Valproic acid can be effective against many types of seizures common in children:

• absence seizures (this is one of the most effective medicines for these brief staring spells)
• myoclonic seizures
• tonic-clonic seizures, such as those in Lennox-Gastaut syndrome.
• infantile spasms
• seizures triggered by flashing lights

Children under 2 or 3 years of age who take valproic acid have a much higher risk of liver failure than adults or older children. (The risk is very low for children over 10, perhaps 1 in 50,000.) The risk is even higher for very young children who also take other seizure medicines, and it's highest of all for those with certain other serious disorders. Usually the doctor will not prescribe valproic acid or other valproate medicines for children at very high risk. Liver damage usually occurs within the first 6 months of treatment. The first signs of it are vomiting, loss of appetite, sluggishness, and perhaps loss of seizure control, yellow skin and eyes, or swelling.

Higher-than-usual levels of the hormone testosterone have been found in many girls who take valproic acid when they're older than about age 10. No symptoms are apparent, but the doctor may want to watch for later problems, perhaps related to weight gain.

A few children who take valproic acid seem to become more irritable but this is seldom a serious problem.

To reduce side effects, the doctor probably will prescribe a low dose of valproic acid to start and will increase it slowly. Children usually start with a dose of 5 to 10 milligrams (mg) for each kilogram (kg, about 2.2 pounds) of their body weight per day. This is usually given in one to three equal doses per day.

Most children do best at about 15 to 60 mg/kg per day. Children taking a combination of valproic acid and another seizure medicine usually need the higher doses because of interactions between the medicines.

Valproic acid syrup is an easy way to give a valproate medicine to small children who cannot swallow capsules. The medicine is absorbed by the body a bit more quickly than when Depakote sprinkle capsules are used, but the amount absorbed is the same.