Indications
Valproic Acid is used to treat many types of epilepsy (seizures), including absence seizures, generalised seizures and focal seizures, either alone or with other medicines. It is also used for the manic phase of bipolar disorder and, in some cases, to prevent migraine in adults.
How It Works
Valproic Acid increases the level of GABA, the brain’s main calming chemical messenger, and blocks certain sodium and calcium channels in nerve cells. Together these effects reduce the abnormal electrical bursts in the brain that cause seizures and help steady mood.
Dosage and Administration
Take exactly as prescribed. The dose depends on the condition and body weight; the doctor usually starts low and increases slowly, using blood tests and response to guide the dose. Swallow capsules whole with water, preferably with or after food to reduce stomach upset; do not chew. Take at the same times every day. Do not stop suddenly, as this can bring on seizures; the doctor will reduce the dose gradually if needed.
Interactions
Valproic Acid interacts with many medicines. It raises levels of Lamotrigine, Phenobarbital, Ethosuximide and Zidovudine. Carbamazepine, Phenytoin and Phenobarbital can lower its levels. Carbapenem antibiotics (such as Meropenem and Imipenem) sharply lower its levels and should be avoided. Aspirin can increase its effects and bleeding risk; Warfarin effect may increase. Topiramate may raise ammonia levels. Alcohol increases drowsiness.
Contraindications
- Active or severe liver disease, or a family history of severe liver disease linked to Valproate.
- Known mitochondrial disorders such as POLG-related disease.
- Urea cycle disorders.
- Porphyria.
- Pregnancy for bipolar disorder or migraine; in epilepsy only if no other suitable option exists.
- Allergy to Valproate.
Side Effects
Common side effects include nausea, stomach upset, tremor, weight gain, increased appetite, hair thinning or loss, drowsiness and changes in menstrual periods. Low platelet counts can cause easy bruising.
Get urgent medical help for signs of liver injury (unusual tiredness, loss of appetite, vomiting, yellowing of the skin or eyes, swelling of the legs or abdomen), severe stomach pain spreading to the back (possible pancreatitis), confusion or drowsiness that is getting worse, unusual bleeding or bruising, a severe skin rash, or thoughts of self-harm.
Pregnancy and Lactation
Valproic Acid can cause serious birth defects and problems with learning and development in children exposed in the womb. Girls and women who can become pregnant must not use it unless other treatments are unsuitable and a pregnancy prevention programme with effective contraception is followed. Do not stop it on your own if you become pregnant; contact your doctor urgently. Small amounts pass into breast milk; breastfeeding should be discussed with the doctor.
Precautions and Warnings
Liver function and blood counts are checked before and during treatment, especially in the first 6 months. Children under 3 years and people taking several anti-seizure medicines are at higher risk of liver damage. It can cause drowsiness, so take care when driving. Tell your doctor before any surgery, as it may affect blood clotting.
Overdose
Overdose can cause deep sleepiness, confusion, slow breathing, low blood pressure and coma. Seek emergency medical help immediately and take the pack with you.
Therapeutic Class
Antiepileptic (anticonvulsant); mood stabiliser.
Storage
Store below 30°C in a dry place, away from light and out of the reach of children.
Prepared by the Oshud Alo team from standard drug references. For information only; always follow your doctor's advice.