By Pam Bethurum, ASCA Educational Coordinator
Canine epilepsy is characterized by "fits" or seizures. Seizures are not always hereditary. Some are the result of exposure to toxins, some are the indication of another underlying disease, and some are the result of injury. In most cases, if there is no permanent brain damage, once the dog is treated and cured of the condition, the seizures will stop. When a thorough veterinary examination and testing cannot establish why the dog is having seizures, the seizures are classified as idiopathic epilepsy. Idiopathic epilepsy is considered to be genetic.
Seizures basically are the body's reaction to a sudden, uncontrolled burst of neurologic activity in the brain. All dogs have a seizure threshold at which the neurologic activity in the brain is in a sort of balance. When the neurologic activity increases beyond the threshold, due to injury, toxins, disease or genetic predisposition, a seizure occurs. Occasionally this activity can be localized in a small area, such as the face or one leg, but usually it affects the entire body. It's like the brain suddenly sends a repeated message to all muscles in the body to contract. No two seizures are exactly alike, but can follow a general scenario as follows:
||The dog becomes nervous and agitated. Some dogs will seek out their owners, looking for reassurance because they know something is wrong. This is called the pre-ictal period.
||The dog will begin to tremble. It loses touch with it's surroundings, its eyes glaze over, it may appear blind and is unresponsive to voice commands or touch.
||The trembling will become more severe, the dog will stiffen and falls usually on its side. The dog will begin to convulse, paddling its legs. Sometimes the teeth are clenched, but the dog may salivate and open and close its jaws repeatedly. Sometimes the dog appears not to breathe. The dog may also urinate and defecate. This is called the ictal stage and usually lasts less than two minutes.
||The dog usually now begins to recover. It may pant, seem disoriented and seem blind for a period of time after the seizure. The dog may want to sleep for a long period after a seizure. This is called the post-ictal stage. It usually lasts less than an hour, but may last as long as up to two days. During this stage it is believed that gently trying to soothe and calm the dog will decrease the length and severity of this phase.
There are many conditions that can occur that resemble a seizure. A dog can develop an inner ear infection, causing it to hold its head in an odd position and lose coordination and balance. Dogs with cardiac and respiratory diseases might pant rapidly trying to compensate for lack of oxygen in the blood or can even faint, leaving them very weak, possibly even abruptly falling to the ground. Dogs even experience an odd condition called "reverse sneezing" where they will have a number of noisy, rapid, violent inspirations, during which the chest and abdominal muscles seem to spasmodically contract. Dogs, especially young puppies, will also paddle their legs, twitch and vocalize in their sleep. The main difference between these conditions and a seizure is the dog's level of consciousness. During a seizure the dog is unaware of its surroundings and cannot be aroused (as when it is asleep).
It is vital to remain calm and be sure the dog is in a safe place where it will not be injured. It is important to time the seizure and watch the dog's actions so that you can give the veterinarian the complete details of the seizure. Never put your hands near the mouth of a seizuring dog. A seizuring dog will not "swallow its tongue."
The seizures, themselves, are almost never fatal, but when they occur in clusters the dog may be prone to develop a condition called status epilepticus which is continuous, uncontrollable seizures. Continuous seizures can lead to exhaustion, hypoglycemia, hyperthermia, oxygen depletion, brain damage, and eventually death. This condition is an extreme emergency and many times the dog will need to be anesthetized in order to control the seizures.
After a complete medical workup (patient's medical history, extensive physical exam, screening bloodwork, urinalysis, and possibly spinal tap, EEG and CT scan) has revealed no medical reason for the seizure activity, a diagnosis of idiopathic (self-originated) epilepsy is made. It is also sometimes referred to as primary or true epilepsy. Generally dogs with idiopathic epilepsy have their first seizure between one and five years of age. Estrogen increases the possibility of seizures, so a female coming in season may bring on more seizures during that time. When a dog experiences more than one seizure per month, treatment with anticonvulsant drugs is usually started to help control the seizures. The drugs are not a cure and seizures are generally never eliminated completely. The therapy is an aid in reducing the frequency and severity of the seizures, bringing a better quality of life to the dog and its family. There are side effects with the drug treatment, some of which can diminish after several weeks of treatment. Treatment must be monitored and adjusted, especially during the first few weeks. Phenobarbital is one of the most widely used drugs to help control seizures. In some cases other drugs such as potassium bromide are used in combination with the Phenobarbital. Some owners of epileptic dogs have also had good success with the addition of holistic treatment with herbs such as Rescue Remedy in conjunction with the drug treatment. There is also some speculation that the seizures may be a result of allergic conditions and some vets have had success in treating dogs for allergies and controlling the seizures.
Several breeds have a real problem with epilepsy, some of which epilepsy is felt to have a genetic basis. It has been found to be quite common in German Shepherds, Belgian Tervurens, Keeshonden, Beagles, Cocker Spaniels, Golden Retrievers, Irish Setters, Labrador Retrievers, Poodles, Saint Bernards, Siberian Huskies, and Wire-haired Fox Terriers.
Epilepsy is a devastating disease. We all need to be aware that epilepsy does occur in our breed and do our best to see that it doesn't become a common problem as in some other breeds. Epilepsy is not going to go away just because we don't want to think about it. The mode of inheritance is unknown at this time, though in the Belgian Tervuren, researchers are close to identifying the gene responsible. Epileptic individuals should never be bred. Individuals producing multiple affected offspring, especially from different and unrelated mates should be taken out of your breeding program. Close relatives of affected individuals should be bred with extreme care not to cross them with lines also known to be producing epilepsy.
An organization called VetGen is currently doing research on canine epilepsy, and are willing to include the Australian Shepherd in their studies. No specific data on individual dogs will be released. They need information on affected dogs. What they need is groups of two or more closely-related affected dogs, plus two or more closely-related normal relatives. They will send kits with cheek swabs. The test is very easy to do and no vet is needed. The only expense to the owner is the postage to mail the tests back, along with pedigrees. You may contact VetGen at:
3728 Plaza Dr. , Ste.1
Ann Arbor, MI 48108
I also have several sites that I have found available on the internet with a wealth of information on epilepsy, as well as a support discussion list.
Web site for VetGen: http://www.vetgen.com/
Copyright 1999 Australian Shepherd Club of America. No reproduction of any kind without the ASCA's written permission.