A Double-Blind, Randomized, Multicenter, Parallel Dose Study to Evaluate the Safety and Efficacy of Zonisamide 150 mg and 300 mg Per Day and Placebo in Subjects With Migraine Headache

The pharmacologic treatment of migraine may be acute (abortive, symptomatic) or preventive (prophylactic). Preventive medication is usually given daily for months or years; however, treatment may also be given in an intermittent regimen. Most migraine prophylactic medications were designed to treat other disorders, and they can be divided into three groups:

1. Serotonergic or monoaminergic agents such as methysergide, which have demonstrated high degrees of effectiveness;
2. Non-serotonergic drugs such as beta-blockers, tricyclic antidepressants, valproate; and
3. Drugs with lesser demonstrated effectiveness, such as selective serotonin reuptake inhibitors, calcium channel antagonists, and non-steroidal anti-inflammatory drugs.

The choice of treatment must be individualized, and is influenced by contraindications, potential side effects, the need to treat associated symptoms like tension-type headache and insomnia, and drug cost.

Anticonvulsants, such as valproate, have shown significant degrees of efficacy in migraine prophylaxis when used in low doses. Considering the differences in proposed mechanisms of action of these agents, it is likely that a novel anticonvulsant such as zonisamide may also be an effective prophylactic treatment for migraine.