A 16-year-old girl presents to the neurology clinic with a 2-year history of early-morning bilateral arm jerks causing her to drop objects, followed occasionally by generalized tonic-clonic seizures. Her EEG shows the pattern marked **A** in the diagram — generalized polyspike-and-wave discharges activated by photic stimulation. Which of the following is the most appropriate first-line antiseizure drug for this patient?

Question

Accepted Answer

D. Levetiracetam. ## Why Levetiracetam is right

The photoparoxysmal generalized polyspike-and-wave pattern marked **A** is the hallmark EEG finding of Juvenile Myoclonic Epilepsy (JME), the commonest idiopathic generalized epilepsy of adolescence. The clinical triad of early-morning myoclonic jerks, generalized tonic-clonic seizures, and typical absences, combined with the characteristic EEG response to photic stimulation, confirms JME. In a woman of childbearing potential, valproate is contraindicated due to teratogenicity (neural tube defects, polycystic ovaries, lower IQ in exposed offspring). Levetiracetam is therefore first-line, along with lamotrigine. It is effective across all three seizure types in JME and lacks the reproductive toxicity of valproate.

## Why each distractor is wrong

- **Valproate**: Although the most efficacious drug for JME overall (controlling all three seizure types in >80%), it is teratogenic and contraindicated in women of childbearing potential due to MHRA/FDA restrictions. A 16-year-old girl must avoid this drug.
- **Carbamazepine**: Sodium-channel blockers, including carbamazepine, can worsen myoclonus and absences in JME and are contraindicated. This is a critical safety issue in this syndrome.
- **Phenytoin**: Like carbamazepine, phenytoin is a sodium-channel blocker that can paradoxically worsen myoclonic and absence seizures in JME and must be avoided.

**High-Yield:** Photoparoxysmal polyspike-and-wave on EEG = JME; in women of childbearing age, use levetiracetam or lamotrigine (not valproate); avoid sodium-channel blockers (carbamazepine, phenytoin, oxcarbazepine).

[cite: Harrison's 21e Ch 425; ILAE Classification 2017]

Answer

A. Carbamazepine

Answer

B. Valproate

Answer

C. Phenytoin

Explanation

Why Levetiracetam is right

Why each distractor is wrong

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