In accurately diagnosing a pet with epilepsy, our veterinarians rely heavily on pet-owner cooperation. The process of diagnosis requires close observation and recording of a pet’s seizure activity outside of our veterinary office, as well as observation from the vet. Epilepsy is a disease that has symptoms similar to other diseases; when possible, video and written records of episodes of seizures greatly improve accurate diagnoses, and we appreciate you actively participating in your pet’s treatment.
Epilepsy is a persistent neurological condition that is distinguished by seizures. There are several different types of seizures which are classified by the affected pet’s reaction to the episode and the brain activity patterns it causes. Seizures can be partial, secondary generalized, or generalized. Partial seizures are localized within a specific area of the brain; when a partial seizure spreads to the cortex it is considered secondary generalized. A generalized seizure is one that involves the entire cortex.
In all cases, the cause of epilepsy is difficult to determine. Some predisposing factors include bacterial/viral encephalitis, brain malformations, brain trauma, brain tumor(s), high fever, genetic and hereditary factors, metabolic disturbances, and stroke. When the onset of epilepsy can be determined, it is considered Secondary Epilepsy. If the reason for seizures cannot be established, it is referred to as Idiopathic Epilepsy.
Cluster: numerous seizures within a short span of time, allowing very short periods of consciousness between each seizure.
Complex partial: involves behaviors that are continually repeated throughout the seizure. In otherwise normal pets these behaviors include biting, chewing, hiding, vocal noises, running. Seizure side effects can also include biting oneself, diarrhea, temporary blindness, and vomiting.
Partial: seizure-like jerking movement limited to specific areas of the body. (i.e. localized muscle spasms, facial twitches).
Petit mal: there are several different indications of a petit mal seizure and all do not necessarily occur at once. Some pets shake their head left and right for a few minutes: others’ entire bodies shake throughout the extent of the seizure. Some pets blankly stare with a glazed look while others continuously blink while arching their backs.
Status epilepticus: life-threatening emergency of a continuous seizure lasting longer than 30 minutes, or a series of multiple seizures in a short time without periods of consciousness in between.
Tonic-clonic: a pet typically falls over, losing consciousness and extending its limbs to a rigid outstretched position. Breathing stops for a short period of 10-30 seconds until the convulsing movements begin which can include chewing or making a paddling motion with the limbs. Some dogs exhibit dilated pupils, excessive drooling, and incontinence.
Prodome – preceding a seizure (hours to days) a pet’s mood/behavior might begin subtly changing from its normal essence.
Pre-ictal phase – marks the beginning stages of the seizure and can include constant salivation, nervousness, trembling, or whining. It can last seconds to hours.
Ictal phase – the actual seizure. Most last from a few seconds to a few minutes and are characterized by tensed muscles and partial paralysis. Some pets lose control of their salivary glands and bowels.
Post-ictal Phase – the post-seizure period in which the dog is still disoriented, confused, and possibly dehydrated or salivating. Some pets also experience temporary blindness and wander aimlessly.
Once a thorough neurological examination has been completed (accompanied by necessary blood tests) and epilepsy has been diagnosed, it is typically controlled with medication. The veterinarian will decide which medication is best for your pet based on their species and breed. In more severe cases epilepsy can be treated with surgery, but surgical options will be determined by the veterinarian for those particular cases. If your pet’s seizures are severe enough to be placed on a medication, common anti-seizure medications for pets can include the following:
Clorazepate – A relatively mild anticonvulsant that is also used to treat anxiety and phobias in canines and felines. Side effects include tiredness, increased appetite, and lack of coordination.
Diazepam – An extremely fast acting anticonvulsant typically used to treat status epilepticus. Side effects include hypotension, hypoventilation, and impaired consciousness.
Felbamate – Highly effective in controlling partial seizures with little-to-no side effects when used as the only anticonvulsant in a treatment plan. Side effects are limited in reported case studies due to the drug’s short half-life.
Levetiracetam – Can be used singularly or combined with a Phenobarbital or Potassium Bromide and is one of the newer anti-seizure medications for pets. Must be administered three times per day. So far, the most common side effect is that some pets develop a tolerance for it, thus losing its effectiveness.
Phenobarbital – Most commonly prescribed anti-seizure medication. Side effects can include increased appetite, dehydration, frequent urination, lethargy, or ataxia.
Potassium Bromide – Can be used singularly or in addition to Phenobarbital and is the second most prescribed anticonvulsant. The commonly reported side effects are increased appetite, dehydration, frequent urination, lethargy, or ataxia (involuntary muscle movements).
Primidone – Similar to Phenobarbital in effectiveness, but has a greater risk of causing liver disease so is only prescribed when Phenobarbital proves ineffective. Side effects can include agitation, anxiety, ataxia, dehydration, depression, frequent urination, increased appetite, or lethargy.
Zonisamide – Used to treat generalized seizures in canines but it is not commonly prescribed as it is very expensive. The most common side effects are ataxia (involuntary muscle movements), nausea, and tiredness.
If you think your pet may have had a seizure, the first step is to remain calm and keep your voice mellow and soothing in an effort to prevent the seizure from reoccurring. Show your pet love and affection, allowing them to understand that they have done nothing wrong and that everything will be okay. Please contact our office immediately so we can complete a full pet evaluation to ensure there are no pressing health issues that require emergency medical attention. It is important to remember that epilepsy treatment is not curative and is only meant to help prevent seizures from occurring; though a pet can relapse, and they can still occur.
If you think your pet may have epilepsy or have questions about the disease, please contact our office.