC (complete blood count) and urinalysis.  Only then can we begin to speculate.”

In non-technical terms, epilepsy is a short circuit in the brain.  In technical terms, it’s a series of misfires of the neurosynaptic function that ultimately sends confused signals to the body, thus creating the uncontrolled fits.  In milder cases, a moderate amount of shaking may occur while the animal experiences a varied degree of disorientation and confusion.

RECOGNIZING THE SYMPTOMS

The episode begins with an aura.  This is the first of three distinct phases and it’s similar to the behavior a dog demonstrates just prior to a thunderstorm.  He may show signs of apprehension, anxiety or agitation shortly before the onset of the convulsions and may run to his owner for comfort or retreat to a hiding place for the duration of the attack.

The second phase, called the ictus, is the actual shaking and convulsing of the body.  On the average, this stage lasts but a moment or two but may continue for longer periods.  This is undoubtedly the most worrisome time for the panicked owners who stand watching their pet writhing uncontrollably on the floor.  At this point, if the aura wasn’t strong enough to detect the oncoming seizure, the most helpful thing to do is simply stay with and comfort the animal until the convulsions subside.

The postictal phase immediately follows the end of the seizure but may prove to be more unsettling than the ictus.  Depending upon the animal and the severity of the incident, this stage can last anywhere from a few minutes to several days.  Confusion, anxiety, blindness, disorientation, lethargy or constant pacing are signs that the animal is having a difficult time recovering from the seizure.  A veterinarian should be notified at once.

Other levels of epilepsy exist that compel the dog to exhibit uncontrolled displays of behavior such as screaming, chewing on air, aggressiveness and fear.  Some may involve a turning or twisting of only one side of the body or of the head, while others send the animal into episodes of blank staring.

For the most part, epilepsy is not a life-threatening condition.  But if the incident continues for more than a few minutes or several seizures are happening one after another, it becomes very serious.  The dog must be treated immediately or he may develop permanent brain damage or even die.

TESTING

Once the tests have been run to determine a possible triggering basis, it may be found that the dog has one of several maladies linked to the attacks.  Upon seeing the animal after the initial episode, the veterinarian will immediately run a profile and physical exam for an obvious problem.  If those produce no clue, the next series of testing could include a complete neuro exam of the brain stem function, an electroencephalogram (the EEG records activity in the brain) and a CBC (complete blood count).  These analyses will show signs of possible motives such as liver disease (cirrhosis, hepatic portal shunt), kidney disease, systemic infection, toxins (tetanus), hypoglycemia (low blood sugar), primary brain disease (tumor, meningitis), trauma, as well as a variety of nutritional deficiencies, including calcium, potassium, sodium and thiamine.

Only after all of these factors are discounted can the veterinarian come to the conclusion that the dog suffers from idiopathic epilepsy.  This is the most frustrating form for both the doctor and the patient as it is undetectable and incurable.  One small bit of encouragement is that some dogs experience only periodic episodes.  This means they happen a few times as isolated incidences and never again.  Unfortunately, this, too, cannot be diagnosed as such.

Generally, most cases begin after the age of three years but can start as early as a few months.  In the case of puppy epilepsy, it is most likely attributed to hypoglycemia.  It usually occurs after an especially active period when it has been several hours since the puppy had his last meal.  If this has been determined over the phone, the veterinarian will then suggest a solution of sugar and water to level out the blood sugar.

TREATMENT

While treatment is available to control and, in may cases, prevent further seizures, concern remains over the amount and severity of the side effects.  The accuracy of administering drugs is speculative at best, since the nature of this condition is to react in a hit-and-miss manner.  The range of dosage for each individual is very general, beginning with 1 mg per pound of body weight twice a day.  From there, the dog is monitored for number and strength of any following seizures and the medication is adjusted accordingly.  Once the animal shows positive response to the drug by exhibiting fewer, if any seizures, the current dosage is gradually cut to the least amount necessary to control reoccurring episodes.

The anticonvulsant prescribed more often than any other is Phenobarbital.  It is highly effective for generalized seizures because it is affordable and easily dispensed by pill, liquid or injection.  In addition, its side effect rating is better than the other available therapy drugs, but that doesn’t mean there aren’t any.  Since these drugs are metabolized in the liver, problems such as cirrhosis (degenerative disease of connective tissue) and necrosis (death of tissue) are a common denominator.  Monitoring by a veterinarian must be maintained throughout the entire length of the treatment.

Dr. Glass pointed out that even though these possible side effects do exist, they mostly occur when the incorrect dosage has been administered or the animal has been on long-term therapy.  Other reactions to Phenobarbital may include central nervous system depression, polyphagia (excessive eating), polydipsia (excessive thirst) and polyuria (excessive urination).

Primidone is another effective medication for controlling epileptic seizures, but the dosage is higher and more frequent.  It has the same side effects as Phenobarbital, but creates adverse reactions when certain other drugs are mixed with it.

These drugs are all fat-soluble and stay in the system longer than water-soluble drugs, which are excreted through urination, creating a factor called the half-life.  This is the time it takes for one half of the original concentration of the drug to dissipate through the body.  The half-life of Phenobarbital is varied from dog to dog but generally runs from 30 to 70 hours, considered quite a long period of time.

Phenytoin is the drug most regularly used on humans, yet it is also used with dogs.  Its half-life is only 3 to 4 hours, but the frequency is more and the dosage is considerably higher than Phenobarbital.  This creates greater costs and increased side effect risk.

Many new anticonvulsant medications are currently obtainable but are not used due to erratic or unknown dosage, insufficient research results or unknown severity of side effects.  Diazepam (Valium), while not new, is used in dogs who have other conditions that prevent them from taking any of the standard drugs.  If a known liver problem exists or at one time was treated, the veterinarian will most likely prescribe Diazepam to calm down the animal.  It is not generally considered an effective method in controlling chronic cases of epilepsy due to its mildness and short span of action.

Preventing epilepsy before it strikes, unfortunately, is not an available option unless the condition stems from head or brain injuries, contact with poisons such as lead, nutritional deficiencies or knowledge of it being hereditary.  In the case of genetics, there is no guarantee the dog will ever develop the disorder.

The number one safeguard for living with an epileptic pet is to be informed.  As with any illness, knowing how to handle it and remaining calm are the main objectives for both you and the victim.  Your veterinarian can give you printed material to help you further understand this perplexing condition and maintain a normal life with your epileptic pet.