Epilepsy Diagnosis
How Epilepsy Is Diagnosed: From First Seizure to Treatment Plan
The thing nobody warned me about was how slow the diagnosis would feel. I had a seizure, then another, then a long series of appointments and waiting rooms — and somewhere in the middle of all that, the word "epilepsy" was finally said out loud. By that point I'd been carrying the question around for months.
If you or someone you love has had a first suspected seizure, the journey from that moment to a clear treatment plan can be confusing. There are tests with letters that mean nothing if you've never met them. There are gaps in the timeline that feel longer than they should. And there's a real risk of being told something at the start that gets revised later.
This is what I learned about the diagnostic journey from going through it myself, talking to others in the epilepsy community, and reading widely afterwards. It's not medical advice — I'm not a clinician — it's a personal account, with the research that helped me make sense of things along the way. It's the article I would have wanted to read while I was sitting in those early waiting rooms.
How Often Each Test Helps
Diagnosis is rarely a single moment. It's a chain of investigations, each with its own strengths and blind spots.
Approximate Diagnostic Yield by Test
Source: UK national guideline NG217 (2022); Smith et al., QJM (1999).[1][3] Figures are approximate ranges from published literature.
The Six Stages of Diagnosis
From the day of the first seizure to a finalised plan — what each step looks like, and why each one matters.
For me, the gap between A&E and the first specialist appointment felt like the longest few weeks of the year. What I didn't know at the time — and what I think would have helped — is that the official UK guidance is for a referral to a specialist epilepsy service to happen within two weeks of a suspected seizure.[1] In practice that referral comes through a GP, A&E or whichever clinician saw the person first, and the specialist is usually a neurologist with an interest in epilepsy or, in some areas, an epilepsy nurse specialist who works alongside one.
Looking back, the single most useful thing I brought to that first appointment wasn't a scan or a test result — it was the story. From everything I've learned since, most epilepsy diagnoses are made on history rather than tests. The clinician wanted to know what I remembered before, during and after the event, and crucially what someone else had witnessed. If a partner, parent or paramedic saw what happened, their account turned out to be more useful than anything I could remember on my own. The thing I wish I'd done is write it all down in the days afterwards while it was fresh.
- Your written timeline of the event — what you and others noticed
- Any phone video that may have been captured
- A list of medications, recent illnesses, alcohol intake, sleep that week
- Family medical history if you know it
- A second person who can speak to what they saw
Two tests did most of the work in my own diagnosis, and I wish I'd understood what each one was actually looking for before I had them.
An EEG (electroencephalogram) records the electrical activity of the brain through small electrodes placed on the scalp. From what I learned, it's looking for patterns that suggest a tendency toward seizures. The thing nobody told me at the time is that a normal EEG doesn't rule out epilepsy — published figures suggest a standard recording picks up the relevant patterns in only around a quarter to half of people with the condition.[1] A sleep-deprived EEG, where you stay up late before the test, raises the sensitivity considerably, which is why it's often the second step.
An MRI scan looks at the structure of the brain rather than its electrical activity. It's hunting for any visible cause — a developmental difference, scarring, an old injury, or a tumour. In focal epilepsy, the literature suggests MRI finds a structural cause in around 30% of cases.[1] Mine came back clear, and I remember worrying that meant something was being missed. What I came to understand is that a clear MRI isn't a failure of the scan — for most people with epilepsy, the cause simply isn't structural.
For more difficult cases, a video EEG in hospital records both brain activity and behaviour over hours or days. From what I've read, it's considered the gold standard for distinguishing seizure types and ruling out events that look like seizures but aren't.
In my own case, the first appointment didn't give me a tidy answer. From what I've heard from others in the epilepsy community, that's far more common than I realised — sometimes the EEG and MRI are both normal even when seizures are clearly happening, sometimes the seizure type is hard to pin down without seeing one captured live, and a working diagnosis can get revised once more information comes in.
Something I wish more people talked about is misdiagnosis. Published research suggests around 20–30% of adults initially diagnosed with epilepsy have a different condition causing their events.[3] The most common imitators I read about are vasovagal syncope (faints), psychogenic non-epileptic seizures (now sometimes called dissociative seizures), and certain types of migraine. The reverse also happens — people with genuine epilepsy are sometimes told it's stress or anxiety for months before the diagnosis lands. Either way, the treatments for these conditions are not interchangeable, which is why it matters.
If something about your diagnosis doesn't sit right — events that don't respond to medication, a story that doesn't quite match the label — you have every right to ask for a second opinion or a referral to a tertiary epilepsy centre.[5] Getting this part right matters enormously, because the treatments for these conditions are not interchangeable.
