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Antiepileptic / mood stabiliser

Valproic acid

Brand names: Convulex, Depakote, Episenta

Valproic acid (valproate) is a broad-spectrum antiseizure medicine used across generalised and focal epilepsies and also as a mood stabiliser in bipolar disorder.

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.

Clinical monograph

How it works

Its anticonvulsant effect is attributed to increased GABAergic activity together with blockade of voltage-gated sodium and certain calcium channels, reducing neuronal hyperexcitability.

Prescribing in practice

  • Valproate is highly teratogenic, causing major congenital malformations and neurodevelopmental disorders, and must not be used in women or girls of childbearing potential unless the conditions of the Pregnancy Prevention Programme are met.
  • It can cause serious hepatotoxicity and pancreatitis, and may produce hyperammonaemic encephalopathy even with normal liver enzymes.
  • Weight gain, tremor, hair loss and thrombocytopenia are recognised effects, and many interactions arise from its enzyme-inhibiting properties.

Monitoring

Check liver function and full blood count before and during early treatment, and consider ammonia if unexplained drowsiness or confusion develops.

Counselling the patient

  • If you can become pregnant, you must use the pregnancy prevention measures and never start or continue valproate without specialist advice.
  • Seek urgent help for severe abdominal pain, unusual bruising or bleeding, or marked drowsiness and confusion.

Evidence & guidelines

MHRA safety measures, including the valproate Pregnancy Prevention Programme, govern its use in those of childbearing potential.

Reference: NICE NG217; MHRA; 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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