Valproic acid sodium salt is a HDAC inhibitor by selectively inducing proteasomal degradation of HDAC2, used in the treatment of epilepsy, bipolar disorder and prevention of migraine headaches.

Valproic acid is an analog of the natural fatty acid valeric acid. The sodium salt of valproic acid has long been used as an anticonvulsant to prevent many kinds of seizures. It is an inhibitor of histone deacetylases (HDACs), inhibiting Class I HDACs with an IC50 of ~2 mM.Valproic acid also inhibits glycogen synthase kinase 3 (GSK3) and depletes cellular inositol-1,4,5-trisphosphate (1,4,5-IP3).Because of these actions, valproic acid shows promise in combination therapy for cancer and in treating Alzheimer’s disease.Valproic acid (1 mM) also has pronounced effects on stem cell differentiation and self-renewal.