A seizure is the result of sudden and abnormal neurological activity, basically a kind of electrical storm in the brain. In humans and dogs, seizures can manifest themselves in many ways and have a multitude of causes. However, seizures are always accompanied by altered or loss of consciousness. They may last a few seconds, several minutes, or, in the worst cases, hours. In general, seizures in dogs can be categorized into two categories: generalized and focal.
Generalized Seizures:
These seizures are sometimes referred to as “grand mal,†though this term is used less commonly in veterinary medicine than in human medicine. Generalized seizures visibly affect the entire body and are characterized by overall stiffness and/or spastic, involuntary movements. During this type of seizure, the dog typically experiences full-body rigidity along with convulsions. The dog may lose control of its bladder and/or bowels. Some dogs will vocalize. Also called “tonic/clonic†seizures, generalized seizures are the most common type of seizures seen in dogs.
Focal Seizures:
Sometimes called partial seizures, these are isolated to a particular part of the brain and therefore affect a specific part of the body. Focal seizures are typically quite mild and may simply be characterized by facial twitching. However, they can occur in another part of the body, such as a limb. Sometimes, a focal seizure will look like a fainting spell or a brief period of disorientation. In other cases, a dog experiencing this type of seizure may compulsively snap at the air (sometimes called “flybitingâ€).
Cluster Seizures:
If your dog has more than one seizure in a 24 hour period, then they are considered cluster seizures. Dogs that experience these types of seizures have a more urgent need for medical treatment than dogs with occasional seizures. Additionally, if your dog has more than three seizures in a 24 hour period, it is considered an emergency. Your dog should be seen by your primary care veterinarian or an emergency veterinarian that day. Delaying may result in increasing frequency and severity of the seizures, posing a greater threat to your dog’s health.
Status Epilepticus:
Status epilepticus is a prolonged seizure or a series of seizures that occur continuously. This is a dire emergency situation that, if untreated, can lead to brain damage, hyperthermia (elevated body temperature) and even death. Dogs in status epilepticus require hospitalization and often need to be placed on a drip of Valium (diazepam) or other drug to stop the seizures.
Phases of a Seizure:
Many seizures are preceded by a period of abnormal behavior called the pre-ictal phase. During this stage, dogs often exhibit signs of anxiety and apprehension. They may whine, pace, and/or pant. Not all dogs display pre-ictal signs, and some may only do so intermittently.The seizure itself is sometimes referred to as ictusor the ictal phase.
Following nearly every seizure is the post-ictal phase. This period may last minutes to hours and is often characterized by stupor, disorientation and/or blindness. The post-ictal phase can vary with each seizure. This phase should not be confused with the seizure itself.
Causes of Seizures:
Seizures occur for a number of reasons. In an attempt to find a cause, your vet will recommend a variety of diagnostic tests. This typically starts with blood tests, but may lead to advanced brain testing such as CT, MRI, and cerebrospinal fluid (CSF) tap. In the case of the latter, your vet might refer you to a veterinary neurologist. The following disorders may be the source of seizures in a dog:
- Structural or developmental abnormality
- Reaction to toxinor allergen
- Systemic disorder, such as liver shunt or thyroid disease
- Bacterial or viral infection
- Brain tumor (malignant or benign)
Idiopathic Epilepsy:
Epilepsy is an idiopathic disease, meaning its cause is unknown. There is no specific test to diagnose epilepsy, so advanced diagnostic tests (CT, MRI, spinal tap) are recommended in order to rule out other causes for the seizures. However, a presumptive diagnosis is sometimes made when a dog fits the criteria for epilepsy. Typical onset of epilepsy is between the ages of one to five years. Breed and family history may also play a role. Though uncommon, dogs outside of this age range may still be epileptic. Many epileptic dogs will respond quite well to drug therapy, but they usually must be on medications for life.
During the Seizure:
If you think your dog is having a seizure, try not panic. Witnessing a seizure can be emotionally traumatic and extremely stressful. It is important to know that your dog is not suffering during the seizure. In fact, he does not even realize it is happening. The best thing you can do is to remain calm and keep your dog out of danger. Move any objects that could fall on your dog or get in the way. Block off stairways and any areas that pose safety threats. NEVERput your hands or any objects in or near the mouth, as you may be seriously injured. Your dog may bite his tongue, but he will not swallow it. In general, you should steer clear of your dog until the seizure has passed, observing from a safe distance.Most seizures are not considered life-threatening. However, they do indicate a problem in the brain. If you suspect that your dog has had a seizure, contact your vet as soon as possible. Meanwhile, keep a log of seizure-like activity. Be aware that a seizure lasting more than five minutes is considered an emergency situation. It is imperative that your dog is seen by a vet immediately to prevent brain damage and hyperthermia. In addition, the occurrence of more than three seizures in a 24 hour period is also an urgent matter that requires a trip to the vet right away.
Managing Seizures in Dogs
In cases where a brain abnormality is identified, treatment options will vary based on specific diagnosis and severity of the disorder. Fortunately, seizures in epileptic dogs can often be regulated with medications and/or dietary changes. There are several anti-convulsive medications that your vet might use to prevent your dog’s seizures. Most vets will not recommend pharmaceutical treatment if the seizures occur less than once per month, or if they are very mild. As with any medication, these drugs can have side effects. However, if they help control your dog’s seizures, you may find that the benefits outweigh the risks. The following anti-convulsive medications may be prescribed by your vet to control your dog’s seizures:
- Phenobarbital
- Potassium Bromide (KBr)
- Zonisamide
- Keppra (Levetiracetam)
- Gabapentin
- Felbamate
For many dogs, there is a period of trial and error with anti-convulsive therapy. Sometimes, drugs may be combined, adjusted or switched until seizures are regulated. Never change your dog’s medications without specific instructions from your vet. It is important that you adhere to your vet’s recommendations if you want treatment to be successful.
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