See also separate article Managing Epilepsy in Primary Care.
An epileptic seizure is the transient occurrence of signs or symptoms due to abnormal electrical activity in the brain, leading to a disturbance of consciousness, behaviour, emotion, motor function or sensation. Epilepsy is characterised by the occurrence of at least two unprovoked episodes of periodic disturbance in neurological function. Epilepsy is not a single diagnosis but is a symptom with many underlying causes.
The diagnosis of epilepsy in adults should be established by a specialist medical practitioner with training and expertise in epilepsy. Epileptic seizures and epilepsy syndromes should be classified according to the description of seizure, the seizure type, the epilepsy syndrome and the aetiology. The seizure type(s) and epilepsy syndrome, aetiology, and comorbidity should be accurately determined, because failure to classify the epilepsy syndrome correctly can lead to inappropriate treatment and persistence of seizures. A wrong diagnosis of epilepsy can cause severe restrictions on a patient's lifestyle as well as unnecessarily side-effects from long-term medication.
Seizures can be classified as being:
- Generalised seizures: associated with impairment of consciousness and distortion of the electrical activity of the whole or a large part of both sides of the brain. May be tonic-clonic (the term generalised tonic-clonic is now preferred to grand mal), isolated tonic or clonic, myoclonic (brief, shock-like muscle contractions) or absence (petit mal).
- Partial seizures (focal is now preferred to partial): originate within networks limited to one hemisphere, discretely localised or more widely distributed. They may be divided into simple partial (motor or sensory) with retained awareness or complex partial (impaired awareness). Partial seizures may progress into generalised seizures. See separate article covering Temporal Lobe Epilepsy.
- There are a number of other forms of epilepsy, especially in children. See separate article Epilepsy in Children and Young People for further information.
- Approximately a third of people with epilepsy in the UK have an anatomically-identifiable cause (symptomatic epilepsy), eg cerebrovascular disease, cerebral tumour, head injury. This is the most common cause of epilepsy occurring in the elderly - see separate article Epilepsy in Elderly People.
Patients with learning disabilities
- Diagnosis of epilepsy in patients with learning difficulties can be difficult. Confusion may arise between stereotypical or other behaviours and seizure activity.
- Particular attention should be paid to the possibility of adverse cognitive and behavioural effects of anti-epileptic drug (AED) therapy.
- All adults with epilepsy and learning disabilities should have a risk assessment, eg bathing and showering, preparing food, using electrical equipment, the suitability of independent living.
- The prevalence of active epilepsy is 5-10 cases per 1,000 - but with 5-30% of these misdiagnosed as having epilepsy.
- Epilepsy most commonly starts in children or in people older than 60 years of age.
- Epilepsy is much more common in people with a learning disability.
- Epilepsy is a feature of over 200 genetic disorders, accounting for approximately 2% of people with epilepsy. Approximately 30% of people with epilepsy have a first-degree relative with the condition.
Causes of epilepsy
- Most are idiopathic; seizures due to underlying diseases affecting the brain are more likely to have a focal onset.
- Cerebrovascular disease such as cerebral infarction, cerebral haemorrhage, and venous thrombosis.
- Head injury: head trauma is more significant when it occurs with loss of consciousness lasting longer than 30 minutes, post-traumatic amnesia lasting longer than 30 minutes, focal neurological findings, or neuro-imaging findings suggesting a structural brain injury.
- Following cranial surgery.
- CNS infections such as meningitis or encephalitis.
- Neurodegenerative diseases: epilepsy is more common in people with Alzheimer's disease or multi-infarct dementia.
- Autoimmune disease.
- Brain neoplasm.
- Genetic diseases.
- Drugs: for example, phenothiazines, isoniazid, tricyclic antidepressants; binge alcohol drinking; drug (eg benzodiazepines) or alcohol withdrawal.
- Metabolic medical disorders such as uraemia, hypoglycaemia, hyponatraemia, hypernatraemia, hypercalcaemia and hypocalcaemia.
Accurate history-taking is essential with particular reference to an eyewitness if possible. It must include family history, past medical history, medication history as well as alcohol and illicit drugs.
