Epilepsy: Causes, Types and Treatment

Epilepsy is one of the most common serious neurological conditions worldwide, affecting approximately 50 million people — about 1% of the global population. It is defined as a tendency to have recurrent, unprovoked seizures — sudden, transient episodes of abnormal electrical activity in the brain that cause changes in movement, sensation, behaviour, awareness, or consciousness.

A single seizure does not constitute epilepsy. The diagnosis of epilepsy requires either two unprovoked seizures more than 24 hours apart, or one unprovoked seizure with a high (>60%) risk of recurrence, or the diagnosis of an epilepsy syndrome.

Epilepsy is highly treatable — approximately 70% of people with epilepsy achieve good seizure control with antiseizure medication. For the 30% who do not respond adequately to medication, surgical options may offer significant benefit or even cure.

How Seizures Occur

The brain functions through the coordinated electrical activity of billions of neurons. A seizure occurs when a population of neurons fires abnormally, synchronously, and excessively, disrupting normal brain function.

Focal (partial) seizures originate from a localised region of one cerebral hemisphere — the seizure focus. Symptoms depend on the function of the brain area involved. Focal seizures may remain localised or spread to involve the entire brain (secondary generalisation).

Generalised seizures arise simultaneously from both hemispheres from the onset, typically reflecting diffuse rather than focal pathology.

Causes and Classification

By Aetiology

Structural: a visible lesion causing seizures — hippocampal sclerosis (most common structural cause; mesial temporal lobe epilepsy), brain tumours, cortical dysplasia (malformations of brain development), stroke, traumatic brain injury, post-infectious encephalitis.

Genetic: epilepsies caused by gene mutations affecting ion channels, receptors, or membrane excitability. Examples: Dravet syndrome (SCN1A mutation), KCNQ2, PRRT2. Childhood absence epilepsy and juvenile myoclonic epilepsy have strong genetic components.

Infectious: encephalitis (viral, bacterial, autoimmune), neurocysticercosis (the most common cause of acquired epilepsy in the developing world — caused by tapeworm larvae — Taenia solium — in the brain).

Metabolic: hyponatraemia, hypoglycaemia, uraemia, hepatic encephalopathy — these cause acute provoked seizures rather than epilepsy per se.

Autoimmune: anti-NMDA receptor encephalitis, LGI1 antibody encephalitis — often responsive to immunotherapy rather than antiseizure drugs.

Unknown: approximately 30% of epilepsy has no identifiable cause after full investigation.

Types of Seizures

Focal Seizures

Focal aware seizures (previously simple partial): consciousness preserved. Symptoms depend on the area of cortex involved:

• Motor cortex: rhythmic jerking of a limb (Jacksonian march)
• Temporal lobe: déjà vu, jamais vu, rising epigastric sensation, emotional changes (fear, euphoria), hallucinations (smell, taste, sound)
• Occipital lobe: visual hallucinations or loss of vision
• May be the aura (warning) before a larger seizure

Focal impaired awareness seizures (previously complex partial): consciousness altered or lost. Most commonly arise from the temporal lobe:

• Staring episode lasting 30 seconds to 2 minutes
• Automatisms — semi-purposeful repetitive behaviours (lip smacking, hand fumbling, vocalisation)
• Post-ictal confusion lasting minutes to hours
• No memory of the event

Focal to bilateral tonic-clonic seizures: a focal seizure spreads to involve both hemispheres, producing a generalised convulsion. Often mistaken for a "grand mal" seizure.

Generalised Seizures

Generalised tonic-clonic (GTC, "grand mal"): the most dramatic seizure type.

• Tonic phase: sudden loss of consciousness; body stiffens; may fall; may cry out
• Clonic phase: rhythmic jerking of limbs; tongue biting; urinary incontinence; lasts 1–3 minutes
• Post-ictal: deep sleep and confusion for minutes to hours; headache and muscle aching
• Bystanders: stay calm, protect from injury, do not put anything in mouth, turn on side (recovery position), time the seizure, call emergency services if >5 minutes

Absence seizures (petit mal): brief, sudden lapses of consciousness lasting 5–30 seconds without falling. Blank stare, sometimes with subtle eye fluttering. No post-ictal confusion. Typically begin in childhood; associated with generalised 3 Hz spike-wave discharge on EEG. Often missed — mistaken for daydreaming.

