What is Epilepsy — and What Are Its Symptoms?

Epilepsy is a neurological condition in which a person’s brain is prone to producing recurrent, unprovoked seizures. A seizure happens when a sudden burst of abnormal electrical activity disrupts normal brain function — and because different brain areas control different tasks, seizures can look very different from person to person. Globally, epilepsy affects tens of millions of people and is considered a common chronic brain disorder. 

Seizures are the main symptom — but they vary widely

The single defining symptom of epilepsy is seizures, yet “a seizure” is not one single experience. Clinicians divide seizures into broad categories (focal, generalized, and unknown onset) based on where in the brain the abnormal activity starts and whether awareness is affected. Some seizures cause dramatic whole-body shaking and loss of consciousness; others are very brief and subtle — a momentary blank stare, a sudden twitch, or an unusual smell or feeling (an “aura”) that the person senses before other symptoms begin. Understanding the type of seizure helps guide diagnosis and treatment. 

Common symptoms you may see or feel

Because seizures reflect which part of the brain is involved, symptoms fall along a spectrum. Typical signs include:

• Convulsive symptoms: sudden stiffening of the body followed by rhythmic jerking of the arms and legs (tonic-clonic seizure).
   
• Brief staring spells or “absence” seizures: sudden stops in activity and blanking out for a few seconds, often mistaken for daydreaming.
   
• Focal (partial) seizures with preserved awareness: unusual sensations such as tingling, a rising feeling in the stomach, sudden intense fear, or a repetitive movement like lip-smacking.
   
• Focal seizures with impaired awareness: the person may appear confused, perform automatic movements, and be unresponsive to others for a minute or two.
   
• Autonomic symptoms: changes in heart rate, sweating, flushing, or nausea during a seizure.
   
• Post-ictal phase: after a seizure a person may feel tired, confused, have a headache, or have temporary weakness in a limb — recovery varies with the seizure type.
   

Because the presentation is so variable, careful eyewitness descriptions (what happened, how long it lasted, triggers) are often crucial to diagnosis. 

Causes — many, sometimes none found

Epilepsy can arise for many reasons. In some people the cause is obvious — a serious brain injury, stroke, brain infection (for example, encephalitis), certain developmental brain abnormalities, or genetic syndromes. In others, no clear cause is identified despite testing; we call these idiopathic or genetic-generalized forms depending on clinical patterns and testing. Some triggers (like fever in young children, alcohol withdrawal, or specific medications) can provoke a seizure without implying chronic epilepsy. Knowing possible causes helps guide management and prevention. 

How epilepsy is diagnosed

Diagnosing epilepsy starts with history and observation. Because seizures may be brief or occur when no one is watching, doctors rely on careful descriptions from witnesses, any available video (even a phone video can be extremely helpful), and a medical history that includes possible triggers or injuries.

Key tests that help confirm a diagnosis and find the seizure type include:

• Electroencephalogram (EEG): records electrical activity in the brain and may show patterns suggestive of epilepsy, though a normal EEG does not rule it out.
   
• Neuroimaging (MRI, sometimes CT): used to look for structural causes such as scarring, tumors, vascular malformations, or developmental abnormalities.
   
• Blood tests and other evaluations: to rule out metabolic causes, infections, or medication effects.
   
• Specialist assessment: if first-line testing is inconclusive, prolonged video-EEG monitoring or genetic testing may be recommended.
   

Together, history + EEG + imaging let neurologists determine whether a person has epilepsy, what seizure type they have, and the most appropriate treatment plan. 

When to seek help — and what to tell the doctor

See a doctor if you or someone you care for has had:

• Two or more unprovoked seizures, or
   
• A single seizure with a high chance of recurrence (for example, after a brain injury), or
   
• A seizure that lasts more than 5 minutes, or
   
• A seizure followed by breathing difficulty, severe confusion, or head injury.
   

Bring any eyewitness accounts, videos, a list of medications, recent illnesses, and a timeline of events — these details speed diagnosis and safety planning. 

Living with epilepsy — treatment and safety

Epilepsy is often treatable. Most people achieve good seizure control with antiseizure medications, and others may benefit from diet therapies, neurostimulation (for example, vagus nerve stimulation), or surgery when medications fail. Education, lifestyle adjustments (sleep, alcohol, medication adherence), and an individualized safety plan are essential parts of care. With modern treatments and support, many people with epilepsy lead full, active lives.

If you’d like, I can adapt this post into:

• a printable patient handout that explains seizure first-aid and safety tips,
   
• an FAQ you can place on your clinic website, or
   
• a short script for a clinic video (30–60 seconds) explaining when to seek urgent care.
   

— Dr. Chirag Gupta