"Diagnosis is rarely a single moment. It's a story that gets clearer with each piece of information."
— NuroEaseThis distinction took me a while to fully grasp, and I think getting it muddled is partly why those early months felt so confusing. The way I now understand it: a seizure is an event, while epilepsy is a tendency for that event to recur. The NHS notes that around 1 in 10 people will have a single seizure at some point in their life, and that on its own doesn't mean they have epilepsy.[6] A seizure can be triggered by a fever, a head injury, low blood sugar, alcohol withdrawal, severe sleep deprivation, or certain medications. These are called provoked seizures, and from what I've learned, they don't usually require ongoing treatment.
Epilepsy itself is formally defined by the International League Against Epilepsy as either two unprovoked seizures more than 24 hours apart, or one unprovoked seizure with a high probability of recurrence (typically over 60% based on imaging or EEG findings), or the diagnosis of a recognised epilepsy syndrome.[7] I share this not as someone qualified to diagnose anyone — that's always a clinician's job — but because knowing the distinction shaped how I understood my own situation, including the implications for driving and daily life.
The DVLA has specific rules. Any seizure means you must stop driving and notify the DVLA. Re-licensing depends on the type of seizure, whether it was provoked, and how long you've been seizure-free. Don't guess — check the current rules at gov.uk/epilepsy-and-driving.[8]
Once my diagnosis was made, the conversation moved to treatment. From what I've experienced and read since, that usually means anti-seizure medication for most people, chosen by a specialist based on seizure type, age, sex, other medications and lifestyle. The stated goal is simple but harder to achieve: the lowest effective dose of a single medication that controls seizures with manageable side effects.
The thing I wish someone had told me earlier is that the first medication isn't always the right one. Published research suggests roughly half of people achieve seizure freedom on their first prescription, and the rest need adjustments, switches or combinations.[9] Knowing that earlier would have saved me a lot of self-blame in the first year — it's a normal part of the process, not a sign that anything's wrong with you.
First-line treatment for most people. Choice depends on seizure type — for example, lamotrigine and levetiracetam are commonly used for focal seizures, sodium valproate or levetiracetam for generalised types.[1]
Not a replacement for medication, but a meaningful adjunct. Consistent sleep, stress management and a stable daily rhythm reduce seizure burden for many people.
For drug-resistant epilepsy, options include a second medication, ketogenic diet, vagus nerve stimulation, or evaluation for epilepsy surgery at a tertiary centre.[1]
A simple log of seizures, sleep and triggers makes every appointment more useful. The patterns it reveals are often more informative than any single test.
Every appointment goes faster than you think it will. Writing your questions down before you go in is the single most useful habit I picked up.
- What type of seizure am I having, and what type of epilepsy do you think this is?
- Why this medication, and what are the realistic side effects?
- What should I do if I have another seizure on this medication?
- How long until we know whether this is working?
- Are there lifestyle factors I should focus on alongside the medication?
- What should I tell the DVLA, and when can I drive again?
- Who do I contact if something changes between appointments?
- A seizure lasts longer than 5 minutes
- One seizure follows another without recovery in between
- Breathing does not return to normal afterwards
- The person is injured during the seizure
- It is the person's first ever seizure
NuroEase Support
A calm starting point for the early days
If you're somewhere in the diagnostic journey — newly referred, recently diagnosed, or still trying to make sense of it — our free epilepsy guide is a plain-English place to begin. It walks through the basics of tracking, triggers and what to take to your next appointment, with no pressure and no jargon.
References & Sources
- NICE — Epilepsies in children, young people and adults (NG217). nice.org.uk (2022)
- Hauser W. et al. — Risk of recurrent seizures after two unprovoked seizures. New England Journal of Medicine, nejm.org (1998)
- Smith D. et al. — The misdiagnosis of epilepsy and the management of refractory epilepsy in a specialist clinic. QJM, academic.oup.com (1999)
- Epilepsy Society — Non-epileptic seizures (dissociative seizures). epilepsysociety.org.uk (2024)
- Epilepsy Action — Getting a second opinion. epilepsy.org.uk (2024)
- NHS — Epilepsy overview. nhs.uk (2023)
- Fisher R. et al. (ILAE) — A practical clinical definition of epilepsy. Epilepsia, onlinelibrary.wiley.com (2014)
- DVLA — Epilepsy and driving: your legal responsibilities. gov.uk (2024)
- Kwan P. & Brodie M. — Early identification of refractory epilepsy. New England Journal of Medicine, nejm.org (2000)