Seizure and Epilepsy History Taking OSCE — First Seizure to DVLA Advice

Why This Station Is Tested

Seizure history taking is a high-yield OSCE station because it tests multiple competencies simultaneously: systematic history taking, safety counselling (driving, work, bathing), DVLA notification rules, and appropriate investigation planning. It also assesses your ability to obtain and use an eyewitness account — a critical component that examiners specifically look for.

First Principles: Is This a Seizure?

Before exploring the seizure itself, consider the differential. Not all episodes of collapse or loss of consciousness are seizures. The main differentials are: vasovagal syncope (most common), cardiac syncope (arrhythmia, structural heart disease — can cause brief myoclonic jerks), hypoglycaemia, TIA/stroke, psychogenic non-epileptic seizures (PNES — formerly pseudoseizures), hyperventilation/panic attack, and sleep disorders (cataplexy, parasomnias).

Opening the History

Introduce yourself and ask the patient to describe what happened in their own words. Then immediately ask: "Is there anyone with you who saw what happened? An eyewitness account is very important." Obtaining or acknowledging the value of a collateral history is an early mark-scheme point.

Systematic History Framework

Before the Episode (Pre-ictal)

• Warning/aura: any unusual sensation before the seizure? (Visual — lights, formed hallucinations; olfactory — burning smell suggests temporal lobe; gustatory; déjà vu; rising epigastric sensation — all suggest focal onset). The presence of an aura indicates focal onset.
• Precipitants: missed medication, sleep deprivation, alcohol or withdrawal, fever (especially in children), flashing lights (photosensitivity — JME), menstruation (catamenial epilepsy), metabolic disturbance (hypoglycaemia, hyponatraemia)
• Prodrome: hours/days before — irritability, headache, mood change (non-specific, seen in idiopathic generalized epilepsy)
• Posture: standing, sitting, lying — important for distinguishing from syncope (syncope typically occurs upright)

During the Episode (Ictal)

Ask the eyewitness specifically: "Did their body go stiff first? Then did they jerk? Did they bite their tongue? Did they wet themselves? How long did it last?"

After the Episode (Post-ictal)

• Confusion: how long? (Post-ictal confusion lasting >15 minutes is characteristic of seizure, not syncope — syncope has rapid recovery)
• Headache: common post-ictal
• Todd's paresis: focal weakness after focal seizure — resolves in minutes to hours (implies cortical focus)
• Memory: amnesia for the episode
• Injury: tongue, head, limbs

Prior Seizure History

First seizure or known epilepsy? If known epilepsy: usual seizure pattern, frequency, last seizure, what changed (missed medication, new trigger, intercurrent illness)?

Epilepsy-Specific History

Medication history: current antiepileptic drugs (AEDs), doses, concordance (has the patient been taking them?), recent changes, side effects. Common AEDs: sodium valproate, lamotrigine, levetiracetam, carbamazepine, phenytoin. Ask about interactions — carbamazepine induces P450 enzymes, lamotrigine levels are halved by enzyme inducers.

Past medical history: febrile convulsions in childhood, head injury, meningitis/encephalitis, family history of epilepsy, neurofibromatosis, tuberous sclerosis.

Social history: impact on daily life, driving (MUST ask about DVLA rules), employment (working at heights, operating machinery), swimming/bathing alone, childcare responsibilities.

DVLA Driving Rules — Must Know

Examiner Mark-Scheme Checklist

• ✓Asks for eyewitness account
• ✓Explores pre-ictal phase (aura, precipitants)
• ✓Asks about ictal features (stiffening, jerking, tongue bite, incontinence)
• ✓Explores post-ictal confusion/Todd's paresis
• ✓Asks about medication concordance (if known epilepsy)
• ✓Social history — driving, work, bathing
• ✓DVLA advice clearly given and documented
• ✓Appropriate investigations proposed (bloods, ECG, EEG, MRI/CT)

Frequently Asked Questions

"How do I differentiate a seizure from a vasovagal syncope in the OSCE history?"

The key distinguishing features are: prodrome (syncope typically has a pre-syncopal prodrome of nausea, sweating, greyout of vision, and light-headedness — seizures may have an aura instead), trigger (syncope triggered by prolonged standing, heat, pain or emotional stress; seizures less often have obvious triggers), posture (syncope almost always from standing/sitting; seizures can occur in any position including lying down), duration (syncope brief — seconds to 1–2 minutes; seizures typically 1–3 minutes for a tonic-clonic), recovery (syncope has rapid return of consciousness and orientation — within seconds; seizures have prolonged post-ictal confusion typically >10–15 minutes), and injuries (lateral tongue biting is highly specific for tonic-clonic seizure; tip of tongue may be bitten in syncope). Brief myoclonic jerks in syncope (convulsive syncope) can mimic a seizure — the key is that they occur after loss of consciousness, are brief and irregular, and recovery is rapid with no post-ictal phase.

"What is an aura and what does it tell you about seizure localisation?"

