Some breeds of dogs are more likely to have cluster seizures that are difficult to explain. Even a careful examination by a vet may not turn up any obvious physical problems. In such cases, typical seizure medications such as phenobarbital may not be effective.
Cluster seizures may occur because of an issue in the brain such as a tumor that interrupts communication between the parts of the brain or a lack of oxygen within the brain. Seizures can also result from low glucose levels in the blood or a thyroid deficiency. Poisoning can also bring on seizures.
Seizures may also happen with no apparent cause, which is called idiopathic epilepsy --- though the vet is unable to find anything wrong with the animal, the seizures still occur. In this case, it is presumed to be an inherited condition. German shepherds are susceptible to seizures, as are cocker spaniels, border collies, boxers, dachshunds, beagles, labrador retrievers and golden retrievers, all of whom have a tendency towards inheriting the condition. If the seizures have a genetic basis, they can arise when the dog is a puppy around 6 months old or manifest later in life. Most German Shepherds with idiopathic epilepsy experience their first seizure between the ages of one and five years.
Symptoms of Cluster Seizures
A generalized seizure starts with a sudden collapse, followed by abnormal movement of limbs; there may also be drooling, vomiting, uncontrolled urination, or defecation. The dog is unconscious, unresponsive and unable to control the spasms. Between seizures, the dog may be quiet, disoriented, or stagger and act drunk.
Aftercare for Seizures
Note down all the things your dog did to see if you can find a trigger for the seizure and jot down the frequency. Let him rest after -- dim the lights and eliminate any loud sounds. Usually, seizures don’t last more than 1 minute; however, if they last more than 5, this is considered a medical emergency and requires immediate veterinary intervention for intravenous anticonvulsants to avoid irreversible brain damage or death. If there are 3 or more seizures in a 24 hours period or the pet does not fully recover between seizures, this is also an emergency. Each seizure will make subsequent seizures more likely, so it is important you get to the veterinarian so they can stop the cycle with anti-seizure medications.
Full blood work including a glucose test is necessary for cluster seizures as well as an assessment of thyroid function. Poisoning should also be investigated. If those tests don't result in a diagnosis, the vet may proceed with a CT scan or an MRI to look for brain tumors or lesions.
Treatment for Seizures
In addition to phenobarbital, seizures can also be prevented and controlled with leviteracetam, zonisamide, or potassium bromide.