Seizures and Epilepsy in Cavalier King Charles Spaniels: What Science Says About Diagnosis, Treatment, and Care in Oregon

A seizure can be frightening to witness, especially when it happens to a beloved Cavalier King Charles Spaniel. The good news is that veterinary medicine has clear steps for identifying seizure disorders, distinguishing them from look-alike conditions, and protecting your companion’s quality of life.

For families researching a Cavalier King Charles Spaniel in Oregon, understanding breed-specific health concerns is an important part of responsible ownership. This guide explains what current science says about seizures, idiopathic epilepsy, diagnosis, treatment, emergency care, and life with a therapy-temperament dog.

Important: This article is educational and does not replace an examination by your veterinarian. Any first-time seizure should be discussed with a veterinary professional.

How common are seizures in Cavaliers?

Cavalier King Charles Spaniels appear to have a higher seizure burden than the general dog population.

In a large United Kingdom primary-care study, Cavaliers had a one-year seizure prevalence of 6.95%, representing 112 cases among 10,143 dogs. The estimated prevalence across all breeds was approximately 0.82%.[1] This does not mean that every Cavalier will develop epilepsy, but it does support careful observation and proactive veterinary care.

Epilepsy was also identified among common disorders recorded in Cavaliers in another primary-care study by O’Neill and colleagues.[2]

A more recent high-field MRI study reported a median age at first seizure of approximately 40 months among Cavaliers with normal neurological examinations between seizures.[3] That age is a research finding, not a rule. Seizures can begin earlier or later, and age at onset helps your veterinarian decide how broad the diagnostic workup should be.

What is idiopathic epilepsy?

A seizure is caused by abnormal, excessive electrical activity in the brain. Idiopathic epilepsy is diagnosed when a dog has recurrent, unprovoked seizures but testing does not identify a structural, metabolic, toxic, or infectious cause.

The word “idiopathic” means that the underlying cause is not detectable with current testing. It does not necessarily mean there is no genetic contribution. The International Veterinary Epilepsy Task Force notes that epilepsy genetics are complex and still under investigation.[4]

At this time, there is no single confirmed genetic epilepsy locus or validated DNA test for idiopathic epilepsy in Cavalier King Charles Spaniels. Responsible breeding decisions therefore rely on health histories, veterinary evaluation, family information, and ongoing research rather than one definitive epilepsy screening test.

Important Cavalier look-alikes

Not every unusual movement is an epileptic seizure. Cavaliers can experience other neurological or movement disorders that may appear similar:

• Episodic Falling (EF): A distinct movement disorder associated with variants in the BCAN gene. A DNA test is available for EF, but this test does not diagnose idiopathic epilepsy.[5]

• Dry Eye Curly Coat Syndrome (DECCS): A separate inherited condition associated with a FAM83H mutation.[5]

• Myoclonus: Brief, shock-like muscle jerks that can be confused with focal seizures.

• Syncope: Fainting or collapse related to reduced blood flow to the brain, sometimes associated with heart disease.

• Chiari-like malformation and syringomyelia: Breed-associated structural conditions that may cause pain, scratching, altered movement, or paroxysmal episodes.

• Ventriculomegaly and other brain abnormalities: Structural findings that may be relevant when seizures occur.

Because these conditions require different management, careful differentiation matters. A phone video of an episode can be one of the most useful tools you bring to your veterinarian.

Seizure signs to watch for

Seizures do not always look like dramatic full-body convulsions.

Generalized seizures may include:

• Sudden collapse or loss of awareness

• Stiffening followed by paddling movements

• Drooling or foaming

• Vocalization

• Urination or defecation

• Confusion, restlessness, or sleepiness afterward

Focal seizures may include:

• Facial twitching

• Repetitive chewing or swallowing

• Staring or sudden changes in awareness

• Fly-biting or snapping at invisible objects

• Abnormal movements affecting one side or one body area

The recovery period is called the post-ictal phase. Your Cavalier may seem confused, unsteady, hungry, restless, or temporarily disoriented. Keep your companion in a quiet, safe area while the brain returns to normal function.

