Valproic acid can cause liver failure that may be fatal, especially in children under age 2 and in people with liver problems caused by certain genetic disorders.
You should not use valproic acid if you have liver disease, a urea cycle disorder, or a genetic disorder such as Alpers' disease or Alpers-Huttenlocher syndrome.
Do not start or stop taking  valproic acid during pregnancy without your doctor's advice. This medicine may harm an unborn baby or cause birth defects, but having a seizure during pregnancy could harm both mother and baby.
Do not use valproic acid to prevent migraine headaches if you are pregnant.
Call your doctor at once if the person taking this medicine has signs of liver or pancreas problems, such as: loss of appetite, upper stomach pain (that may spread to your back), ongoing nausea or vomiting, dark urine, swelling in the face, or jaundice (yellowing of the skin or eyes).
Do not stop using valproic acid without your doctor's advice. Stopping suddenly may cause a serious, life-threatening type of seizure.
Before taking this medicine
You should not use valproic acid if you are allergic to it, or if you have:
liver disease;
a urea cycle disorder; or
a genetic mitochondrial (MYE-toe-KON-dree-al) disorder such as Alpers' disease or Alpers-Huttenlocher syndrome, especially in a child younger than 2 years old.
Valproic acid can cause liver failure that may be fatal, especially in children under age 2 and in people with liver problems caused by a genetic mitochondrial disorder.
Tell your doctor if you have ever had:
liver problems caused by a genetic mitochondrial disorder;
depression, mental illness, or suicidal thoughts or actions;
a family history of a urea cycle disorder or infant deaths with unknown cause; or
HIV or CMV (cytomegalovirus) infection.
Some young people have thoughts about suicide when first taking valproic acid. Your doctor should check your progress at regular visits. Your family or other caregivers should also be alert to changes in your mood or symptoms.
Using valproic acid during pregnancy may increase the risk of serious birth defects that can develop early in pregnancy, even before you know you are pregnant. Using this medicine during pregnancy can also affect cognitive ability (reasoning, intelligence, problem-solving) later in your child's life. However, having a seizure during pregnancy could harm both the mother and the baby.
If you take valproic acid for seizures or manic episodes: The benefit of preventing these conditions may outweigh any risks posed by this medicine. There may be other medications that are safer to use during pregnancy. Do not start or stop taking valproic acid without your doctor's advice.
Do not use valproic acid to prevent migraine headaches if you are pregnant or you could become pregnant.
If you are not pregnant, use effective birth control to prevent pregnancy while using valproic acid. Tell your doctor if you start or stop using hormonal contraception that contains estrogen (birth control pills, injections, implants, skin patches, and vaginal rings). Estrogen can interact with valproic acid and make it less effective in preventing seizures.
It may not be safe to breastfeed while using this medicine. Ask your doctor about any risk.
