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The account accompanying my notes was written by the
owner of a Beardie who does not want to be
identified. Seizures are scary for an owner –
especially the first time – so I wanted to include a
first hand account.
A seizure is a symptom and not a diagnosis. It is
estimated that about 1% of dogs will experience a
seizure over the course of their life, and while
they are more common in certain breeds (affecting
15-20% of animals) they are relatively infrequent in
Beardies. A seizure represents a transient
paroxysmal disturbance in the electrical activity of
the gray matter, most often in the cerebral cortex
but sometimes in the thalamus, hypothalamus or
midbrain. The appearance of the seizure can reflect
the area of the brain affected. It may involve
changes in behavior, consciousness, muscle activity,
sensation or autonomic (unconscious) actions.
Behaviorally seizures can manifest as confusion,
dementia, delirium, rage or fear. Muscular changes
can produce involuntary spasms that can be rigid
(tonic) or jerky (clonic) or result in limb
paddling. The jaw may be locked or the dog may make
chewing, licking or lip smacking motions. The dog
may spin, pace or run if he remains upright. In
humans we know that seizures are often accompanied
by sensory changes, but these are harder to
appreciate in dogs. Pawing at the face, attacking
the tail or chewing and biting the flanks may
indicate changes in body sensation. Biting at
invisible flies may be a manifestation of visual
hallucination. Increased sensitivity to sounds,
light, and/or touch may be appreciated, as well as
increased sniffing suggesting increased awareness of
smells. Rapid eye movements (nystagmus) may be
noticed along with loss of balance. Increased
salivation along with uncontrolled urination and
defecation represent over-activity of the autonomic
nervous system. Rarely paroxysmal vomiting and
diarrhea will be part of the seizure.
Seizures are classified as general or partial/focal
and can be mild or severe. In mild general seizures
the dog may appear confused and have muscle tremors
– rippling skin/shaking. He may seek comfort from
his owner and reassurance may actually curtail the
seizure. Mild seizures can build into severe ones,
however. Electroencephalograms recorded during mild
seizures show symmetrical alterations in electrical
activity, while in severe ones there is massive
electrical discharge throughout the cortex. Partial
seizures show localized, asymmetrical changes and
the symptoms reflect the part of the brain
affected. In the motor cortex there will be spasms
of the face or limbs on the opposite side from the
brain activity. Partial seizures affecting the
limbic system result in outbursts of abnormal
behavior – frantic running, aggression, rage and/or
hallucinations.
Seizures can have many causes. Recurrent seizures
of no known cause are referred to as idiopathic
epilepsy. This condition is usually inherited and
is usually first seen when the dog is between one
and three years of age. However, some “idiopathic”
epilepsy is likely the result of trauma to the
brain, with seizures starting 6 to 12 months after
the injury. In dogs under 9 months of age, seizures
are often the result of congenital problems
(hydrocephalus, lissencephaly, storage disorders,
metabolic disorders, portosystemic shunt); infection
(distemper and other viral diseases, fungal,
protozoal or bacterial encephalitis); toxicity
(lead, organophosphates); trauma; hypoglycemia;
thiamine deficiency. From 9 months onwards
infection, trauma, toxicity, hypoglycemia, metabolic
disorders, and idiopathic epilepsy are joined as
potential causes by meningoencephalitis, acquired
hepatic encephalopathy (secondary to liver disease);
as well as brain cancer in older animals.
During a seizure the threshold for excitation in a
number of nerve cells in a region of the brain is
lowered either due to an increase in excitatory
neurotransmitters or reduction in inhibitory ones.
(Neurotransmitters are chemicals that transmit
nervous activity from nerve to nerve or from nerve
to muscle.) The activity of nerves is also
dependent on the concentrations of potassium,
sodium, calcium and chloride ions within and outside
the nerve. Changes in electrolyte levels can also
result in seizures. The nerve cells at the focus of
the seizure stay excited for a prolonged period and
gradually excite surrounding cells in an
increasingly larger area. This is called kindling.
Other foci of activity can also be established.
Once enough neurons are involved the seizure will be
seen. A typical seizure often has three phases: the
pre-ictal or prodromal period – sometimes called the
aura (when the dog may realize that a seizure is
coming and react in a characteristic manner), this
can last more than a day; the ictus (the actual
seizure); and the post-ictal phase (which may
include pacing, depression, drinking, eating or
sleeping, but which is characteristic for each
patient) which can continue for several days.
