Synopsis
Diagnose functional or dissociative seizures from positive clinical evidence, protect patients from iatrogenic emergency treatment and stigma, identify coexisting epilepsy, and communicate a credible rehabilitation-focused treatment plan.
- Psychogenic non-epileptic seizures are increasingly called functional or dissociative seizures because the events are genuine, involuntary manifestations of functional neurological disorder rather than deliberate behaviour.
- Make the diagnosis from positive semiological features and specialist expertise, ideally capturing a typical habitual event on video-EEG without an epileptic ictal correlate when scalp EEG should detect one.
- Prolonged fluctuating episodes, asynchronous limb movements, tightly closed eyes, variable responsiveness and recall can support functional seizures, but no single sign is diagnostic and frontal epilepsy can be unusual.
Key red flags
A separate stereotyped brief event with lateralised onset, injury, postictal confusion or epileptiform evidence should be characterised independently rather than folded into the functional diagnosis.
Investigation priorities
Identify positive functional features and determine whether more than one event phenotype exists.
Management branches
A seizure-like event occurs in someone with suspected or documented functional seizures.
- 1. Assess airway, breathing, circulation, glucose, injury and pregnancy or new-neurology context, and compare the event with the documented habitual phenotype.
- 2. Remove hazards, cushion the head, maintain a calm low-stimulation environment, avoid restraint and painful stimulation, and observe breathing and recovery.
Key medicines
No antiseizure medicine for functional seizures aloneThere is no therapeutic antiseizure dose for functional seizures; when epilepsy has been sufficiently excluded, an epilepsy specialist should withdraw unnecessary medication gradually, usually one agent at a time on a medicine-specific schedule.
Medication for a defined comorbidityTreat depression, anxiety, migraine, pain or sleep disorder using its own evidence-based regimen and careful titration; no antidepressant or analgesic should be presented as a direct cure for functional seizures.