- Generalised seizures cause a disturbance in consciousness.
- The classic generalised tonic-clonic seizure progresses through tonic, clonic and postictal phases. The postictal phase is often associated with headache and drowsiness. Generalised tonic-clonic seizures are often associated with tongue-biting and incontinence.
- Whatever the cause, the patient may have amnesia for both the event and its exact circumstances.
- Petit mal seizures cause an interruption to mental activity for less than 30 seconds. They rarely persist into adulthood.
- Complex focal seizures may have features of:
- Motor: automatism, lip-smacking, plucking at clothes, hair.
- Sensory: transient paraesthesiae.
- Autonomic: odd epigastric sensation, nausea, abnormal taste or smell.
- Psychiatric: unreality, déjà vu, fear.
- There may be a clear precipitating cause, eg inadequate sleep, alcohol abuse or medications such as tricyclic antidepressants, which lower the seizure threshold.
- It is common for seizure frequency to vary throughout the menstrual cycle. In ovulatory cycles, peaks occur around the time of ovulation and in the few days before menstruation. In anovulatory cycles, there is an increase in seizures during the second half of the menstrual cycle.
- Possible seizure-related symptoms include:
- Sudden falls.
- Involuntary jerky movements of limbs whilst awake.
- Blank spells.
- Unexplained incontinence of urine with loss of awareness, or in sleep.
- Odd events occurring in sleep, eg fall from bed, jerky movements, automatisms.
- Episodes of confused behaviour with impaired awareness.
- Possible simple partial seizures.
- Epigastric fullness sensation.
- Déjà vu.
- Elation, depression.
- Depersonalisation, derealisation.
- Inability to understand or express language (written or spoken).
- Loss of memory, disorientation.
- Olfactory, gustatory, visual, auditory hallucinations.
- Focal motor or somatosensory deficit, or positive symptoms (jerking, tingling).
- Examination is usually unremarkable.
- Check for any neurological or cerebrovascular signs.
- Skin examination may reveal café-au-lait spots (neurofibromatosis), port-wine stain (Sturge-Weber syndrome) or adenoma sebaceum (tuberous sclerosis).
Sudden unexpected death in epilepsy (SUDEP)
- Epilepsy-related causes of death account for 40% of mortality in persons with epilepsy and include:
- Death due to an underlying neurological disorder.
- SUDEP, which is defined as sudden, unexpected, non-traumatic, non-drowning death in an individual with epilepsy, witnessed or unwitnessed, in which postmortem examination does not reveal an anatomical or toxicological cause for the death.
- Accidents during an epileptic attack.
- Status epilepticus.
- Treatment-related death.
- Sudden unexpected death in epilepsy (SUDEP) is the most common cause of death directly related to epilepsy, and most frequently occurs in people with chronic epilepsy.
- Information provided to people with epilepsy and carers should take account of the small but definite risk of SUDEP.
- SUDEP seems to occur more commonly during sleep and more often affects young adults with medically intractable epilepsy (especially tonic-clonic seizures), those with neurological comorbidity, and patients receiving antiepileptic drug polytherapy.
- The risk of SUDEP can be minimised by optimising seizure control and being aware of the potential consequences of nocturnal seizures.
- Cardiac arrhythmias.
- Transient ischaemic attack.
- Paroxysmal vertigo.
- Metabolic disorders, hypoglycaemia.
- Acute encephalopathy.
- Drop attacks.
- Sleep disorders: narcolepsy, sleep apnoea, parasomnias.
- Transient global amnesia.
- Involuntary movement disorder.
- Panic attacks.
- Hysterical fugue.
- Aggressive outbursts, eg related to learning disability.
- Non-epileptic seizures.
- An EEG should be performed only to support a diagnosis of epilepsy when the clinical history suggests that the seizure is likely to be epileptic in origin. The EEG should not be used in isolation to make a diagnosis of epilepsy.
- If an EEG is considered necessary, it should be performed after the second epileptic seizure but may, in certain circumstances, as evaluated by the specialist, be considered after a first epileptic seizure. Following a first unprovoked seizure, unequivocal epileptiform activity shown on EEG can be used to assess the risk of seizure recurrence.
