Most doctors start patients on 5 to 12.5 mg/kg (250-750 mg) of valproic acid per day. The dosage is then usually increased each week by 5 to 10 mg/kg until seizures stop or the patient experiences too many side effects. Most patients take a total of 750 to 3,000 mg each day, divided into two or three doses. Taking more than 4,000 mg per day is seldom recommended.

Children may require higher doses and seniors usually need less.A therapeutic blood level of valproate is generally considered to be 50-100 mcg/mL (lower for seniors), but adjustments should depend on clinical response.

• Algorithm for dosing valproate
• Algorithm for adding lamotrigine to valproate
• Algorithm for adding valproate to lamotrigine