Professional Reference articles are designed for health professionals to use. They are written by UK doctors and based on research evidence, UK and European Guidelines. You may find one of our health articles more useful.
Synonyms: non-epileptic attack disorder (NEAD); the use of the terms 'hysterical seizures' or 'pseudoseizures' is now considered to be inappropriate
Non-epileptic seizures (NES) is a descriptive term for a diverse group of disorders which refers to paroxysmal events that can be mistaken for epilepsy but are not due to an epileptic disorder. There are two subcategories of NES:
- Organic: includes a broad spectrum of disorders - eg, syncope, paroxysms of acute neurological insults, paroxysmal toxic phenomena, non-toxic organic hallucinosis, non-epileptic myoclonus, sleep disorders, paroxysmal movement disorders, paroxysmal endocrine disturbances and transient ischaemic attacks (TIAs).
- Psychogenic seizures include different types:
- Dissociative seizures are involuntary and happen unconsciously. This is the most common type of NES and the person has no control over the seizures.
- Associated with psychiatric conditions that cause seizures - eg, panic attacks.
- Factitious seizures - eg, Münchhausen's syndrome, fabricated or induced illness by carers.
- Psychogenic non-epileptic seizures (PNES) are the most common paroxysmal event misdiagnosed as epilepsy. They significantly affect the person's quality of life.
- The true prevalence is unknown. PNES are more common in females.
- PNES are diagnosed in at least 10-40% of the patients seen for long-term monitoring of epilepsy. Patients with PNES are often treated for epilepsy.
- Any psychological stress exceeding an individual's coping capacity often precedes PNES.
- It can be difficult to differentiate NES from epilepsy, especially as the two disorders may co-exist.
- Epileptic and non-epileptic seizures can look the same and have the same features:
- They can happen suddenly and without warning.
- They can include a loss of awareness or the person becoming unresponsive, making strange or repeated movements, or convulsing.
- They can both cause injury and urinary incontinence.
- They can both happen when awake and during sleep.
- It is essential to make a thorough assessment and ensure no further harm is caused by inappropriate diagnosis and treatment.
- Features suggesting NES include: duration over two minutes, gradual onset, fluctuating course, violent thrashing movements, side-to-side head movement, asynchronous movements, eyes closed and recall for period of unresponsiveness.
- Features suggesting epilepsy include automatisms, incontinence and biting the tongue.
Differential diagnosis of epilepsy
- Medical causes of transient neurological dysfunction (with or without loss of consciousness):
- Psychiatric disorders that may be mistaken for epilepsy: panic disorder, psychosis, attention deficit hyperactivity disorder.
- Dissociative seizures.
- Factitious disorder.
Video-electroencephalogram is widely considered to be the gold standard for diagnosing NES.
- Investigations will depend on the specific presentation of each patient. Investigations include:
- A full assessment for the presence of any underlying physical cause for epilepsy - eg, electroencephalograph (EEG), MRI brain scan.
- The EEG should not be used to exclude a diagnosis of epilepsy in a child, young person or adult in whom the clinical presentation supports a diagnosis of a non-epileptic event. Provocation by suggestion may be used in the evaluation of non-epileptic attack disorder. However, it has a limited role and may lead to false-positive results in some people..
- Investigations for physical causes of NES - eg, fasting glucose, electrolytes, ECG, echocardiogram.
- A full psychiatric assessment.
- Serum prolactin rises in over 90% of patients after a tonic-clonic seizure and 60% of patients after a complex focal seizure (previously called a complex partial seizure). However, an increased postictal prolactin is nonspecific.
A significant number of patients have mixed epileptic and non-epileptic seizure disorders. PNES are often associated with mental health problems (eg, anxiety and depression) and also personality disorders.
Where NES are suspected, suitable referral should be made to psychological or psychiatric services for further investigation and treatment.
- Management is directed at treatment of the underlying cause.
- It is essential that patients fully understand the diagnosis of non-epileptic seizures and the likely underlying causes/contributory factors. A poor reaction to the diagnosis and lack of understanding with regard to the condition and precipitating factors may lead to a poor prognosis.
- Various treatments have been tried with variable success for PNES. Treatment regimes for NES include non-psychological (eg, anti-anxiety and antidepressant medication) and psychological therapies (including cognitive behavioural therapy, hypnotherapy and paradoxical injunction therapy). With paradoxical injunction therapy, the therapist imposes a directive that places the client in a therapeutic double bind that promotes change regardless of the client's compliance with the directive.
- There is currently no reliable evidence to support the use of any treatment, including hypnosis or paradoxical injunction therapy, in the treatment of NES.
- The prognosis of organic NES will depend on the underlying cause.
- There is no strong evidence for the long-term outcome of PNES. Factors that seem to predict better outcome include relatively benign psychiatric history, more recent onset of PNES, no co-existent epilepsy, and an identifiable trauma that precedes the onset of PNES. Prognosis may also depend on the psychological aetiology of the PNES, personality characteristics of the patient, and willingness to accept the diagnosis and receive treatment.
Further reading and references
Transient loss of consciousness ('blackouts') management in adults and young people; NICE Clinical Guideline (August 2010, updated September 2014).
Epilepsy; NICE CKS, July 2019 (UK access only)
Non-epileptic seizures; Epilepsy Society
Baslet G, Seshadri A, Bermeo-Ovalle A, et al; Psychogenic Non-epileptic Seizures: An Updated Primer. Psychosomatics. 2016 Jan-Feb57(1):1-17. doi: 10.1016/j.psym.2015.10.004. Epub 2015 Oct 22.
Doss RC, LaFrance WC Jr; Psychogenic non-epileptic seizures. Epileptic Disord. 2016 Dec 118(4):337-343. doi: 10.1684/epd.2016.0873.
Devinsky O, Gazzola D, LaFrance WC Jr; Differentiating between nonepileptic and epileptic seizures. Nat Rev Neurol. 2011 Apr7(4):210-20. doi: 10.1038/nrneurol.2011.24. Epub 2011 Mar 8.
Mayor R, Smith PE, Reuber M; Management of patients with nonepileptic attack disorder in the United Kingdom: a survey of health care professionals. Epilepsy Behav. 2011 Aug21(4):402-6. Epub 2011 Jul 12.
Bodde NM, Brooks JL, Baker GA, et al; Psychogenic non-epileptic seizures--diagnostic issues: a critical review. Clin Neurol Neurosurg. 2009 Jan111(1):1-9. Epub 2008 Nov 18.
Epilepsies: diagnosis and management; NICE Clinical Guideline (October 2019)
Beghi M, Negrini PB, Perin C, et al; Psychogenic non-epileptic seizures: so-called psychiatric comorbidity and underlying defense mechanisms. Neuropsychiatr Dis Treat. 2015 Sep 3011:2519-27. doi: 10.2147/NDT.S82079. eCollection 2015.
Martlew J, Pulman J, Marson AG; Psychological and behavioural treatments for adults with non-epileptic attack disorder. Cochrane Database Syst Rev. 2014 Feb 112:CD006370. doi: 10.1002/14651858.CD006370.pub2.