Epilepsy and Seizures: Types, Triggers, and Antiepileptic Medications

When someone has a seizure, it’s not just a single event-it’s often a sign of something deeper. Epilepsy isn’t a one-size-fits-all condition. It’s a group of brain disorders where the brain’s electrical system goes haywire, leading to repeated seizures. The epilepsy diagnosis isn’t made just because someone had a seizure. You need at least two unprovoked seizures more than 24 hours apart, or one seizure with a high chance of more. That’s the standard set by the International League Against Epilepsy (ILAE), the global authority that updates how we understand and classify this condition. Their latest system, released in early 2025, changed how doctors talk about seizures-and it matters because getting the type right directly affects what medication you get.

How Seizures Are Classified Now (2025 Update)

Older terms like "partial" or "complex partial" are gone. The 2025 classification cuts down from 63 named seizure types to just 21. Why? Because too many labels confused doctors and patients alike. The new system focuses on what’s most useful: where the seizure starts and what it looks like.

First, every seizure gets grouped into one of four main types:

• Focal seizures - start in one area of one brain hemisphere. About 60% of all epilepsy cases are this type.
• Generalized seizures - involve both sides of the brain from the start. Seen in about 30% of cases.
• Unknown onset - you don’t know where it began, usually because there’s no witness or EEG wasn’t done.
• Unclassified - not enough information to say anything.

For focal seizures, the big split is whether awareness changes:

• Aware - you’re fully conscious. You might feel a strange smell, see flashing lights, or have a rising sensation in your stomach. These make up about 25% of focal seizures.
• Impaired awareness - you zone out, stare blankly, or do automatic things like fumbling with clothes or mumbling. This is the most common focal seizure type, making up 75% of cases.

Generalized seizures come in six forms:

• Absence - brief staring spells, often mistaken for daydreaming. Common in kids.
• Myoclonic - sudden muscle jerks, like a shock.
• Tonic - muscles stiffen up, often causing falls.
• Clonic - rhythmic jerking, usually in arms and face.
• Tonic-clonic - the classic "grand mal" seizure: stiffening, then shaking, often with loss of consciousness.
• Atonic - muscles suddenly go limp, leading to drops or falls.

What’s new? The term "awareness" is replaced with "consciousness," which now means both knowing what’s happening AND being able to respond. Also, instead of saying "motor" or "non-motor," doctors now say "observable" (things you can see) or "non-observable" (things only the person feels). This helps catch seizures that don’t look like much but still disrupt the brain.

What Triggers Seizures?

Not all seizures happen for the same reason. Triggers vary wildly between people. Some common ones include:

• Sleep deprivation - being up all night is one of the top triggers across all epilepsy types.
• Flashing lights - only affects about 3% of people with epilepsy, but it’s real. Known as photosensitive epilepsy.
• Stress - emotional or physical stress can lower the seizure threshold.
• Missed medication - even one skipped dose can set off a seizure in some.
• Hormonal changes - many women with epilepsy notice more seizures around their period. This is called catamenial epilepsy.
• Alcohol or drug use - not just heavy drinking. Even a few drinks can interfere with seizure meds.
• Low blood sugar - common in people with diabetes or those who skip meals.

Here’s the catch: triggers aren’t the same as causes. A trigger sets off a seizure in someone who already has epilepsy. The cause could be genetic, a past brain injury, a tumor, or an infection like meningitis. In about 60% of cases, doctors never find the exact cause. That doesn’t mean it’s not real-it just means we don’t know yet.

Antiepileptic Medications: How They Work and What’s Used

There are over 30 different antiepileptic drugs (AEDs) approved in the U.S. and Europe. But you don’t just pick one at random. The choice depends on the seizure type, the epilepsy type, and the person’s age, gender, and other health issues.

For focal seizures, first-line drugs include:

• Lacosamide - works by stabilizing overactive nerve cells.
• Levetiracetam - modulates brain chemicals involved in seizure spread.
• Carbamazepine - blocks sodium channels, a classic choice for decades.
• Valproate - broad-spectrum, but not used in women of childbearing age due to birth defect risks.