Myoclonic seizures: sudden, brief, shock-like jerks of limbs or body; typically occur in the morning shortly after waking. Characteristic of juvenile myoclonic epilepsy (JME).

Atonic seizures (drop attacks): sudden loss of muscle tone causing abrupt falls and significant injury risk; associated with severe epilepsy syndromes (Lennox-Gastaut).

Tonic seizures: sustained stiffening of limbs or body; may cause falls.

Diagnosis

History

A detailed eyewitness account of the event is indispensable — the clinician must reconstruct what actually happened during the seizure (onset, duration, movements, awareness, recovery). Key questions: any warning (aura)? Tongue biting? Incontinence? Post-ictal confusion? Family history of epilepsy? Provoking factors?

EEG (Electroencephalogram)

The EEG is the cornerstone investigation in epilepsy. Electrodes placed on the scalp record the brain's electrical activity. EEG findings in epilepsy:

• Interictal epileptiform discharges (IEDs) — spikes, sharp waves, or spike-wave complexes — reflect the epileptic focus
• Characteristic patterns: 3 Hz spike-wave in absence epilepsy; polyspike-wave in JME; temporal spikes in mesial temporal lobe epilepsy

A normal EEG does not exclude epilepsy — IEDs are absent in 50% of routine EEGs. Prolonged ambulatory EEG or video-EEG telemetry (inpatient monitoring with simultaneous EEG and video recording) increases sensitivity and allows seizure characterisation.

MRI of the Brain

High-resolution MRI is essential in all patients with new-onset epilepsy. It identifies:

• Hippocampal sclerosis — atrophy and signal change in the hippocampus; most common surgically treatable lesion
• Cortical dysplasia — abnormal cortical development; may be subtle and requires dedicated epilepsy-protocol sequences
• Brain tumours, cavernomas, gliosis, arteriovenous malformations, stroke
• MRI is normal in generalised epilepsies and many genetic epilepsies

Additional Investigations

• Blood tests: glucose, sodium, calcium, magnesium, liver and renal function; prolactin level (elevated post-ictally in tonic-clonic seizures — diagnostic aid)
• Lumbar puncture: if encephalitis, meningitis, or SAH is suspected
• Genetic testing: for specific epilepsy syndromes (SCN1A for Dravet, gene panels for childhood epileptic encephalopathies)
• Autoimmune antibody panel: NMDA-R, LGI1, CASPR2, AMPA-R, GABA-B — for autoimmune encephalitis presenting with new seizures

Treatment

Antiseizure Medications (ASMs)

The majority of people with epilepsy are treated with antiseizure medications. Drug selection depends on seizure type, epilepsy syndrome, patient age, sex, comorbidities, and drug interactions.

First-line antiseizure medications:

Drug	Indication	Mechanism	Key Points
Sodium valproate	Generalised epilepsies, JME, absence	Sodium channel / GABA	Highly effective broad-spectrum; avoid in women of childbearing age (teratogen)
Levetiracetam	Focal and generalised	SV2A modulation	Well tolerated; no drug interactions; may cause irritability/mood changes
Lamotrigine	Focal and generalised; absence	Sodium channel	Safe in pregnancy; slow titration to reduce rash risk
Carbamazepine / oxcarbazepine	Focal seizures	Sodium channel	Very effective for focal; may worsen absence/myoclonic
Ethosuximide	Absence seizures only	Calcium channel (T-type)	Drug of choice for pure absence epilepsy
Clobazam	Adjunct	GABA-A potentiation	Useful add-on; tolerance limits long-term use
Topiramate	Focal and generalised	Multiple	Also used in migraine prevention; cognitive side effects
Lacosamide	Focal	Slow inactivation of sodium channel	IV formulation available; useful adjunct

Approximately 70% of patients achieve seizure freedom with one or two medications. If two appropriate ASMs in adequate doses fail, the epilepsy is defined as drug-resistant.

