Seizures & Your Pet

Definition

Seizures have specific characteristics according to if they are
generalized or partial. Generalized Seizures

There is whole body involvement with some or all of the
following signs: loss of consciousness (the pet is unaware of
its surroundings and doesn’t respond to its name when called),
loss of control of the legs (collapse or involuntary twitching
or jerking of the legs), loss of control of the head (clamping
motions of jaw), and loss of control of bladder and rectum
(urination and/or defecation).

Partial seizures

There is partial body involvement with either involuntary head
or leg movements or sometimes, abrupt behavioral changes.

The seizure itself is often followed by a period of
disorientation that may last a few minutes to several hours.

Other episodes that can look like seizures are fainting spells
associated with heart disease and/or arryhthmias or sleep
disorders.

Causes

Causes of seizures can originate from the brain (intracranial)
or outside the brain (extracranial).

Intracranial causes

Epilepsy (recurring seizures in a young to middle aged dog or
cat after other causes have been ruled out), trauma, migrating
parasites, viral infections, bacterial infections,
immune-mediated diseases, tumors

Extracranial causes

Low blood sugar levels (hypoglycemia); common in small breed
puppies, poorly regulated diabetic cats, and dogs with
pancreatic tumors (insulinomas)

Low calcium levels (hypocalcemia); can occur in small breed
pregnant dogs or shortly after birthing, or hyperthyroid cats
that recently have undergone surgery

Toxicities with organ dysfunction: liver, kidney

Ingested toxins: snail bait (metaldehyde), antifreeze (ethylene
glycol), lead, insecticides, rodenticides (strychnine,
bromethalin),

Diagnosis

Complete blood panel including chemistries can rule out most
extracranial causes. If these are normal, the problem is most
likely originating from the brain. The brain, unfortunately, is
inaccessible to easily performed tests.

Other tests

Tests to assess brain function and structure are often invasive,
costly, require special equipment and must be done under general
anesthesia. These procedures include: CSF taps (sample of the
cerebral spinal fluid) to evaluate for inflammation or
infection; EEG (electroencephalogram) to assess brain wave
activity; magnetic resonance imaging (MRI) and computed
tomography (CT) scans are used to check for masses such as
tumors, abscesses or other lesions.

Because of the difficulty involved with completely assessing the
brain, the diagnosis of epilepsy is often based on normal blood
results, an animal’s age, breed, and a recurrent pattern of
seizures. Depending on the frequency and/or intensity of the
seizures, your veterinarian may recommend medical treatment to
control them. While the goal of treatment is to abolish seizures
completely, this may not be feasible. But often the frequency
and intensity can be lessened to allow the pet to have a good
quality of life. Treatment is usually life long.

Treatment

If seizures are associated with a specific cause (hypoglycemia,
hypocalcemia), this is addressed.

If epilepsy is diagnosed, treatment options include:

Monitoring without treatment

If the seizures happen infrequently (1-6 times a year) and
aren’t long lasting, some owners opt for their animals “to live
with it” rather than giving daily medication. Ideally, you
should keep track of the frequency and duration of your animal’s
seizures, and your veterinarian should be contacted if the
frequency, duration and/or intensity of the seizures increases.

Medications

Regardless of the type of medication chosen to control your
pet’s seizures, it is important you stay in close contact with
your veterinarian with the goal of minimizing the seizures.
These drugs can be used at a low doses initially, but increasing
the dose and/or adding on other drugs may be necessary if
seizures persist. Any changes in drug dosages and/or frequencies
of administration should only be done on the advice of your
veterinarian.

* Phenobarbital

This may be obtained from your veterinarian or through an
outside pharmacy.

 It must be given 2 times daily; the dosage is adjusted
according to if the seizures are controlled.

 This medication will cause increased thirst, increased
urine output, hunger and sometimes weight gain. Drowsiness is
common when first starting the medication.

 Since it is metabolized by the liver, elevation in
liver enzymes is common.

 Care must be taken when other drugs are given to a
patient on phenobarbital since negative drug – drug interactions
can occur.

* Potassium Bromide

This medication can be obtained only through some, but not all,
outside pharmacies.

 It is given 1-2 times daily in the form of a compounded
liquid or pill. The dosage and frequency is adjusted according
to if the seizures are controlled. When given once daily, it is
usually given in the evening.

 Since the liquid is bitter tasting, it is recommended
to give it with food.

 This medication will occasionally cause drowsiness when
first started.

* Valium (diazepam)- This medication can be obtained through any
outside pharmacy.

 This drug alone usually can not effectively manage
seizure patients for long term control. Given as needed, it is
useful for short term control of seizures when it is given
immediately orally when a pet is recovering from a seizure. This
is to prevent yet another seizure from occurring (“clustering”).

 A few dogs will have such intense seizures that they
may necessitate administration of injectable valium (given
rectally via syringe), given by the owners at home.

Management

If no seizures have occurred for a year or more, sometimes the
drug doses are decreased. This should only be done after
consulting with your veterinarian.

If seizures persist, the medication must be continued, and the
dosage is often increased or combined with another medication.
This should only be done after consulting with your veterinarian

Drug blood levels and panels and monitoring

Doing general blood panels, especially to evaluate liver enzymes
while on phenobarbital treatment, and electrolytes when on
potassium bromide treatment, are important in monitoring your
pet’s overall health. These are recommended at least yearly.
These can be done at any time in relation to time of
administration of the drugs.

Measurements of drug levels of phenobarbital and potassium
bromide are usually done within 6-8 weeks of starting these
medications. It is recommended to test levels yearly and
following a change in dosing.

These are timed tests so that it is important when scheduling
appointments for measurement of drug levels, it is correlated
with when the medication was administered.

Phenobarbital levels are done within 10-12 hours post pilling
and potassium bromide levels are checked just prior to the time
when the pet normally receives the medication. There are no
blood levels done to evaluate valium levels.

When your pet does have a seizure, stay calm and provide a quiet
environment (dim the lights and avoid loud noises). Do not put
your fingers in its mouth. Note the duration and intensity of
the seizure and contact your veterinarian.

If you have questions regarding this disease and its treatment,
do not hesitate to contact your veterinarian.

The above is general veterinary information. Do not begin
any course of treatment without consulting your regular
veterinarian. All animals should be examined at least once every
12 months.