For generalized seizures, especially absence or myoclonic types:

• Ethosuximide - first choice for absence seizures in kids.
• Valproate - effective for multiple types, but has serious side effects.
• Lamotrigine - good for generalized tonic-clonic and absence seizures.
• Clonazepam - sometimes used short-term for myoclonic seizures.

For combined generalized and focal epilepsy (a newer category making up 5-8% of cases), doctors often start with broad-spectrum drugs like:

• Valproate
• Lamotrigine
• Levetiracetam

Medication isn’t just about picking the right one. It’s about finding the right dose. Too little and seizures continue. Too much and you get dizziness, fatigue, or memory issues. About 30% of people don’t respond fully to the first drug they try. That’s why doctors often try one at a time, waiting weeks to see if it works.

Side effects vary. Some drugs cause weight gain (valproate), others weight loss (topiramate). Some affect mood (levetiracetam can cause irritability). Some increase the risk of birth defects (valproate, phenytoin). Women planning pregnancy need special counseling-some drugs are safer than others.

Why Misclassification Hurts

A 2023 study found that 27% of people got the wrong medication because their seizure type was misclassified. That’s not rare. It happens often.

For example, if someone has a subtle focal seizure that looks like daydreaming, a doctor might mistake it for absence epilepsy. So they prescribe ethosuximide-which works for absence seizures but does nothing for focal ones. The person keeps having seizures. The doctor thinks the dose is too low. They increase it. Side effects get worse. The real problem? The wrong drug.

Another common mix-up: confusing psychogenic non-epileptic seizures (PNES) with epileptic ones. PNES look like seizures but come from psychological stress, not abnormal brain electricity. About 20-30% of people sent to epilepsy centers have PNES. They don’t need antiepileptic drugs. They need therapy. But without a proper EEG or video monitoring, they’re often misdiagnosed and put on meds that don’t help-and cause harm.

And here’s the real cost: people with misclassified epilepsy are 34% less likely to stick with their treatment. They lose trust. They stop taking pills. Their seizures get worse. A 2023 study in Epilepsy & Behavior showed that accurate classification led to better adherence-and fewer hospital visits.

What’s Changing in Diagnosis and Treatment

Tools are getting smarter. The ILAE is rolling out an AI-assisted diagnostic tool in late 2025. It analyzes EEG patterns and seizure descriptions to suggest the most likely type. Early tests show it boosts accuracy by 18% for doctors who aren’t epilepsy specialists.

Genetic testing is also becoming part of diagnosis. Some epilepsy syndromes are tied to specific gene mutations. If a child has infantile spasms and a mutation in the SCN1A gene, that’s Dravet syndrome. The treatment is different than for other seizure types. Knowing the gene can change everything.

But access isn’t equal. In low-income countries, 75% of people with epilepsy never get diagnosed properly. No EEG. No neurologist. No accurate classification. They get whatever medication is available-and often, it’s not the right one.

Meanwhile, in the U.S., the CDC reports that only 58% of rural patients get an EEG within 72 hours, the recommended window. Delays mean misdiagnoses pile up.

What Patients Need to Know

If you or someone you care about has seizures, here’s what matters:

• Write down everything: when the seizure happened, what it looked like, how long it lasted, what happened before and after. Eyewitness accounts are gold.
• Ask: "Is this focal or generalized?" Don’t let vague terms like "partial" confuse you.
• Request an EEG within 72 hours if possible. Even a normal EEG doesn’t rule out epilepsy.
• Know your meds. Ask what they’re for, what side effects to watch for, and what to do if you miss a dose.
• Track triggers. Keep a simple log: sleep, stress, alcohol, menstrual cycle.
• If you’re not improving after 3 months on one drug, ask about switching. Don’t wait.

There’s no cure for epilepsy yet. But with the right classification and medication, 70% of people can live seizure-free. That’s not a dream-it’s the standard. The problem isn’t the disease. It’s getting the diagnosis right.