An aura is the subjective experience at the onset of a focal seizure before consciousness is lost — it represents the initial ictal discharge in a specific cortical region. Different aura types correlate with different seizure foci: rising epigastric sensation (a warm, nauseous feeling rising from the abdomen to the chest) is the classic aura of temporal lobe epilepsy originating from the mesial temporal structures; olfactory auras (usually unpleasant smell — burning or rotting) suggest temporal lobe or orbitofrontal cortex; visual auras (simple flashes of light = occipital lobe; formed visual hallucinations = temporal lobe); somatosensory tingling or numbness follows the somatosensory cortex homunculus (post-central gyrus); auditory auras (humming, buzzing) = superior temporal lobe; déjà vu and jamais vu = temporal lobe. In the OSCE, asking about aura and correctly interpreting the localising value of the aura type will impress examiners and demonstrates understanding beyond rote factual recall.

"What DVLA advice must I give after a first seizure and how do I document it?"

After a first unprovoked seizure, the patient must stop driving immediately and notify the DVLA. For a standard car/motorcycle licence (Group 1), they may not drive for 6 months from the date of the seizure; after 6 seizure-free months with normal investigations and specialist review, they can reapply. For a Group 2 vocational licence (HGV, PCV, or taxi), they must be seizure-free for 5 years and meet additional criteria. It is the patient's legal responsibility to notify the DVLA — failure to do so is a criminal offence. If the patient refuses to inform the DVLA and continues to drive despite your advice, you have a duty to inform the DVLA yourself, overriding confidentiality (GMC guidance), and you must document this discussion. In the OSCE, say clearly: "I need to advise you that following a seizure, you must not drive and you must inform the DVLA — this is a legal requirement." Document the advice given, that the patient understood, and their response.

"How do I take a medication history in a patient with known epilepsy?"

Start by identifying current antiepileptic drugs (AEDs): name, dose, frequency, and how long they have been taking each one. Then explore concordance directly but non-judgementally: "How have you been getting on with taking your tablets? Have you missed any doses recently?" Missed doses are the most common precipitant of breakthrough seizures. Ask about recent dose changes or new prescriptions — many drugs interact with AEDs. Carbamazepine and phenytoin are hepatic enzyme inducers, reducing the efficacy of the oral contraceptive pill, lamotrigine, and warfarin. Sodium valproate is a teratogen and absolutely requires pregnancy counselling in women of childbearing age (NICE TA 699 guidance: valproate should not be prescribed to women unless enrolled in the Pregnancy Prevention Programme). Ask about side effects: sodium valproate — weight gain, hair loss, tremor; lamotrigine — rash (Stevens-Johnson syndrome risk); carbamazepine — diplopia, ataxia, hyponatraemia; levetiracetam — mood changes, irritability.

"What investigations would you request after a first seizure?"

After a first seizure, investigations aim to: identify a reversible precipitant, exclude a structural cause, and risk-stratify for epilepsy. First-line bloods: FBC (infection, anaemia), glucose (hypoglycaemia), U&E (hyponatraemia, uraemia), calcium (hypocalcaemia), magnesium, LFTs, CRP, prolactin (elevated 10–20 minutes post-seizure — not reliable enough to confirm seizure but can support diagnosis). ECG: to exclude a cardiac cause (prolonged QT, Brugada, complete heart block). CT head (or MRI brain — preferred): to exclude structural pathology (tumour, cortical dysplasia, old infarct, AVM, cavernoma, mesial temporal sclerosis). EEG: not an emergency investigation but should be performed within a week of a first seizure — idiopathic generalised epilepsy shows characteristic generalised spike-and-wave discharge; focal epilepsies show focal spikes. Neuroimaging should be performed urgently if there is a focal neurological deficit, fever, or failure to return to normal consciousness.

"What are psychogenic non-epileptic seizures and how would they present differently?"

Psychogenic non-epileptic seizures (PNES), previously called pseudoseizures or dissociative seizures, are episodes that resemble epileptic seizures but are not caused by abnormal electrical brain activity. They are a form of functional neurological disorder and are associated with psychological distress, trauma, anxiety, or depression. Features that suggest PNES rather than epilepsy: prolonged duration (often >5 minutes; status epilepticus is rare), waxing and waning course (rather than the stereotyped sequence of epileptic seizures), pelvic thrusting and asynchronous limb movements, eyes closed during the episode (eyes are usually open during a tonic-clonic seizure), preserved awareness during apparently generalised convulsions, no post-ictal confusion or rapid return to normal, no injuries despite prolonged episodes, multiple attendances to A&E with normal investigations, and failure to respond to antiepileptic drugs. Diagnosis is confirmed by video-EEG telemetry showing no ictal activity during a typical episode. Management is psychological therapy (CBT) and treatment of underlying psychiatric conditions — NOT AEDs.

Related guides: Neurological History OSCE · Syncope and Collapse History OSCE · DVLA Fitness to Drive OSCE · Headache History OSCE · Mental State Examination OSCE