Drug-Resistant Epilepsy

Approximately 30% of patients do not achieve seizure freedom with medication. These patients should be referred to a specialist epilepsy centre for:

Epilepsy surgery evaluation:
The most effective treatment for drug-resistant focal epilepsy. Comprehensive pre-surgical evaluation includes:

• Video-EEG telemetry to capture habitual seizures and localise the focus
• High-resolution epilepsy-protocol MRI
• Neuropsychological testing
• FDG-PET and SPECT (ictal perfusion studies)
• Intracranial EEG (stereoelectroencephalography — SEEG) when non-invasive evaluation is inconclusive

Surgery types:

• Temporal lobectomy / selective amygdalohippocampectomy — the most common and successful epilepsy operation; 60–70% seizure freedom in mesial temporal lobe epilepsy with hippocampal sclerosis
• Lesionectomy — removal of a cortical dysplasia, cavernoma, or low-grade tumour
• Corpus callosotomy — sectioning the connection between hemispheres; reduces drop attacks in Lennox-Gastaut; not curative but palliative
• Hemispherotomy / hemispherectomy — for catastrophic unilateral hemisphere epilepsy in children

Neuromodulation:

• Vagus nerve stimulation (VNS) — implanted device that stimulates the vagus nerve; reduces seizure frequency by >50% in approximately 50% of patients; rarely produces seizure freedom; good for palliative control
• Responsive neurostimulation (RNS) — brain-implanted device detects seizure onset and delivers counter-stimulation; for bilateral or unresectable foci
• Deep brain stimulation (DBS) — stimulation of the anterior thalamus (ANT-DBS) approved for focal drug-resistant epilepsy

Ketogenic diet — high-fat, very low-carbohydrate diet; reduces seizure frequency in approximately 50% of children with drug-resistant epilepsy; particularly effective in glucose transporter deficiency syndrome and Dravet syndrome.

Epilepsy Care in China

China's epilepsy centres offer:

• Comprehensive epilepsy evaluation: video-EEG telemetry, high-resolution 3T MRI, FDG-PET, SPECT and neuropsychological assessment
• Stereo-EEG (SEEG): intracranial depth electrode placement for refractory focal epilepsy — performed at leading centres with extensive experience
• High-volume epilepsy surgery: temporal lobectomy, lesionectomy, and hemispherotomy by specialist epilepsy neurosurgeons with outcomes comparable to international centres
• Paediatric epilepsy expertise: specialist children's epilepsy teams managing infantile spasms, Dravet syndrome, and other severe childhood epilepsy syndromes
• Ketogenic diet programmes: inpatient initiation and outpatient monitoring at tertiary centres
• Cost: care in China is generally less expensive than UK private treatment, but the hospital prices each case individually — ask us for the written quote before you commit.
• Full English care navigation from pre-surgical assessment through surgery and post-operative follow-up

Contact a ChinaMedicalTour care navigator to arrange an epilepsy assessment, surgical evaluation, or second opinion on drug-resistant epilepsy management.

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Medical content based on MSD Manuals, authored by Bola Adamolekun MD (University of Tennessee Health Science Center). Reviewed January 2024.

Frequently Asked Questions

Can overseas neurological patients have their MRI or EEG scans evaluated remotely?

Yes. Foreign neuroimaging scans, EEG recordings, and specialist consult notes can be submitted through pre-consultation coordination for detailed evaluation by Chinese cognitive neurology and movement disorder teams.

What multidisciplinary care is offered for chronic neurological conditions in China?

Tertiary neurology departments provide structured clinical assessments, cognitive battery testing, advanced biomarker diagnostics, individualized pharmacological management, and specialized neurorehabilitation planning.

How are medications and ongoing neurological care managed after returning home?

The treating medical team issues a comprehensive bilingual medical summary and prescription guidance to facilitate safe care continuity with the patient's domestic neurologist.