Sodium Valproate — NZ Medication Guide
📋 Reviewed by a Registered Pharmacist NZ — This information is for general educational purposes only and does not replace professional medical advice. Always consult your doctor or pharmacist before starting, stopping, or changing any medication.
What is Sodium Valproate?
Sodium valproate is a broad-spectrum anticonvulsant and mood stabiliser used for epilepsy and bipolar disorder. This medication is funded by Pharmac for epilepsy and bipolar disorder.
What is Sodium Valproate Used For?
Used for generalised epilepsy (tonic-clonic, absence, myoclonic seizures), focal seizures, Lennox-Gastaut syndrome, and mania in bipolar disorder.
How Does Sodium Valproate Work?
Increases brain GABA levels by inhibiting its breakdown enzyme, and blocks voltage-gated sodium channels — reducing neuronal excitability. Its mood-stabilising mechanism may involve ion channel and gene regulatory effects.
How to Take Sodium Valproate
Doses range from 600–2500 mg/day in divided doses. Modified-release (Epilim Chrono®) is taken once or twice daily and may be better tolerated. Take with food. Do not crush modified-release tablets.
Common Side Effects of Sodium Valproate
- Weight gain
- Hair loss (alopecia — usually reversible)
- Tremor
- Nausea and gastric upset
- Liver enzyme elevation
- Sedation
- Peripheral oedema
Serious Side Effects — Seek Medical Attention
Contact your doctor or call 111 immediately if you experience any of the following:
- Teratogenicity (HIGHLY SIGNIFICANT — neural tube defects, autism, developmental delay — must not be used in women of childbearing potential without exceptional circumstances)
- Hepatotoxicity (including fatal liver failure — mostly young children on polytherapy)
- Pancreatitis
- Hyperammonaemia with encephalopathy
- Thrombocytopaenia
Drug Interactions
Sodium Valproate may interact with other medicines. Always inform your doctor and pharmacist of all medications you are taking. Key interactions include:
- Lamotrigine (doubles lamotrigine levels)
- Carbapenem antibiotics (meropenem — dramatically reduce valproate levels — avoid)
- Aspirin (displaces from protein binding)
- Warfarin (enhanced anticoagulant effect)
New Zealand Prescribing Information
Sodium valproate (Epilim®, Epilim Chrono® and generics) is funded by Pharmac. Medsafe has implemented a Valproate Pregnancy Prevention Programme in NZ. Women of childbearing potential must not be prescribed valproate without documented risk acknowledgement, effective contraception, and annual specialist review.
Frequently Asked Questions
Is valproate safe in pregnancy?
No — it is highly teratogenic, causing neural tube defects and developmental problems in up to 30–40% of exposed children. It must not be used in women who are or may become pregnant unless absolutely no alternative exists.
Can I drink alcohol on sodium valproate?
Alcohol should be avoided — both suppress the CNS, increasing sedation and falls risk. Alcohol also worsens seizure control and mood instability.
⚠️ Disclaimer: This page is for educational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your doctor or a qualified health provider. In New Zealand, medication availability and funding may vary — check with Pharmac or your pharmacist for current information.
Reviewed by a Registered Pharmacist NZ
References & Further Information
The following New Zealand and international resources were used to inform this page: