Sodium Valproate (Epilim)

Sodium valproate is used to treat epilepsy. The IV route is chosen only when the oral/nasogastric route is unavailable. The therapeutic range for trough plasma valproic acid levels is 40–100 mg/l (278–694 μmol/l), though there is a less reliable correlation between the level and efficacy. The oral form is available as a liquid (200 mg/5 ml), which is useful for nasogastric administration, and tablets, crushable tablets and in modified release formulations. Sodium valproate should not be confused with valproic acid (as semi-sodium valproate), which is licensed for acute mania.

Uses
All forms of epilepsy, including emergency management

Administration
For conversion of oral to IV doses, the same daily dose is used in divided doses administered over 3–5 min

Initiating IV valproate: 400–800 mg (up to 10 mg/kg), then IV infusion of up to 2.5 g maximum

To prepare, reconstitute 400-mg vial with 4 ml diluent provided and further dilute to a convenient volume with sodium chloride 0.9% or
glucose 5%. It may be administered as a bolus over 3–5 min or as a continuous infusion

Oral: usually 20–30 mg/kg/day in two divided doses

Adverse effects
Transient raised LFTs
Severe liver dysfunction, which can be fatal
Hyperammonaemia and hyponatraemia
Rarely exanthematous rash

Cautions
Pancreatitis
Liver toxicity
Sodium valproate is eliminated mainly through the kidneys, partly in the form of ketone bodies; this may give false positives in urine testing Sodium valproate concentrations are reduced by carbamazepine and phenytoin.Valproate increases or sometimes decreases phenytoin levels, and increases levels of lamotrigine

Organ failure
Renal: no dose adjustment required
Hepatic: avoid if possible; hepatotoxicity and hepatic failure may occasionally occur