Between seizures most dogs appear totally normal.
Because most dogs are normal by the time they see a
veterinarian, history is most important in
evaluating seizures. A single seizure is scary to
owner and Beardie, but may never happen again, so
apart from watching to see if there are more
seizures little else needs to be done. If a dog
suddenly starts having multiple seizures within a
week, it suggests active brain disease and it would
be wise to initiate a more aggressive diagnostic
plan. Partial seizures or partial seizures that
generalize suggest a structural, localized problem –
encephalitis, tumor, injury or stroke. If the owner
notices a characteristic turn of the head, spasms,
on one side of the face or the lifting of one leg
before the seizure it suggests a localized seizure
that has generalized. Asymmetry of the signs also
suggests partial versus generalized seizures.
Partial or mild general seizures can last over 30
minutes, but partial seizures that generalize or
severe general seizures last less than five minutes
– although it can seem like hours! A video of the
seizure can provide important diagnostic
information. Changes in behavior and/or gait
between seizures indicate an active disease process
in the brain.
A thorough history will gather information about the
various body systems – respiratory,
gastrointestinal, renal, etc. – which may indicate a
systemic disease altering brain function.
Information on diet; exposure to toxins and drugs;
known traumas; similar signs in other animals in the
same household or in related animals; current
medications can all provide relevant diagnostic
data. The physical examination should include
examination of the eyes and a complete neurological
examination. Typically, testing would include a
complete blood count, fasting biochemistry profile,
thyroid profile, bile acids, serum lead and/or
cholinesterase levels (if toxicity is suspected),
urinalysis and if neoplasia is suspected chest and
abdominal X-rays. Hypothyroidism, electrolyte
imbalances, metabolic disorders and/or toxicity must
all be ruled out. If the dog is having frequent
seizures, further testing would include MRI or CT of
the brain, EEG and testing of the cerebrospinal
fluid to find the underlying cause.
If the primary cause of the seizures is discovered
treatment is directed at treating this, although
anticonvulsant therapy may be initiated while it is
brought under control, and then gradually phased
out. If a cause cannot be discovered and seizures
occur more frequently than twice a month, or in
clusters, treatment is aimed at reducing frequency
to an acceptable level. The treatment of all
underlying causes is beyond the scope of this
article. The drugs most frequently used to control
seizures are phenobarbital and/or potassium
(occasionally sodium) bromide. Phenobarbital is the
cheapest and most effective drug, but it is also
toxic to the liver, and because absorption is
variable blood levels must be carefully monitored –
the therapeutic level being close to the lethal
one. Combining the two drugs may allow lower doses
of phenobarbital to be given effectively and more
safely, as bromides have no liver toxicity. Both
drugs – given alone or in combination – can produce
a level of sedation unacceptable to the owner.
However, in general, either alone or in combination
these drugs can be used safely and effectively to
control seizures. Diazepam is too short acting in
dogs to be of value in preventing seizures, but can
be given intravenously or rectally to quickly stop
cluster seizures (status epilepticus). If these are
unchecked, loss of oxygen can cause irreparable
brain damage. Newer drugs are also being used to
treat some seizures in dogs. These include
gabapentin (Neurontin), zonisamide (Zonegran) and
levetiracetam.
Patients with seizures should be fed a balanced diet
without extra supplementation. They should avoid
chemicals and drugs which could make them more
susceptible to seizures. While clinical studies are
lacking heartworm preventatives containing
ivermectin and flea preventatives Program and
Advantage may lower seizure threshold and make
seizures more difficult to control. Organophosphate
insecticides should be avoided. Interceptor and
Frontline appear to be safer for patients with
seizure disorders.
Acupuncture can be effective in some cases,
including those that resist pharmaceutical
intervention. Valerian root is a traditional
anticonvulsant, which may be beneficial and could be
tried before turning to more potentially toxic
treatments. Milk thistle might help to protect the
liver during phenobarbital therapy.
Chances are good that you and your Beardie will
never experience a seizure. If you do, try to stay
calm and not panic.
