Synopsis
Choose antiseizure treatment from the electroclinical syndrome and the person’s wider risks, titrate one medicine transparently, monitor meaningful outcomes and toxicity, and recognise when specialist or tertiary review is preferable to serial empirical prescribing.
- Confirm that recurrent events are epileptic, classify each seizure using the 2025 ILAE classes, and formulate epilepsy type separately as focal, generalized, combined generalized and focal, or unknown before selecting a medicine; the wrong narrow-spectrum agent can aggravate absence or myoclonus.
- NICE first-line monotherapy for focal seizures is lamotrigine or levetiracetam, with the other considered if the first is unsuccessful; comorbidity and reproductive safety often decide between them.
- For generalised tonic-clonic seizures, NICE offers lamotrigine, levetiracetam or sodium valproate, but valproate is subject to stringent MHRA restrictions and lamotrigine can occasionally worsen myoclonus.
- Ethosuximide is first line for isolated absence seizures; myoclonic seizures generally need a broad-spectrum choice and avoidance of carbamazepine, phenytoin, gabapentin and related aggravating agents.
- Start low, titrate at the product- and interaction-specific rate, define the target seizure type and allow an adequate tolerated trial before declaring failure unless toxicity requires earlier change.
- Routine antiseizure serum concentrations are not a substitute for clinical review; use levels selectively for pregnancy, suspected non-adherence, toxicity, interactions, organ dysfunction or unexplained loss of control.
- From 2024, valproate should not be started in a new patient under 55 unless two specialists independently document that no other effective or tolerated option exists, or compelling reasons make reproductive risks inapplicable.
- After failure of two appropriately chosen and tolerated regimens, consider drug-resistant epilepsy and refer for tertiary evaluation rather than assuming additional medicine combinations are the only option.
Key red flags
New or worsening myoclonus, absence or generalised convulsions after a sodium-channel medicine should prompt urgent review of the electroclinical classification and possible medicine-induced aggravation.
Painful or extensive rash, blistering, mucosal erosion, facial oedema, fever or organ symptoms after lamotrigine, carbamazepine or another culprit requires emergency assessment rather than watchful titration.
Irritability, aggression, depression or suicidal thinking can emerge with several agents and is particularly important to ask about after levetiracetam initiation or dose increase.
Investigation priorities
Define what improvement or failure will mean before medication changes alter the clinical picture.
Management branches
Epilepsy is confirmed or treatment after a first seizure is justified by the recurrence-risk assessment.
- 1. Define seizure type and possible syndrome, revisiting witness, EEG and MRI evidence when focal and generalised features conflict.
- 2. Compare recommended options against pregnancy potential, contraception, mood, cognition, weight, organ function, interactions, occupation and the person’s treatment priorities.
- 3. Explain intended benefit, common and serious adverse effects, missed-dose and sick-day actions, driving implications and how quickly benefit can reasonably be judged.
- 4. Prescribe one medicine with a written titration and review plan, using current BNF, MHRA and local formulary instructions rather than memory alone.