Functional Seizures vs. Epileptic Seizures: Understanding the Difference
Watching someone experience a seizure—or having one yourself—can be frightening. Shaking, loss of awareness, and difficulty responding can leave patients and families searching for answers. When a clinician explains that the episodes are functional seizures rather than epileptic seizures, the terminology may raise new questions.
Both types of seizures are real and involuntary. Understanding the distinction helps guide diagnosis, treatment, and a plan for staying safe (Gilmour et al., 2020). link.springer.com
What Are Epileptic Seizures?
Epileptic seizures occur because of abnormal electrical activity in the brain. Depending on the brain regions involved, symptoms may include changes in awareness, unusual sensations, staring, repetitive movements, stiffening, or shaking. A person does not have to fall or convulse to experience an epileptic seizure.
Epilepsy is a brain disorder associated with a continuing tendency to have epileptic seizures. However, not every epileptic seizure means a person has epilepsy; some occur in connection with an acute medical problem. Diagnosis requires consideration of the circumstances and medical history (National Institute of Neurological Disorders and Stroke [NINDS], n.d.). National Institute of Neurological Disorders …
What Are Functional Seizures?
Functional seizures are episodes involving changes in awareness, movement, or responsiveness that are not caused by the epileptic electrical activity responsible for epileptic seizures. They are a presentation of functional neurological symptom disorder (FNSD), formerly known as functional neurological disorder (FND).
You may also hear the terms dissociative seizures or psychogenic nonepileptic seizures (PNES). Episodes can involve shaking, collapse, staring, or periods of unresponsiveness. They reflect a disruption in nervous system functioning and are not deliberately produced (Gilmour et al., 2020; Stone, n.d.).
An episode can occur without an obvious emotional trigger. The absence of a clear stressor does not make the symptoms less legitimate (Stone, n.d.). link.springer.com
Why Can They Be Difficult to Tell Apart?
Functional and epileptic seizures can look similar, even to healthcare professionals. No single outward feature gives a family member a reliable way to diagnose an episode. Specialists consider the overall pattern, what happens before and afterward, and the results of appropriate testing (Stone, n.d.). Functional Neurological Disorder (FND)
Witness descriptions and recordings of typical episodes can help a neurologist. Recording should never take priority over protecting the person from injury.
How Is the Diagnosis Made?
Assessment generally includes a detailed history, information from witnesses when available, and review of the episodes’ characteristics. Other explanations, such as fainting, may also need evaluation.
When feasible, video-electroencephalography (video-EEG) can record a typical episode while simultaneously measuring brain electrical activity. Interpreted alongside the history and observed features, it is the gold standard for a documented functional seizure diagnosis. When recording an episode is not feasible, specialists may use other evidence and explain the level of diagnostic certainty (American Academy of Neurology [AAN], 2025). aanfiles.blob.core.windows.net
A normal routine EEG alone does not establish functional seizures or rule out epilepsy. Clinicians must interpret the recording in context; even during an event, the clinical features matter rather than simply whether an EEG appears normal (Stone, n.d.). Functional Neurological Disorder (FND)
Can Someone Have Both Conditions?
Yes. Functional seizures and epilepsy can coexist. Identifying one does not automatically exclude the other. When someone experiences different kinds of episodes, the treatment team needs to determine which are functional, which are epileptic, and how to respond to each (Gilmour et al., 2020). link.springer.com
This is one reason to tell your neurologist about episodes that look or feel different from your usual pattern.
Why Treatment Differs
Treatment for epilepsy often includes antiseizure medication. Other options may be considered depending on the epilepsy type and individual circumstances (NINDS, n.d.). National Institute of Neurological Disorders …
Functional seizures require a different approach. Care may include an understandable diagnostic explanation, psychological treatment tailored to functional seizures, and attention to associated symptoms and coexisting conditions. Psychological interventions may improve seizure frequency, quality of life, and functioning, although benefits vary and the evidence has limitations (AAN, 2025). aanfiles.blob.core.windows.net
A psychotherapy referral does not mean symptoms are imagined. Stress and trauma may be relevant for some people, but they are not required for an FND diagnosis. Treatment should reflect the individual’s history and needs (Gilmour et al., 2020). link.springer.com
Antiseizure medications do not treat functional seizures themselves. They may still be needed for coexisting epilepsy or another medical indication. Do not stop or change prescribed medication on your own; any reduction should be directed by the prescribing clinician (AAN, 2025). aanfiles.blob.core.windows.net
Responding Safely to an Episode
For someone with established functional seizures, ask the treating team for a written action plan explaining how to respond to typical episodes and when emergency evaluation is needed (AAN, 2025). aanfiles.blob.core.windows.net
General seizure first aid includes staying with the person, clearing nearby hazards, timing the episode, and gently positioning them on their side when appropriate. Do not restrain their movements or put anything in their mouth.
For a first or undiagnosed seizure, call 911. General emergency warning signs also include an episode lasting more than five minutes, repeated seizures without recovery, breathing difficulties, significant injury, or an episode in water. A known functional seizure diagnosis should never be used to dismiss a new or medically concerning event (Centers for Disease Control and Prevention [CDC], 2024). CDC
Questions to Ask Your Treatment Team
- What evidence supports my diagnosis?
- Have all my different episode types been evaluated?
- Could I have both functional seizures and epilepsy?
- Which treatments are intended for which symptoms?
- What should my family do during a typical episode?
- What changes should prompt urgent medical attention?
Finding Support
A clear diagnosis can help you move toward care that fits your needs. You deserve an explanation that takes your symptoms seriously and gives you room to ask questions.
Support for patients with FNSD can include addressing the emotional impact of symptoms, navigating uncertainty, and working toward meaningful daily goals alongside appropriate neurological care.
Contact me today for a free 15 min consultation.
Dan Powell, MA., LMFT, BCBA
References
American Academy of Neurology. (2025). Management of functional seizures practice guideline: Clinician summary. https://aanfiles.blob.core.windows.net/guidelines/2cceae40-edcf-484d-9054-bbdf76206bca/25_FunctionalSeizure-ClinGL_v03b.pdf
Centers for Disease Control and Prevention. (2024, May 15). First aid for seizures. https://www.cdc.gov/epilepsy/first-aid-for-seizures/
Gilmour, G. S., Nielsen, G., Teodoro, T., Yogarajah, M., Coebergh, J. A., Dilley, M. D., Martino, D., & Edwards, M. J. (2020). Management of functional neurological disorder. Journal of Neurology, 267(7), 2164–2172. https://doi.org/10.1007/s00415-020-09772-w
National Institute of Neurological Disorders and Stroke. (n.d.). Epilepsy and seizures. https://www.ninds.nih.gov/health-information/disorders/epilepsy-and-seizures
Stone, J. (n.d.). Functional (dissociative) seizures. Neurosymptoms. https://neurosymptoms.org/en/symptoms/fnd-symptoms/functional-dissociative-seizures/
