Use of intravenous valproic acid for acute migraine

OBJECTIVE: To review the literature regarding the use of intravenous valproic acid in aborting an acute migraine attack. DATA SOURCES: A MEDLINE (1967-June 2007) and bibliographic search of the English-language literature was conducted using the search terms valproic acid and migraine disorders. STUDY SELECTION AND DATA EXTRACTION: All articles indentified through the search were included. DATA SYNTHESIS: Divalproex sodium is approved by the Food and Drug Administration for the prevention of migraine headaches. The use of intravenous valproic acid has been studied as a possible treatment for acute migraine. Available studies are small, mostly open-label and non-placebo-controlled, and used variable doses. Valproic acid has not been shown to be superior to comparator drugs and was inferior to prochlorperazine in one trial. CONCLUSIONS: Intravenous valproic acid has not been proven effective for acute migraine treatment. Future trials should be larger, placebo-controlled, and use a standardized dose and outcome measures.