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Antiepileptic Pregnancy: See neurology entry. CONTRAINDICATED unless absolutely necessary.

Sodium Valproate (Epilepsy in Elderly)

Brand names: Epilim Chrono, Episenta

Adult dose

Dose: Elderly: start 200 mg twice daily; titrate to 500–1500 mg/day
Route: Oral (modified-release preferred in elderly)
Frequency: Twice daily (standard); once daily (modified-release)
Max: 2500 mg/day
In elderly, use modified-release formulation for smoother levels. Start low (200 mg BD or 500 mg MR OD). Titrate slowly. MHRA VPPP applies regardless of age for women of childbearing potential. Elderly: encephalopathy risk higher — monitor closely. Avoid abrupt withdrawal.

Paediatric dose

Route: Oral
Frequency: Varies
Max: See neurology entry
See neurology/psychiatry entries for full paediatric dosing.

Dose adjustments

Renal

No specific dose adjustment; monitor clinically.

Hepatic

Contraindicated in hepatic impairment.

Clinical pearls

  • In elderly: hyperammonaemic encephalopathy can present as acute confusion — check ammonia and valproate level
  • Modified-release (Chrono) preferred in elderly for compliance and tolerability
  • Avoid in cognitive impairment — sedation, tremor, and hyperammonaemia are poorly tolerated
  • Consider levetiracetam as alternative in elderly — fewer interactions, no monitoring needed

Contraindications

  • Hepatic impairment
  • Pregnancy (women of childbearing potential without VPPP)
  • Mitochondrial disorders

Side effects

  • Hyperammonaemic encephalopathy (important in elderly — presents as acute confusion, lethargy)
  • Tremor, sedation
  • Weight gain
  • Hair loss
  • Hepatotoxicity
  • Hyponatraemia (SIADH less common than with carbamazepine)

Interactions

  • Carbapenems — reduce valproate levels significantly (see neurology entry)
  • Lamotrigine, meropenem, warfarin — see neurology entry

Monitoring

  • Serum valproate level
  • Ammonia (if encephalopathy suspected)
  • LFTs
  • FBC

Reference: BNFc; BNF; NICE CG137; BPS Epilepsy in the Elderly guidelines. Verify against your local formulary and the latest BNF before prescribing.

Related

Curated clinical cross-links plus same-class fallbacks.

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