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The bumping against the closet doors woke us up at
4:45 am on Tuesday, May 9, 2006. He was having a
generalized seizure. That’s the term they use now
for what we used to call a “grand mal” seizure. I
was terrified. Here was a Beardie lying there
salivating, urinating, paddling, jaw clenched,
breathing as if he were running, but choking at the
same time and I had no idea what to do. This lasted
about a minute. Then he calmed down and the “cool
down” period lasted another minute with his
breathing slowing, heart rate slowing and wanting to
get up. We kept him lying down until he appeared to
be back to normal. When he did get up he seemed
coherent. I snapped on his leash and rushed him to
the all-night emergency hospital. Of course, the vet
on duty sent me home to monitor him and make sure he
was ok. He was a bit unsettled and clingy over the
course of the morning.
I called my regular vet the next day and put in a
call to my good friend who is Professor Emeritus of
Veterinary Neurology. She suggested taking him to a
nearby teaching hospital for superficial
neurological tests, as well as blood work.
Everything came back “normal”. Meanwhile, my friend
gave me a “Seizure 101” Cliff Notes version of
canine seizures that night on the phone.
The advice was, just wait and see if he has another
one. He recovered just fine. I spent hours Googling
“seizures in dogs” and read mountains of material.
After awhile, the material began to repeat itself so
I felt comfortable that I was reading the right
stuff. And, of course, we scoured the yard to make
sure he had not gotten into any poison or other
chemicals and checked all of our records for yard
spraying. Shoot, we checked everything we could
think of and came up empty.
Many things can cause seizures, and many of those we
don’t even know about.
The next seizure happened in September of that
year…Monday, September 4, 2006, 4:00 am-ish as a
matter of fact. On the advice of my friend, I keep a
log of each seizure, noting day, date, time of day,
duration of seizure, symptoms, and length of
recovery time. This time, the seizure lasted a
little longer and it was stronger. Evidently, he had
thrown up first. In addition to the above things, he
gnashed his teeth and defecated. His tongue and gums
were gray. He had a secondary seizure that lasted
another minute or so, with more paddling. Afterward,
his emotions were out of whack for at least a couple
of hours. Again, he knew the seizure was coming on
because he had come flying into our bedroom at the
onset. I was calmer because I had been through this
one time before.
This time I made an appointment with a veterinary
neurologist who suggested we put him on Potassium
Bromide (KBr) to forestall any future seizures. In
addition we had a battery of blood tests done, an
MRI and joint taps, all of which came back as those
of a healthy dog. So, the decision, give KBr or not?
I opted for the medicine, against my husband’s and,
probably, many others’ wishes. He was on that for a
year and was seizure-free, but the medicine did have
side effects, one of them making him terribly hungry
or having a terribly upset stomach. During the
period he was on that medicine, we had to barricade
the kitchen to keep him from climbing on the
counters trying to find food. Luckily, the KBr
worked fine and did not have to be paired with
Phenobarbital. Three months after discontinuing the
medicine, he had another seizure.
Same drill, 5:00 am, came in and jumped on our bed.
This was, yet, worse than the ones he had before. I
reported the seizure to all of his doctors but opted
to wait and see before putting him back on KBr.
The next one came on Saturday, May 10, 2008, around
4am. Basically, it was the same as before but not,
quite so bad.
The latest seizure came Friday, September 5, 2008
around 5:30 am. This one lasted around a minute,
with a secondary seizure or, maybe a cool-down
period of a minute and a half. He woke us up
throwing up, and then he jumped on the bed to have
the seizure.
All we can do during these is steady him and try to
keep his throat clear (by keeping his head and neck
straight as possible) so he can breathe. Until the
seizures happen more frequently, he won’t go back on
medicine.
If you notice the dates, you’ll see that 4 of them
have been 2 years apart, almost to the day.
May 9, 2006
May 10, 1008
September 4, 2006
September 5, 2008
December 12, 2007
Aside from the December seizure (which was 3 months
after going off of his medicine), that tells me
something “otherworldly” is causing them, something
that science has not identified yet. People will say
I’m crazy, that statistically it’s insignificant,
but, to me, it means something. I don’t know what,
but something.
So, we have decided to live with these until they
become more frequent. I’m going to start acupuncture
treatments and just monitor him, especially around
May and September. During all of this, he was able
to continue herding sheep but did have to stop
agility when he first started KBr treatment. As the
amount of KBr tapered off, he was able to resume
agility practice again. In between seizures, we have
a perfectly normal Beardie. PON Digest extends a
grateful thank you to Linda Aronson DVM for the use
of this article which has a copyright and may
not be used without written consent.
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