Feline Seizures and Epilepsy
The intent of
this page is to provide information for people whose cats have had
seizures. Seizures are a serious problem, and a cat that has had
a seizure should be taken to a veterinarian for proper diagnosis.
A proper diagnosis may be expensive and may take some time, but
there is usually an underlying cause that can be eliminated or appropriate
treatment that can be prescribed.
The information
in this page is not meant to substitute for a veterinarian's advice,
but to aid those who are trying to learn more about their cat's
illness and to encourage owners of cats that have had seizures to
have their cat's illness diagnosed as quickly as possible. More
clinical information is available through the references at the
bottom of this article.
What is Epilepsy?
It is important to understand the difference between epilepsy and
seizures. Seizures, which range from unusual mood swings to uncontrollable
thrashing and loss of body control, are symptoms of a disease. Causes
of seizures include infections, tumors, toxic chemicals, and epilepsy.
Most seizures in cats have a cause other than epilepsy. It's most
useful to think of epilepsy as a word for seizures for which no
other cause has been found.
You will sometimes
see epilepsy divided into idiopathic, or primary, epilepsy; and
symptomatic, or secondary, epilepsy. Idiopathic epilepsy is the
term used for seizures that appear to have no other cause. Symptomatic
epilepsy refers to seizures caused by an underlying condition.
Regardless of
the terms used, the primary goal when treating a cat with seizures
is to identify the disease causing the seizures, assuming it is
epilepsy only if no other cause can be found.
General Advice
Seizures should not go untreated. There are risks of choking during
a seizure, and more importantly, the seizures may be symptomatic
of an underlying disease that can and should be treated. Anti-convulsant
drugs may be effective in controlling the seizures, depending on
the exact diagnosis.
Observing
Seizures
If you observe your cat having what you believe is a seizure, the
most important thing to do is to observe every detail you can about
it so it can be described to your vet. Frequently, your vet will
never actually be able to observe your cat having a seizure, so
your description is important to the diagnosis. Try to observe breathing
patterns; paddling, motion, or rigidness of limbs; eye dilation
or motion; salivation; body twisting; muscle twitching; and duration.
It is important to observe which parts of the body are involved.
After the seizure is over, your presence and attention will probably
comfort your cat as it regains consciousness.
Please note
that there is an incredibly wide range of symptoms associated with
seizures. Generalized convulsions are rare in cats. More common
is the "partial complex seizure," which involves an "altered
consciousness" and can involve anything from a lack of motion
to bizarre behavior such as attacking invisible objects or frantic
running and collisions with objects (yes, I know your cat does this
normally, this is why it's difficult to diagnose). The major indication
that unusual behavior is being caused by a seizure is the presence
of "features typical of seizure activity such as facial twitching,
salivation, or progression to generalized seizure." (Parent
and Quesnel, 1996)
If a cat is
having a single prolonged seizure, continuous seizures without recovery
between them, or two or more isolated seizures within 24 hours,
seek medical attention immediately. Aggressive treatment is recommended,
usually intravenous dosage of diazepam.
Diagnosis
Your close observation and careful description will help your vet
make a diagnosis. Specifically, partial motor seizures are more
indicative of symptomatic epilepsy (suggesting an underlying disease),
while idiopathic epilepsy usually causes strictly generalized seizures.
This distinction is not conclusive; it is just one piece of evidence
to be considered.
A complete physical
and neurological examination should be performed on any cat with
seizures. Blood tests should almost always be done, because they
are good at detecting many illnesses that may be causing the seizures.
Tests frequently include FeLV, toxoplasmosis, FIV, FIP, urinalysis,
complete blood cell count (CBC), and biochemical profile. If these
tests don't pinpoint the cause, your vet want to perform more tests,
or refer your cat to a internist or neurological specialist. Further
tests may include analysis of spinal fluid to detect encephalitis
and imaging procedures, such as MRI or CT, to detect lesions such
as tumors.
You should be
aware that few vets have any experience with seizures in cats. They
are rare, compared with seizures in dogs. Ask your vet questions
about what tests they are considering and what your options are.
A vet should not be offended if you get a second opinion. This is
important to remember because I have received email from owners
of several cats that have died from conditions that could have been
detected with a simple blood test and treated quite easily, but
were not. If your vet cannot find any cause of the seizures and
has not done bloodwork, you should be concerned.
Treatment
If a disease is found to be causing the seizures, the best treatment
is to remove or correct the underlying problem. The success of such
treatment depends on your vet's ability to identify and treat the
disease or remove the growth that is causing the seizures. For example,
certain kinds of tumors can be removed by surgery if caught early
enough.
If the diagnosis
is epilepsy or if the underlying disease is difficult to treat and/or
not becoming worse, then the usual therapy is to control the seizures
with anti-convulsant drugs. Phenobarbital is considered the initial
drug of choice for feline epilepsy. Diazepam (valium) may also be
effective but is more likely to cause liver problems. The dosage
must be adjusted individually to minimize side-effects. Again, this
will require your careful observation; you will want to find the
lowest dosage that will control the seizures. Potassium Bromide
is also being used to treat epilepsy, particularly in cases where
liver problems or ineffectiveness may prevent phenobarbital from
being used to eliminate the seizures.
Some people
have suggested that a taurine deficiency may cause seizures. I have
not yet seen any information based on scientific research that would
support this belief. However, it is certainly true that a cat having
seizures should be fed a balanced diet that supplies adequate taurine.
