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Antiepileptic / mood stabiliser

Valproic acid

Brand names: Convulex, Depakote, Episenta

Adult dose

Dose: Initial 600mg PO/day in 1-2 doses, increase by 200mg every 3 days; usual 1-2g/day (max 2.5g/day)
Route: PO/IV
Frequency: OD-BD

Clinical pearls

  • Generalised/focal epilepsy, bipolar disorder
  • MHRA: Pregnancy Prevention Programme mandatory for women under 55; men aged <55 — separate PPP introduced 2024

Contraindications

  • Pregnancy / women of childbearing potential without PPP (MHRA — black box)
  • Severe hepatic impairment
  • Mitochondrial disease (POLG)
  • Urea cycle disorders
  • Acute porphyria
  • Hypersensitivity

Side effects

  • Hepatotoxicity (severe — boxed)
  • Pancreatitis
  • Teratogenicity (high)
  • Thrombocytopenia
  • Hyperammonaemia
  • Weight gain
  • Hair loss
  • Tremor

Interactions

  • Many — strong enzyme inhibitor
  • Lamotrigine (raises levels — slow titration)
  • Carbapenems (avoid — drop levels)
  • Aspirin

Monitoring

  • LFTs
  • FBC
  • Pregnancy
  • Drug levels (selected)

Reference: BNF; NICE NG217; MHRA; https://bnf.nice.org.uk/drugs/valproic-acid/. Verify against your local formulary and the latest BNF before prescribing.

Related

Curated clinical cross-links plus same-class fallbacks.