Management of simple and complex absence seizures; mixed seizure types; myoclonic and generalized tonic-clonic (grand mal) seizures; may be effective in partial seizures, infantile spasms, bipolar disorder; prevention of migraine headaches

Hepatic failure resulting in fatalities has occurred in patients; children <2 years of age are at considerable risk; monitor patients closely for appearance of malaise, weakness, facial edema, anorexia, jaundice, and vomiting; may cause severe thrombocytopenia, bleeding; hepatotoxicity has been reported after 3 days to 6 months of therapy;tremors may indicate overdosage; use with caution in patients receiving other anticonvulsants

Hypersensitivity to valproic acid or derivatives or any component; hepatic dysfunction

1% to 10%: Endocrine & metabolic: Change in menstrual cycle Gastrointestinal: Abdominal cramps, anorexia, diarrhea, nausea, vomiting, weight gain.
<1%: Drowsiness, ataxia, irritability, confusion, restlessness, hyperactivity, headache, malaise, alopecia, erythema multiforme, hyperammonemia, pancreatitis, thrombocytopenia, prolongation of bleeding time, transient increased liver enzymes, liver failure, tremor, nystagmus, spots before eyes

CYP2C19 enzyme substrate; CYP2C9 and 2D6 enzyme inhibitor, CYP3A3/4 enzyme inhibitor (weak) Decreased effects of phenytoin Decreased effects with carbamazepine, lamotrigine, possibly clonazepam (increased absence seizures have been reported) Increased effects/toxicity of diazepam, CNS depressants, alcohol Increased effects/toxicity with aspirin (increase valproic acid levels)

Symptoms of overdose include coma, deep sleep, motor restlessness, visual hallucinations Supportive treatment is necessary; naloxone has been used to reverse CNS depressant effects, but may block action of other anticonvulsants

When used to treat generalized seizures, patient instructions are determined by patient’s condition and ability to understand. Oral: Take as directed; do not alter dose or timing of medication. Do not increase dose or take more than recommended. Do not crush or chew capsule or enteric-coated pill. While using this medication, do not use alcohol and other prescription or OTC medications (especially pain medications, sedatives, antihistamines, or

hypnotics) without consulting prescriber. Maintain adequate hydration (2-3 L/day of fluids unless instructed to restrict fluid intake). Diabetics should monitor serum glucose closely (valproic acid will alter results of urine ketones). Report alterations in menstrual cycle; abdominal cramps, unresolved diarrhea, vomiting, or constipation; skin rash; unusual bruising or bleeding; blood in urine, stool or vomitus; malaise; weakness; facial swelling; yellowing of skin or eyes; excessive sedation; or restlessness. Pregnancy precautions: Do not get pregnant while taking this medication; use appropriate barrier contraceptive measures.