Safety and efficacy of intravenous sodium valproate in the treatment of acute migraine.

This multicenter study investigated the safety and efficacy of intravenous valproate in acute migraine attacks and the possible impact of prophylactic valproate pre-treatment. Thirty-six patients established on migraine prophylaxis were administered 500 mg sodium valproate intravenously against acute migraine attacks. Pain development was assessed by visual analogue scale up to a 24 hours follow up interview to detect e.g. possible relapse symptoms. A subgroup analysis examined whether prophylactic treatment with valproate affected its acute anti-migraine efficacy. A meaningful headache reduction within two hours was achieved in all 12 patients with and in 20 out of 24 patients without valproate prophylaxis. Headache-associated signs and symptoms were substantially reduced. No serious side-effects were reported. The results confirm the therapeutic value of intravenous valproate in acute migraine attacks described in literature and show a beneficial effect on all investigated efficacy parameters with a trend to even better response in patients receiving valproate prophylaxis.