Valproic acid

Valproic acid

Neurological Prescription only ATC code: N03AG01

What it is

Valproic acid is an anticonvulsant that raises brain GABA activity and damps repetitive neuronal firing through effects on sodium channels. It is prescription-only and is used for epilepsy and for the prevention of migraine attacks. It is taken to prevent episodes, not to relieve one that has already started.

Typical dose
300–1500 mg
2× a day
Times
With food

Used for

  • Epilepsy
  • Migraine

What to know while taking it

It is taken with food, which softens the stomach upset it often causes. Liver enzymes, platelets and albumin are watched because the drug can injure the liver, lower platelet counts and displace other drugs from protein binding; it also depletes folate, zinc and selenium over time. Combining it with lamotrigine slows that drug's clearance and raises the risk of a serious rash, and with acetylsalicylic acid it can push free valproate levels and bleeding tendency up. Appetite and weight commonly increase, sometimes substantially, and stopping suddenly can trigger seizures.

When to see a doctor

Yellowing of the eyes or skin, dark urine, persistent vomiting, unusual bruising or bleeding, or sudden drowsiness and confusion call for a doctor without delay. Pregnancy, or planning one, must be discussed with a doctor before anything is changed, since this drug is not used in pregnancy.

Worth knowing

  • Not during pregnancy
  • Watch liver enzymes
  • Can change body weight
  • Do not stop abruptly

Markers to watch

Nutrients affected

  • vitaminB9 — depleted by (Folate, Hemoglobin, Homocysteine)
  • zinc — depleted by (Free T3, Testosterone, TSH)
  • selenium — depleted by (Free T3, Free T4, TSH)

Reference information, not medical advice. Discuss any change with your doctor.