How veterinarians diagnose epilepsy

Idiopathic epilepsy is a diagnosis of exclusion. Your veterinarian will first work to rule out other explanations.

1. Begin with a detailed history

Record:

• Your Cavalier’s age at the first episode

• Date, time, and duration of each event

• What happened before, during, and after the episode

• Possible toxin, medication, or supplement exposure

• Whether your dog fully recovered between events

• Any pain, scratching, balance changes, or behavior changes

• Known family history of seizures or neurological disease

A seizure diary and clear video can help distinguish epilepsy from syncope, EF, myoclonus, or pain-related episodes.

2. Complete baseline testing

Your primary veterinarian may recommend:

• Physical examination

• Neurological examination after the post-ictal period

• Complete blood count

• Serum biochemistry panel

• Urinalysis

• Liver function testing or bile acids when indicated

These tests can identify conditions such as liver disease, kidney disease, abnormal glucose, electrolyte disturbances, or other systemic problems.

3. Consider referral and advanced diagnostics

MRI is the best available imaging method for evaluating many structural brain and spinal conditions. Cerebrospinal fluid analysis may also be recommended when inflammation, infection, or another central nervous system disorder is suspected.

Advanced testing is especially important when:

• Seizures begin before 6 months or after 6 years of age

• Your Cavalier has an abnormal neurological examination between episodes

• Clusters or status epilepticus occur

• Seizures continue despite appropriate medication

• Pain, scratching, balance problems, or other neurological signs are present

In Cavaliers, MRI may help evaluate structural conditions such as Chiari-like malformation, syringomyelia, ventriculomegaly, or other changes that should not be automatically labeled idiopathic epilepsy.

When is treatment recommended?

The 2015 American College of Veterinary Internal Medicine consensus statement recommends discussing long-term antiseizure treatment when a dog has:

1. Two or more seizures within six months

2. Cluster seizures or status epilepticus

3. Severe or prolonged post-ictal signs

4. Seizures that are becoming more frequent or severe

5. A structural or metabolic cause requiring ongoing management

Treatment goals are realistic: reduce seizure frequency and severity, limit emergencies, minimize medication side effects, and protect quality of life.

Common medication options

• Phenobarbital: A frequently used first-line medication. It requires periodic blood concentration checks and serum biochemistry monitoring. Liver monitoring is commonly performed about every six months, or more often when clinically indicated.

• Imepitoin: Supported as a first-line option in the ACVIM consensus statement and used in some countries. Availability and prescribing practices vary, particularly in the United States.

• Levetiracetam: Often well tolerated and primarily cleared through the kidneys, giving it a wide safety margin in many dogs.

• Potassium bromide, zonisamide, and other medications: May be used alone or in combination depending on seizure pattern, test results, kidney and liver health, cost, and side effects.

Never change or stop seizure medication suddenly unless your veterinarian directs you to do so. Your veterinarian may adjust treatment based on your dog’s seizure diary, medication levels, laboratory results, and day-to-day comfort.

Seizure first aid: What to do at home

During a seizure, your calm and practical response can help keep your furry friend safe.

1. Start a timer. Note the exact time the seizure begins.

2. Remove hazards. Move furniture, sharp objects, and other pets away if you can do so safely.

3. Do not put anything in your dog’s mouth. Cavaliers cannot swallow their tongues, and you could be bitten accidentally.

4. Keep your hands away from the face. Do not restrain the movements.

5. Reduce stimulation. Dim lights, lower noise, and keep children at a safe distance.

6. Record a video if possible. Only do this if you can do so without endangering yourself or your dog.

7. Monitor recovery. Keep your Cavalier in a secure, quiet space during the post-ictal period.

Seek emergency veterinary care immediately if a seizure lasts more than five minutes, if seizures occur in a cluster, or if your companion does not regain normal awareness between seizures. The 2023 ACVIM consensus statement considers these situations medical emergencies.[7]

Veterinary neurology options in the Portland metro area

Families in Boring, Portland, and throughout the PNW can ask their primary veterinarian about referral options. Available services can change, so confirm current availability, referral requirements, hours, and emergency instructions before traveling.

