Valproic Acid
Antiepileptic • Mood Stabilizer
Generic Name
Valproic Acid (also as Sodium Valproate, Divalproex)
Drug Class
Antiepileptic drug (AED)
Indications
- Generalized and focal seizures
- Absence seizures
- Bipolar disorder (mania)
- Migraine prophylaxis
Dosage
- Adults: Start 10–15 mg/kg/day, increase gradually (max ~60 mg/kg/day)
- Children: 10–40 mg/kg/day in divided doses
Therapeutic serum level: 50–100 µg/mL
Routes of Administration
- Oral (tablet, syrup)
- Intravenous
Mechanism of Action
Valproic acid increases brain concentrations of gamma-aminobutyric acid (GABA), inhibits voltage-gated sodium channels, and suppresses repetitive neuronal firing.
Common Adverse Effects
- Nausea, vomiting
- Weight gain
- Tremor
- Alopecia (reversible)
- Drowsiness
Serious Adverse Effects
- Hepatotoxicity (especially in young children)
- Pancreatitis
- Thrombocytopenia
- Hyperammonemic encephalopathy
Contraindications
- Active liver disease
- Urea cycle disorders
- Known hypersensitivity to valproate
Precautions
- Liver function monitoring required
- Bleeding disorders
- Children under 2 years (higher risk of hepatotoxicity)
- Do not stop abruptly
Drug Interactions
- Phenytoin, carbamazepine – altered serum levels
- Aspirin – increased valproate toxicity
- Lamotrigine – increased risk of skin rash
Pregnancy & Lactation
High teratogenic risk (neural tube defects). Avoid in pregnancy if possible. Use with caution during breastfeeding.
Patient Counseling
- Take regularly at the same time each day
- Do not stop medication suddenly
- Report abdominal pain, vomiting, or jaundice
- Regular blood tests are essential