(See also FIT; SEIZURE.) Epilepsy is the name given to any condition in which a person suffers repeated fits or seizures. It is present in one in 200 of the population and up to 5 per cent of all children will have had a fit by the age of 12, although most of these are harmless accompaniments of an acute feverish illness.
It is a recurrent and paroxysmal disorder, starting suddenly and ceasing spontaneously, due to occasional sudden, excessive, rapid and local discharge of the nerve cells in the grey matter (cortex) of the BRAIN. Epilepsy always arises in this way from the brain, but its origin is often of microscopic size. It is diagnosed by the clinical symptoms based on the observations of witnesses. Its cause can sometimes be established by laboratory tests, and brain scanning. Fits can be the first sign of a tumour, or follow a stroke, brain injury or infection, but in the large majority no underlying cause is found – so-called idiopathic epilepsy.
A single epileptic fit is not epilepsy. Of those people who have a single seizure, a significant minority (20 per cent) have no further attacks.
have a sudden, often unprovoked onset; the patient emits a cry, then falls to the ground, rigid, blue, and then twitching or jerking both sides of the body: the tonic-clonic convulsion. Drowsiness and confusion may last for some hours after recovering consciousness. Some experience a momentary warning (AURA): a smell, a sensation in the head or abdomen, or a visual disturbance.
begin with twitching of the angle of the mouth, the thumb, or the big toe. If the seizure discharge then spreads, the twitching or jerking spreads gradually through the limbs. Consciousness is preserved unless the seizure spreads to produce a secondary generalised fit. In some attacks the eyes and head may turn, the arm may rise, and the body may turn, while some patients feel tingling in the limbs.
The patient usually appears blank, vacant and may be unable to talk, or may mumble or chatter – though later they often have no memory of this period. They may be able to carry out complex tasks, taking off gloves or clothes, and may smack their lips or rub repeatedly on one limb (automatisms). A sense of strangeness supervenes: unreality, or a feeling of having experienced it all before (hence the term déjà vu). There may be a sense of panic. Strange unpleasant smells and tastes are olfactory and gustatory hallucinations, and visual hallucinations evoke complex scenes. An initial rising sense of warmth or discomfort in the stomach, or ‘speeding-up’ of thoughts are common psychomotor symptoms. All these strange symptoms are brief, disappearing within a few seconds to a few minutes.
Attacks start in childhood and last a few seconds. The child ceases what he or she is doing, stares, looks a little pale, and may flutter their eyelids. The head may drop forwards. Attacks are commonly provoked by overbreathing. The child and parents may be unaware of the attacks – ‘just daydreaming’. Major fits develop in one-third of subjects. By contrast with other types of epilepsy, the ELECTROENCEPHALOGRAM (EEG) is diagnostic.
Children with epilepsy should take part in normal school exercises and games, and can swim under supervision. Adults must avoid working at heights, with exposed dangerous machinery and driving vehicles on public roads. Current legislation in the UK allows a licence to drive after two years of complete freedom from attacks during waking hours; those who for more than three years have had a history of attacks only while asleep may also drive.
identifies, and avoids where possible, any factors (such as shortage of sleep or excessive alcohol) which aggravate or trigger attacks. If fits are very infrequent, treatment may not be recommended. However, frequent fits may be embarrassing, may cause injury or, in the worst cases, cause long-term brain damage, so treatment is often recommended. Anti-epileptic drugs are usually prescribed for several years under medical supervision. The choice of drug I based on the type of epilepsy and the balance of risk and benefit, with the dose governed by the degree of control; sometimes drug levels can be monitored by blood tests to further refine dosage. The table summarises some of the commoner anticonvulsant drugs in use. Interactions can occur between anti-epileptics and, if drug treatment is changed, the patient needs careful monitoring. In particular, abrupt withdrawal of a drug should be avoided as this may precipitate severe rebound seizures.
Indications | |
|---|---|
M = major generalised tonic-clonic; P = partial or focal; CP = complex partial (temporal lobe); PM = petit mal; JME = juvenile myoclonic epilepsy. | |
First-choice drugs: | |
Ethosuximide | PM, JME |
Phenobarbitone | M, P |
Phenytoin | M, P, CP |
Carbamazepine | M, P, CP |
Valproate | M, PM, JME |
Second-line drugs: | |
Primidone | M, P, CP |
Clobazam | M, CP |
Vigabatrin | M, CP, P |
Lamotrigine | M, CP, P |
Gabapentin | M, CP, P |
Topiramate | P |
As all anticonvulsant drugs have an effect on the brain, it is not surprising that there may be side-effects, especially involving alertness or behaviour. In each case careful assessment is necessary for doctor and patient to agree on the best compromise between stopping fits and avoiding ill-effects of medication.
Patients who have an epileptic seizure should not be restrained or have a gag or anything else placed in their mouths; nor should they be moved unless in danger of further injury. Any tight clothing around the neck should be loosened and, when the seizure has passed, the person should be placed in the recovery position to facilitate a return to consciousness (see APPENDIX 1: BASIC FIRST AID).