Epilepsy
Seizure disorders — diagnosis, antiepileptic prescribing and monitoring
Epilepsy is one of the most common serious neurological conditions in the UK, affecting around 600,000 people. It is characterised by a tendency to have recurrent, unprovoked seizures caused by abnormal electrical activity in the brain. With the right diagnosis and treatment, around 70% of people with epilepsy can achieve good seizure control.
What is Epilepsy?
Epilepsy is defined as a disorder of the brain characterised by an enduring predisposition to generate epileptic seizures, and by the neurobiological, cognitive, psychological and social consequences of this condition. A diagnosis requires at least two unprovoked seizures occurring more than 24 hours apart, or one unprovoked seizure with a high risk of recurrence. Epilepsy has many causes including genetic factors, structural brain abnormalities (such as cortical dysplasia or hippocampal sclerosis), infection, head injury, and metabolic disorders. In many cases, no cause is found — this is idiopathic or cryptogenic epilepsy.
Types of Seizures
Seizures are classified by how they begin and their clinical features. Focal seizures originate in a network limited to one brain hemisphere — they may be aware (previously called simple partial) or impaired awareness (previously called complex partial). Generalised seizures involve networks across both hemispheres from onset. Tonic-clonic seizures (previously grand mal) involve a stiffening phase (tonic) followed by rhythmic jerking (clonic) and are often accompanied by tongue biting, incontinence, and post-ictal confusion. Absence seizures cause brief staring spells lasting 5–30 seconds with sudden onset and offset — common in childhood. Myoclonic seizures are brief, shock-like jerks. Atonic seizures cause sudden loss of muscle tone. Correct seizure classification is essential to guide antiepileptic drug (AED) choice, as some drugs can worsen certain seizure types.
Diagnosis (NICE NG217)
Diagnosis is primarily clinical, based on a detailed description of the event from the patient and a witness. Key investigations include EEG (electroencephalogram) — standard or sleep-deprived — to detect epileptiform activity; and MRI brain (preferred over CT) to identify structural causes. According to NICE NG217, all adults and children with a suspected first seizure should be seen urgently by an epilepsy specialist (within 2 weeks). The clinical history should include onset, aura, duration, post-ictal state, and family history. Provoked seizures (due to hypoglycaemia, drug toxicity, alcohol withdrawal, febrile illness) must be excluded before diagnosing epilepsy. Blood tests (glucose, electrolytes, FBC, LFTs) and ECG are useful to exclude metabolic and cardiac causes of collapse.
Living with Epilepsy
Epilepsy has significant implications for daily life. Regular evaluation of seizure control, lifestyle adjustments, and medication adherence is essential for optimal management. People with epilepsy must not drive until they have been seizure-free for at least 12 months for a Group 1 (car) licence. Group 2 (lorry/bus) licence requirements are more stringent — typically 10 years seizure-free or 3 years off treatment with specialist approval. DVLA must be notified. Employment restrictions apply to certain occupations (e.g. working at heights, in water, operating machinery). SUDEP (sudden unexpected death in epilepsy) risk should be discussed sensitively — risk is higher with frequent tonic-clonic seizures and nocturnal seizures. Patients should be advised to never stop AEDs suddenly (risk of status epilepticus), avoid alcohol excess, maintain regular sleep patterns, and wear a medical alert bracelet. The ketogenic diet may be considered in drug-resistant epilepsy, particularly in children. Vagus nerve stimulation (VNS) and epilepsy surgery are options for refractory cases.