valproic acid
a carboxylic acid (also formulated as valproate
sodium; U.S. trade name: Depacon) used as an anticonvulsant and mood stabilizer. Although exact mechanisms of action remain unclear, valproic acid may exert its effects by reducing membrane sodium-channel activity (see ion channel), thereby slowing neuronal activity. It may also stimulate the synthesis of the inhibitory neurotransmitter gamma-aminobutyric acid (GABA). Valproic acid and valproate sodium are officially approved by the U.S. Food and Drug Administration for the management of seizures and of manic episodes associated with bipolar disorders. Although in general less toxic than lithium, these drugs have been associated with fatalities due to liver failure, particularly in children under 2 years of age, as well as pancreatitis; serum monitoring of drug levels and liver function is therefore required, particularly on starting treatment. Valproic acid and valproate sodium should not be taken during pregnancy due to
risks of neural tube defects in the fetus; fetal exposure to valproic acid in the first trimester has also been linked to an increased risk of autism. U.S. trade name: Depakene.