- Photic stimulation and hyperventilation should remain part of standard EEG assessment but the patient should be made aware that such activation procedures may induce a seizure.
- An EEG should not be performed in the case of probable syncope because of the possibility of a false-positive result.
- An EEG may be used to help to determine seizure type and epilepsy syndrome.
- Repeated standard EEGs may be helpful when the diagnosis of the epilepsy or the syndrome is unclear. However, if the diagnosis has been established, repeat EEGs are not likely to be helpful. Repeated standard EEGs should not be used in preference to sleep or sleep-deprived EEGs.
- When a standard EEG has not contributed to diagnosis or classification, a sleep EEG should be performed.
- Long-term video or ambulatory EEG may be used in the assessment when there are diagnostic difficulties after clinical assessment and standard EEG.
- Neuroimaging should be used to identify structural abnormalities that cause certain epilepsies. MRI is the imaging investigation of choice. MRI is particularly important in those:
- Who have any suggestion of a focal onset on history, examination or EEG (unless clear evidence of benign focal epilepsy).
- In whom seizures continue in spite of first-line medication.
- Neuroimaging should not be routinely requested when a diagnosis of idiopathic generalised epilepsy has been made.
- CT should be used to identify underlying gross pathology if MRI is not available or is contra-indicated. CT may be used to determine whether a seizure has been caused by an acute neurological lesion or illness.
- Other tests:
- Appropriate blood tests (eg glucose, electrolytes, calcium, renal function, liver function, and urine biochemistry) to identify potential causes and/or to identify any significant comorbidity should be considered.
- A 12-lead ECG should be performed in adults with suspected epilepsy. In cases of diagnostic uncertainty, a referral to a cardiologist should be considered.
Neuropsychological assessment should be considered when it is important to evaluate learning disabilities and cognitive dysfunction, particularly in regard to language and memory. Referral for a neuropsychological assessment is indicated:
- When the person with epilepsy is having educational or occupational difficulties.
- When an MRI has identified abnormalities in cognitively important brain regions.
- When there are reported memory or other cognitive deficits, and/or cognitive decline.
- All adults with epilepsy should have a comprehensive care plan, which should include lifestyle issues as well as medical issues.
- Epilepsy specialist nurses (ESNs) should be an integral part of the network of care.
- A Cochrane review found that two types of intervention (ESNs and self-management education) showed some evidence of benefit; there was no clear evidence that other service models substantially improved outcomes for adults with epilepsy.
- The anti-epileptic drug (AED) treatment strategy should be individualised according to the seizure type, epilepsy syndrome, co-medication and comorbidity, lifestyle, and the preferences of the person and their family and/or carers as appropriate.
- The diagnosis of epilepsy needs to be critically evaluated if events continue despite an optimal dose of a first-line AED.
- Consistent supply to the adult with epilepsy of a particular manufacturer's AED preparation is recommended. Different preparations of some AEDs may vary in bioavailability or pharmacokinetic profiles.
- Treatment should be with a single AED wherever possible. If the initial treatment is unsuccessful, then monotherapy using another drug can be tried.
- If an AED has failed because of adverse effects or continued seizures, a second drug should be started and built up to an adequate or maximum tolerated dose and then the first drug should be tapered off slowly.
- Combination therapy should only be considered when attempts at monotherapy with AEDs have not resulted in seizure freedom. If trials of combination therapy do not bring about worthwhile benefits, treatment should revert to the regimen (monotherapy or combination therapy) that has proved most acceptable.
- If using carbamazepine, offer controlled-release carbamazepine preparations.
- Epilepsy is resistant to drug treatment in a third of patients. Of the newer drugs, the broad-spectrum AEDs levetiracetam, topiramate, and zonisamide have multiple mechanisms of action and are often chosen in drug-resistant epilepsy.
Initiation of drug treatment
- AED therapy should only be started once the diagnosis of epilepsy is confirmed, except in exceptional circumstances. AED therapy should be initiated by a specialist.