The success
of treating your cat's seizures depends on the cause of the seizures
and the cat's response to medication. This is a difficult condition
to diagnose, so it may take several trips to the vet as different
diagnostic paths are pursued. Furthermore, your vet should not be
upset if you seek a second opinion. If it is difficult to find the
cause of your cat's seizures, your local vet may refer your cat
to a veterinary internist, neurologist, or a regional teaching hospital
that may be able to pursue a wider variety of tests and treatments
and will generally be cheaper.
What You
Can Do
Take your cat to a veterinarian
The most important step is to find a good veterinarian to take care
of your cat. If your cat has had one seizure, you should call and
make an appointment. If your cat has had more than one seizure in
24 hours, find a vet IMMEDIATELY.
Learn about seizures and epilepsy
This page is a good starting point, and the links at the bottom
are excellent places to learn more about feline epilepsy.
Make sure your cat gets quality care
Ask your vet questions to see what tests are being done, what problem
they suspect and what future course of action they recommend. Feline
epilepsy is rare, so many vets are unfamiliar with it. I have received
email from people whose vets have not even done blood tests on cats
experiencing seizures and from people whose vets have just said
to monitor the behavior of a cat that was having seizures more than
once a week. In both cases, the seizures were curable, but the vet
was doing nothing to help the cat. Bloodwork should always be done,
and phenobarbital is generally prescribed when no other problem
is evident. If your vet seems unaware of how to diagnose or treat
seizures, find another vet who can. Seizures, or the disease causing
them, can be fatal if not treated properly.
Decide what your limits are
The decision of what lengths to go to is an issue between a pet
owner and veterinarians. After our vet was unable to diagnose the
cause of our cat's seizures, we were referred to a vet school. The
vet school didn't find anything in their initial tests, either,
so they asked us if we wanted to pursue an MRI or spinal fluid test.
Because of the high cost and smaller chance that a useful diagnosis
would be made from these tests, we elected not to pursue either
of these options at the time and began treatment with phenobarbital.
Since that treatment completely eliminated Shadow's seizures for
nine years, we never had a reason to reconsider these options. Shadow
eventually died of cancer unrelated to the seizures.
Follow up on the care
In some cases, your cat may be put on permanent medications. For
Shadow, this was phenobarbital twice per day. If you need to give
your cat regular medication, work it into your schedule and consider
how to handle extended absences. When we lived in apartments, we
took Shadow with us on most trips. Later we had friends and family
closer who could stop by our house twice a day to take care of him.
References
An excellent, more technical article on epilepsy is Seizure Disorders
in Dogs and Cats by R.M. Clemmons, Associate Professor of Neurology
and Neuroscience at the University of Florida.
An article that focuses on dogs, but contains a lot of good information
about epilepsy is Managing Epileptic Dogs by William B Thomas, from
the University of Tennessee.
Information on treatment of seizures with Potassium Bromide
Information on treatment with alternative medicine (mostly on trying
to avoid food allergies or vitamin deficiencies) from Dr. Susan
Wynn and Dr. Wendell Belfield
A good page from Mar Vista Animal Medical Center in California.
As canine epilepsy is a much more common and well-understood problem,
there is a great deal more information available about it on the
web. Both the Canine Epilepsy FAQ and the Epil-K9 Canine Epilepsy
Resource Center contain lots of very useful information. Although
the details concerning problems associated with specific breeds
are, of course, irrelevant, most of the information provided there
agrees with everything I've read and been told concerning feline
epilepsy (although idiopathic epilepsy is much rarer in cats than
dogs).
Parent, JM. Diagnostic approach and medical treatment of seizure
disorders. In Consultations in Feline Internal Medicine. 1997.
Parent JM, Quesnel AD. Seizures in cats. Vet Clin N Am [Small Anim
Pract]. 26:811-826,1996.
Fenner, W. R. Epilepsy. In Consultations in Feline Internal Medicine
2. edited by J. R. August. Philadelphia. W.B. Saunders Co. 1994.
pp. 437-447.
Quesnel AD. A descriptive study on feline seizure disorders [DVSc
thesis]. University of Guelph, 1994
Russo, M. E. Seizures. In Consultations in Feline Internal Medicine
1. edited by J. R. August. Philadelphia. W.B. Saunders Co. 1991.
pp. 523-526.
For other medical problems, consult the Medical Information portion
of the rec.pets.cats FAQ.
Acknowledgements
Thanks to the people who have provided information over the years
as this page has been developed. Special thanks to Joane Parent,
from the University of Guelph, who mailed me a copy of her paper
"Seizures in Cats."
Copying
and Disclaimer
This article is Copyright 1996-2003, Bruce Lowekamp. Permission
to copy, translate, or otherwise redistribute this page is granted
provided that this message remains; the URL of the original, http://www.cs.cmu.edu/People/lowekamp/feline_epilepsy.html,
is retained as the source of the article; and the copy is not made
for profit or commercial use. Any commercial or for-profit use requires
written permission.
The
author assumes no liability for the result of actions taken based
on information presented in this article. This article is not an
alternative to the advice and care of a licensed professional veterinarian.
While some of the information presented here may offer suggestions
for choosing an appropriate veterinarian, the information is definitely
not a substitute for a licensed veterinarian.
The information presented here is to inform and comfort those people
whose cat has had seizures and have taken or are about to take their
cat to a veterinarian. If you think your cat is having a health
problem, consult a licensed veterinarian!
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