Epilepsy

One of the oldest known brain conditions: what a seizure is, the many types, causes, diagnosis with EEG, treatments from medication to surgery and diet — and what to do if you see someone having a seizure.

An ancient condition, a natural explanation

Epilepsy appears in Babylonian medical texts over 3,000 years old. The Hippocratic writers argued in On the Sacred Disease that it was a natural brain disorder, not divine punishment — yet stigma persisted for millennia, and in some places still does. The 19th-century English neurologist John Hughlings Jackson recognised that seizures arise from "occasional, sudden, excessive" discharges of grey matter, and that the features of a seizure reveal where it starts.

What is a seizure?

A seizure is a transient burst of abnormal, excessive, synchronised neural activity. Epilepsy is diagnosed when someone has an enduring tendency to have seizures — usually after two unprovoked seizures, or one with a high risk of more. About 50 million people worldwide have epilepsy (WHO).

Types

Focal seizures start in one area of one hemisphere. Depending on where, they may cause twitching of one hand, a strange smell, déjà vu, a rising feeling in the stomach, or staring and automatic movements such as lip-smacking with impaired awareness. They can spread to become bilateral. Generalised seizures involve both hemispheres from the start: tonic-clonic seizures (stiffening then rhythmic jerking, loss of consciousness), absence seizures (brief staring spells, common in children, often mistaken for daydreaming), and myoclonic jerks.

Causes and diagnosis

Causes include genetic factors, brain injury, stroke, infections, tumours and developmental malformations; in many cases no cause is found. Diagnosis relies on a careful description of events (video from a phone is valuable), EEG to detect abnormal electrical patterns, and MRI to look for structural causes.

Treatment

The WHO estimates up to 70% of people with epilepsy could become seizure-free with appropriate treatment, usually anti-seizure medications. For drug-resistant focal epilepsy, surgery to remove the seizure focus can be highly effective. Other options include vagus nerve stimulation, responsive neurostimulation, deep brain stimulation, and the ketogenic diet, especially in children. A purified CBD medicine is approved for certain severe childhood epilepsies.

First aid for a tonic-clonic seizure

Stay calm and time it. Move hard objects away and cushion the head. Do not put anything in the person's mouth or restrain them. When the jerking stops, roll them onto their side (recovery position) and stay until they're fully aware. Call emergency services if the seizure lasts more than 5 minutes, another follows, they're injured, pregnant, or it's their first seizure.