- Treatment with AED therapy is generally recommended after a second epileptic seizure. AED therapy should be considered and discussed after a first unprovoked seizure if:
- There is a neurological deficit.
- The EEG shows unequivocal epileptic activity.
- The patient considers the risk of having a further seizure unacceptable.
- Brain imaging shows a structural abnormality.
Continuation of drug treatment
- Maintain a high level of vigilance for adverse effects of treatment.
- Continuing AED therapy should be planned by a specialist but part of an agreed treatment plan and the needs of the patient and their family and/or carers as appropriate should be taken into account.
- If management is straightforward, continuing AED therapy can be prescribed in primary care if local circumstances and/or licensing allow.
- Adherence to treatment can be optimised with the following:
- Educating patients and their families and/or carers in the understanding of their condition and the rationale of treatment.
- Reducing the stigma associated with the condition.
- Using simple medication regimens.
- Positive relationships between healthcare professionals, the adult with epilepsy and their family and/or carers.
- Regular blood test monitoring is not recommended as routine, and should be done only if clinically indicated. Indications for monitoring of AED blood levels are:
- Detection of non-adherence to the prescribed medication.
- Suspected toxicity.
- Adjustment of phenytoin dose.
- Management of pharmacokinetic interactions (eg changes in bioavailability, changes in elimination, and co-medication with interacting drugs).
- Specific clinical conditions, eg status epilepticus, organ failure and certain situations in pregnancy.
- Examples of blood tests include:
- Before surgery - clotting studies in those on sodium valproate.
- FBC, electrolytes, liver enzymes, vitamin D levels, and other tests of bone metabolism (eg serum calcium and alkaline phosphatase) every 2-5 years for patients taking enzyme-inducing drugs.
- Asymptomatic minor abnormalities in test results are not necessarily an indication for changes in medication.
Withdrawal of drug treatment
- The decision to continue or withdraw medication should be taken after a full discussion of the risks and benefits of continuing or withdrawing AED therapy. Withdrawal of AEDs must be managed by, or be under the guidance of, the specialist.
- The risks and benefits of continuing or withdrawing AED therapy should be discussed when the person with epilepsy has been seizure-free for at least two years.
- Withdrawal of AED treatment should be carried out slowly (at least 2-3 months) and one drug should be withdrawn at a time.
- Particular care should be taken when withdrawing benzodiazepines and barbiturates (may take up to six months or longer) because of the possibility of drug-related withdrawal symptoms and/or seizure recurrence.
- There should be an agreed plan that if seizures recur, the last dose reduction is reversed and medical advice is sought.
- Psychological interventions have not been proven to affect seizure frequency and are not an alternative to pharmacological treatment.
- Psychological interventions (relaxation, cognitive behavioural therapy, biofeedback) may be used in conjunction with AED therapy in patients when seizure control is inadequate with optimal AED therapy.
- Adults with epilepsy should have a regular structured review and be registered with a general medical practice.
- Adults with epilepsy should have a regular structured review with their GP, but depending on the person's wishes, circumstances and epilepsy, the review may be carried out by the specialist.
- The maximum interval between reviews should be one year but the frequency of review will be determined by the patient's epilepsy and their wishes. The interval is usually between 3 and 12 months.
- Treatment should be reviewed at regular intervals to ensure that the patient is not maintained for long periods on treatment that is ineffective or poorly tolerated and that concordance with prescribed medication is maintained.
- Annual review should include an enquiry about side-effects and a discussion of the treatment plan to ensure concordance and adherence to medication.
- At the review, there should be access to written and visual information, counselling services, information about voluntary organisations, epilepsy specialist nurses, appropriate investigations, and referral to tertiary services, including surgery, when indicated.
Referral for complex or refractory epilepsy
- If seizures are not controlled, there is diagnostic uncertainty or there is treatment failure, adults with epilepsy should be referred to tertiary services soon for further assessment. Referral should be considered when one or more of the following criteria are present:
- The epilepsy is not controlled with medication within two years.
- Management is unsuccessful after two drugs.
- A patient experiences, or is at risk of, unacceptable side-effects from medication.
- There is a unilateral structural lesion.
