Before you begin using a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use this medication.
Blood clotting: This medication may make it more difficult for the blood to clot. If you take anticoagulant (blood thinning) medications, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed. If you notice any signs of bleeding, such as frequent nosebleeds, unexplained bruising, or black and tarry stools, notify your doctor as soon as possible. Your doctor will order routine blood tests to make sure potential problems are caught early.
Take appropriate precautions and ensure that all doctors involved in your care are aware of all medication use. Tests for blood clotting should take place before any surgery. Platelet count and coagulant tests should take place before starting treatment with valproic acid.
Drowsiness/reduced alertness: Valproic acid may affect the mental or physical abilities needed to drive or operate machinery. Avoid driving, operating machinery, or performing other hazardous tasks until you have determined how this medication affects you.
Kidney function: Kidney disease or reduced kidney function may cause this medication to build up in the body, causing side effects. If you have reduced kidney function or kidney disease, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.
Liver function: Liver failure has occurred infrequently for people taking valproic acid, usually during the first 6 months of treatment. Children under 2 years of age who take valproic acid together with other epilepsy medications are at greatest risk (nearly 20 times greater) of developing serious liver problems. These children typically have other medical conditions such as congenital metabolic disorders, mental retardation, or organic brain disease. Liver function tests should take place before starting treatment with valproic acid.
Serious liver problems may be preceded by symptoms such as loss of seizure control, malaise, weakness, lethargy, loss of appetite, and vomiting. People who take valproic acid should tell their doctor at once if they experience these symptoms. Increases in the levels of ammonia in the blood, with or without lethargy or coma, have been reported and may be present despite normal liver function tests.
Pancreatitis: Cases of life-threatening pancreatitis (inflammation of the pancreas) have been reported for both children and adults. These can occur at any time during the use of valproic acid. If you experience signs of pancreatitis such as abdominal pain on the upper left side, back pain, loss of appetite, nausea, fever, chills, rapid heartbeat, or swollen abdomen contact your doctor immediately.
Sedation: Valproic acid may cause sedation, especially when combined with another sedating drug such as alcohol.
Suicidal thoughts: There is a small risk that this medication may result in thoughts of suicide. If you experience these symptoms or any other behaviour change while taking this medication, contact your doctor immediately. Family members or caregivers of people who are taking this medication should contact the person's doctor immediately if they notice unusual behaviour changes.
Pregnancy: There is an increased risk of birth defects for a child whose mother takes valproic acid during pregnancy. Although rare, valproic acid may cause a defect of the spine called spina bifida or slowed or reduced mental development.
Before becoming pregnant, women with epilepsy should speak to their doctor about options for seizure medications. If you become pregnant while taking this medication, contact your doctor immediately.
People who need medications to prevent major seizures should not stop taking them.
Breast-feeding: This medication passes into breast milk. If you are a breast-feeding mother and are taking valproic acid it may affect your baby. Talk to your doctor about whether you should continue breast-feeding. As a general rule, women who are taking valproic acid should not breast-feed.
Children: If valproic acid is given to children 2 years old or younger, it should be used with extreme caution and as a single medication. The benefits of seizure control should be weighed against the risk.
Seniors: People over the age of 65 may be more at risk of developing side effects from this medication and may require lower dosages.