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Antiepileptic

Sodium Valproate (Epilepsy in Elderly)

Brand names: Epilim Chrono, Episenta

Used in: Seizures & Epilepsy

Sodium valproate is an antiepileptic for generalised and focal epilepsy and a mood stabiliser; its use is tightly restricted in girls and women of childbearing potential because of serious risks in pregnancy.

Dosing — being independently re-sourced

ClinCalc Pro is rebuilding its dose data from primary open sources — the manufacturer SmPC (eMC), the WHO Model Formulary and other official references — under clinician review. This drug's structured dose is not yet published here. Confirm all doses against the product SmPC and your local formulary before prescribing.

US labelling (FDA)

Reference — US labelling, may differ from UK

Valproic acid oral solution is intended for oral administration. ( 2.1 ) Simple and Complex Absence Seizures: Start at 10 to 15 mg/kg/day, increasing at 1 week intervals by 5 to 10 mg/kg/week until seizure control or limiting side effects ( 2.1 ) Safety of doses above 60 mg/kg/day is not established ( 2.1 , 2.2 ) 2.1 Epilepsy Valproic acid oral solution is intended for oral administration. Patients should be informed to take valproic acid oral solution every day as prescribed. If a dose is missed it should be taken as soon as possible, unless it is almost time for the next dose. If a dose is skipped, the patient should not double the next dose. Valproic acid is indicated as monotherapy and …

Source: US FDA prescribing information (openFDA / DailyMed), label dated 2024-05-27. Accessed 2026-06-12. US dosing and indications can differ from UK practice — use UK sources for prescribing decisions.

Clinical monograph

How it works

It increases GABA activity and affects sodium channels to raise the seizure threshold; the mechanism is multifactorial.

Prescribing in practice

  • It is highly teratogenic and causes neurodevelopmental harm — it must NOT be used in girls or women able to have children unless the conditions of the Pregnancy Prevention Programme are met (MHRA), and is increasingly avoided in this group altogether.
  • Hepatotoxicity (rare but serious, especially in young children), pancreatitis, thrombocytopenia and weight gain occur.
  • It inhibits the metabolism of some drugs — for example it raises lamotrigine levels, so the lamotrigine dose must be lowered.

Monitoring

Check liver function and full blood count (especially early); review pregnancy-prevention requirements at least annually in anyone of childbearing potential.

Counselling the patient

  • If you can become pregnant, you must use highly effective contraception and follow the Pregnancy Prevention Programme — seek urgent advice if you plan or suspect pregnancy.
  • Report abdominal pain, vomiting, easy bruising, or yellowing of the skin or eyes.
  • Do not stop it suddenly.

Evidence & guidelines

Effective in generalised epilepsy but subject to strict MHRA pregnancy-prevention restrictions; avoided in those who could become pregnant wherever possible.

Reference: NICE CG137; BPS Epilepsy in the Elderly guidelines; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. Monograph status: clinician-reviewed (2026-07-04).

Related

Curated clinical cross-links plus same-class fallbacks.

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