- There is psychological and/or psychiatric comorbidity.
- There is diagnostic doubt as to the nature of the seizures and/or seizure syndrome.
- Behavioural or developmental regression or inability to identify the epilepsy syndrome should result in immediate referral to tertiary services.
- Patients with specific syndromes such as Sturge-Weber syndrome, the hemispheric syndromes, Rasmussen's encephalitis and hypothalamic hamartoma should be referred to a tertiary epilepsy service.
- Psychiatric comorbidity and/or negative baseline investigations should not be a contra-indication for referral to a tertiary service.
Vagus nerve stimulation (VNS) and deep brain stimulation (DBS)
- VNS is indicated for use as an adjunctive therapy in reducing the frequency of seizures in adults who are refractory to anti-epileptic medication but who are not suitable for resective surgery. This includes adults whose epileptic disorder is dominated by focal seizures (with or without secondary generalisation) or generalised seizures.
- The National Institute for Health and Clinical Excellence (NICE) states that the evidence on the efficacy of DBS for refractory epilepsy is limited and that there are potentially serious side-effects. Therefore, DBS is currently not recommended.
The introduction of newer AEDs with better tolerability and fewer drug-drug interactions has made a significant impact on the treatment of epilepsy. However a significant proportion of patients still have intractable epilepsy. Surgery is increasingly used as treatment for refractory focal epilepsy.
- Modern techniques for the accurate localisation of epileptic discharge and the recognition of specific seizure patterns have increased the role of surgery in the management of drug-resistant epilepsy.
- Neurosurgical treatment has particular benefit for selected people with refractory focal epilepsy.
- Surgical operations for epilepsy include anteromedial temporal resection (the most frequently performed operation for medial temporal lobe epilepsy), corpus callosotomy (for generalised epilepsy syndromes), functional hemispherectomy and multiple subpial transection.
Epileptic attacks are the most frequent medical cause of collapse at the wheel. If within a 24-hour period more than 1 epileptic attack occurs, these are treated as a 'single event' for the purpose of applying the epilepsy regulations. Epilepsy includes all events: major, minor and auras.
- Any patient should be advised to stop driving and notify the Driver and Vehicle Licensing Agency (DVLA) and their motor insurance company following a seizure.
- Group 1 (private car or motorcycle):
- A person who has suffered an epileptic attack whilst awake must refrain from driving for at least 1 year from the date of the attack before a driving licence may be issued.
- A person who has suffered an attack whilst asleep must also refrain from driving for at least 1 year from the date of the attack. However, if they have had an attack whilst asleep more than three years previously and have had no attacks whilst awake since that original attack whilst asleep, then they may be licensed even though attacks whilst asleep may continue to occur. If an attack whilst awake subsequently occurs, then must refrain from driving for at least 1 year from the date of the attack.
- The person must comply with advised treatment and check-ups for epilepsy, and the driving of a vehicle by such a person should not be likely to cause danger to the public.
- Group 2 (large goods vehicle - LGV, or passenger carrying vehicle - PCV):
- During the period of 10 years immediately preceding the date when the licence is granted, the applicant/licence holder should:
- be free from any epileptic attack, and
- have not taken medication to treat epilepsy, and
- not otherwise be a source of danger whilst driving.
The following regulations also apply:
- Group 1: provided a licence holder/applicant is able to satisfy the regulations (see above), a 3-year licence will be issued normally. A 'Till 70' licence is restored if seizure-free for 5 years since the last attack, with medication if necessary in the absence of any other disqualifying condition.
- Group 2: regulations require a driver to remain seizure-free for 10 years since the last attack, without anticonvulsant medication.
- Following first unprovoked epileptic seizure or solitary fit:
- Group 1: 6 months off driving from the date of the seizure unless there are clinical factors or investigation results which suggest an unacceptably high risk of a further seizure, ie 20% or greater per annum.
- Group 2: 5 years off driving from the date of the seizure if the licence holder has undergone recent assessment by a neurologist and there are no clinical factors or investigation results (eg. EEG, brain scan) which indicate that the risk of a further seizure is greater than 2% per annum. They should have taken no anti-epilepsy medication throughout the 5-year period immediately prior to the granting of the licence.
