sodium valproate at a glance
Medicine class
Anticonvulsant or antiseizure treatment.
Main licensed uses
Epilepsy and, for selected prolonged-release products, manic episodes in bipolar disorder.
Available forms
Includes gastro-resistant and prolonged-release solid forms, oral liquids and hospital-administered intravenous solution.
Stopping treatment
Do not stop suddenly without specialist advice because seizures or mood symptoms may return.
What is sodium valproate used for?
Licensed uses depend on the formulation and reproductive-safety restrictions.
Generalised, partial and other forms of epilepsy in adults and children.
Manic episodes in bipolar disorder with selected prolonged-release products when no other effective or tolerated treatment is available.
Intravenous treatment of epilepsy in hospital when established oral treatment is temporarily not possible.
Sodium valproate is occasionally used outside selected product licences to prevent migraine.
How does sodium valproate work?
Sodium valproate dampens excessive neuronal activity. Its actions are not fully understood, but include strengthening the inhibitory effect of gamma-aminobutyric acid (GABA), which helps stabilise electrical signalling in the brain.
sodium valproate preparations and strengths
Gastro-resistant tablet
Route: Oral
Strengths: 200 mg, 500 mg
Granules
Route: Oral
Strengths: 500 mg, 1000 mg
How to take sodium valproate
Follow the instructions for the exact formulation supplied and remain consistent about taking it with or without food.
Swallow prolonged-release and gastro-resistant tablets whole; do not crush or chew them.
Episenta capsule granules may be mixed with cold or room-temperature soft food or drink if swallowing is difficult. Swallow immediately; do not chew, crush or store them.
Measure oral liquid with the supplied syringe, spoon or cup, not a kitchen teaspoon. Strandhaven oral solution should not be diluted.
Taking it with or after food may reduce stomach upset.
Do not change formulation or brand without checking with a prescriber or pharmacist.
sodium valproate side effects
Common or expected effects
- Stomach pain, nausea, vomiting or diarrhoea
- Sleepiness, tiredness or headache
- Weight gain
- Tremor
- Hair thinning or changes in hair texture
- Dry or sore mouth, or swollen gums
- Irregular or delayed periods
Get urgent medical advice
- Liver injury, including jaundice, dark urine, marked tiredness or repeated vomiting
- Pancreatitis, including severe abdominal pain, nausea or vomiting
- Unexplained bruising or bleeding
- Severe allergic reaction, angioedema, or blistering and peeling skin reactions
- Hyperammonaemic encephalopathy, including vomiting, poor coordination, confusion or reduced consciousness
- New thoughts of self-harm or suicide
sodium valproate in pregnancy
Valproate exposure during pregnancy carries a high risk of congenital malformations and lasting developmental problems. It is contraindicated for bipolar disorder during pregnancy and may be used for epilepsy only under strict specialist conditions when no effective or tolerated alternative exists. People who could become pregnant must follow the Pregnancy Prevention Programme. Anyone planning or suspecting pregnancy should contact their specialist urgently but must not stop sodium valproate without medical advice.
sodium valproate while breastfeeding
sodium valproate interactions
Check all prescribed, non-prescribed and herbal products with a pharmacist or prescriber. Important interactions include:
Carbapenem antibiotics, including meropenem and imipenem
They can rapidly and substantially reduce valproate concentrations, causing loss of seizure control; combined use should generally be avoided.
Lamotrigine
Sodium valproate slows lamotrigine clearance, increasing toxicity and serious-rash risk.
Warfarin and other coumarin anticoagulants
The anticoagulant effect may increase, raising bleeding risk.
Common questions about sodium valproate
Answers are fully visible for fast scanning and source review.
Can sodium valproate be stopped suddenly?
No. Sudden withdrawal can allow seizures or mood symptoms to return. Any change should be planned with a specialist.
What should I do if I become pregnant while taking sodium valproate?
Contact your doctor or specialist urgently. Do not stop it yourself because uncontrolled epilepsy or bipolar disorder can also be dangerous.
Does sodium valproate affect contraception?
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.