• DoveLewis Emergency Animal Hospital in Portland offers board-certified veterinary neurology and neurosurgery, 24/7 emergency support, and an on-site 3T MRI.

• VCA Northwest Veterinary Specialists in Clackamas lists neurology, diagnostic imaging, and emergency and critical care services.

• Pacific Northwest Pet ER & Specialty Center serves Vancouver, Portland, Camas, and surrounding communities, with neurology appointments, specialty referrals, and on-site CT and MRI services.

Bring medical records, laboratory results, medication details, seizure videos, and your written timeline to a neurology consultation. Preparation can make the diagnostic process more efficient and less stressful for your family member.

Can a Cavalier with epilepsy live a fulfilling life?

Often, yes: but each dog’s outlook is individual. Research on caregiver-reported quality of life suggests that seizure frequency and medication side effects, rather than seizure severity alone, strongly influence how families assess daily wellbeing.[8]

A seizure diagnosis may change a therapy dog’s plans. A Cavalier with uncontrolled seizures may not be safe in busy healthcare, school, or community settings, and therapy programs may have their own health and participation standards. However, a diagnosis does not automatically erase your companion’s therapy-like temperament or ability to provide affection and comfort at home. With veterinary guidance, some dogs can continue enjoying gentle routines, family companionship, enrichment, and appropriate social activities.

At Green Acres Nextgen Cavaliers in Boring, Oregon, we believe health, temperament, and responsible lifelong care belong together. Whether you are caring for a puppy, an adult companion, or focusing on senior dog health, early detection and regular veterinary checkups give your Cavalier the best opportunity for comfort and joyful days.

A seizure disorder can require patience, organization, and ongoing care, but it does not define your dog. With a thoughtful treatment plan and an observant, devoted owner, many Cavaliers continue sharing cherished memories, countless quiet moments, and a rewarding bond with their families.

Sources and bibliography

1. Kearsley-Fleet, L., et al. “Prevalence and Risk Factors for Canine Epilepsy of Unknown Origin in the UK Primary Care Population.” Journal of Veterinary Internal Medicine, 2018. doi:10.1111/jvim.15290

2. O’Neill, D. G., et al. “Epidemiology of Disease in Cavalier King Charles Spaniels under Primary Veterinary Care in the UK.” Canine Genetics and Epidemiology, 2015. doi:10.1186/s40575-015-0016-7

3. “Clinical Characteristics and High-Field MRI Findings in Cavalier King Charles Spaniels with Seizures.” Frontiers in Veterinary Science, 2024/2025. doi:10.3389/fvets.2024.1507861

4. De Risio, L., et al. “International Veterinary Epilepsy Task Force Consensus Proposal: Diagnostic Approach to Epilepsy in Dogs.” BMC Veterinary Research, 2015. doi:10.1186/s12917-015-0463-0

5. Gill, J. L., et al. “A Canine BCAN Gene Mutation Is Associated with Episodic Falling Syndrome in Cavalier King Charles Spaniels.” PLoS Genetics, 2012. doi:10.1371/journal.pgen.1002462

6. Podell, M., et al. “2015 ACVIM Small Animal Consensus Statement on Seizure Management in Dogs.” Journal of Veterinary Internal Medicine, 2016. doi:10.1111/jvim.13841

7. Charalambous, M., et al. “ACVIM Consensus Statement on the Management of Status Epilepticus and Cluster Seizures in Dogs and Cats.” Journal of Veterinary Internal Medicine, 2023. doi:10.1111/jvim.16928

8. “Quality of Life in Dogs with Epilepsy: A Pilot Study.” Frontiers in Veterinary Science, 2022. doi:10.3389/fvets.2022.1107315

9. Cornell University Riney Canine Health Center. “Idiopathic Epilepsy in Dogs.” Updated April 2025.

10. DoveLewis Emergency Animal Hospital. “Veterinary Neurology.”

11. VCA Northwest Veterinary Specialists. “Specialty Veterinary Care in Clackamas, Oregon.”

12. Pacific Northwest Pet ER & Specialty Center. “Emergency and Specialty Veterinary Care.”