- Accidents resulting from a seizure often cause injuries, eg head injuries, lacerations, fractures and burns.
- Depression and anxiety disorders are more common in people with epilepsy.
- Studies have suggested that women with epilepsy are at increased risk of fractures, osteoporosis and osteomalacia.
- Sudden unexpected death in epilepsy (SUDEP): sudden death without any identifiable cause in a person with epilepsy accounts for approximately 500 deaths each year. The risk is increased with increasing frequency and severity of seizures. Death may also occur during status epilepticus.
- Remission becomes less likely with longer persistence of seizures.
- Factors suggesting a poorer prognosis include a combination of complex partial and tonic-clonic seizures, clustering of seizures, abnormal physical signs, and the presence of learning difficulties.
Further reading & references
- Transient loss of consciousness in adults and young people, NICE Clinical Guideline (August 2010)
- British National Formulary; 62nd Edition (Sep 2011) British Medical Association and Royal Pharmaceutical Society of Great Britain, London
- Epilepsy Action
- Epilepsy Society
- Epilepsy Scotland
- Epilepsy Wales
- Epilepsy, Prodigy (June 2009)
- Nunes VD, Sawyer L, Neilson J, et al; Diagnosis and management of the epilepsies in adults and children: summary of BMJ. 2012 Jan 26;344:e281. doi: 10.1136/bmj.e281.
- Epilepsy, NICE Clinical Guideline (January 2012)
- Crawford PM; Managing epilepsy in women of childbearing age. Drug Saf. 2009;32(4):293-307. doi: 10.2165/00002018-200932040-00004.
- Nouri S et al, Sudden Unexpected Death in Epilepsy, Medscape, May 2011
- Surges R, Thijs RD, Tan HL, et al; Sudden unexpected death in epilepsy: risk factors and potential pathomechanisms. Nat Rev Neurol. 2009 Sep;5(9):492-504. Epub 2009 Aug 11.
- Asadi-Pooya AA, Sperling MR; Clinical Features of Sudden Unexpected Death in Epilepsy. J Clin Neurophysiol. 2009 Aug 24.
- Bradley PM, Lindsay B; Care delivery and self-management strategies for adults with epilepsy. Cochrane Database Syst Rev. 2008 Jan 23;(1):CD006244.
- Kwan P, Schachter SC, Brodie MJ; Drug-resistant epilepsy. N Engl J Med. 2011 Sep 8;365(10):919-26.
- Brodie MJ, Kwan P; Newer drugs for focal epilepsy in adults. BMJ. 2012 Jan 26;344:e345. doi: 10.1136/bmj.e345.
- Ramaratnam S, Baker GA, Goldstein LH; Psychological treatments for epilepsy. Cochrane Database Syst Rev. 2008 Jul 16;(3):CD002029.
- Deep brain stimulation for refractory epilepsy, NICE Interventional Procedure Guideline (January 2012)
- Passaro EA, Identification of Potential Epilepsy Surgery Candidates, Medscape, May 2011
- de Tisi J, Bell GS, Peacock JL, et al; The long-term outcome of adult epilepsy surgery, patterns of seizure remission, Lancet. 2011 Oct 15;378(9800):1388-95.
- Balabanov A, Rossi MA; Epilepsy surgery and vagal nerve stimulation: what all neurologists should know. Semin Neurol. 2008 Jul;28(3):355-63. Epub 2008 Jul 24.
- Rossetti AO, Hurwitz S, Logroscino G, et al; Prognosis of status epilepticus: role of aetiology, age, and consciousness J Neurol Neurosurg Psychiatry. 2006 May;77(5):611-5.
- Kraemer DL et al, Epilepsy Surgery, Medscape, Nov 2011
- At a Glance Guide to the Current Medical Standards of Fitness to Drive, Driver and Vehicle Licensing Agency
|Original Author: Dr Colin Tidy||Current Version: Dr Colin Tidy||Peer Reviewer: Dr John Cox|
|Last Checked: 14/03/2012||Document ID: 2107 Version: 24||© EMIS|
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