Increase of valproate-induced hyperammonemia in normal subjects by carbohydrate intake.

Sodium valproate-induced hyperammonemia in normal subjects is increased by the intake of carbohydrates--rapidly or slowly absorbed sugars, given by mouth or IV injection. The hyperammonemia is maximal about 3 hours after carbohydrate administration. This relation between carbohydrate and ammonia metabolism has not been described previously.