Migraine is one of the most common neurologic disorders.It usually shows up with pulsating headache, aura, nausea, vomit, photophobia, or phonophobia. Migraine pathophysiology is not yet quite clear. Recent studies show a reduction in glutamate level of cerebrospinal fluid in chronic migraineurs, specially,in those with headache resulted from drug overdose. Memantine is an effective drug on the glutamate N-methyl-D-aspartate (NMDA) system that works as a receptor antagonist.In the current study, migraineurs according to IHS diagnostic criteria(18-65 year-old males and females) who had experienced migraine attacks over 2 times a month and had never used prophylactic medications were included. All possible side-effects of the drug were explained to the patients and their consent was obtained. Afterwards, they received10mg/d Memantine or placebo in two randomized groups, and were followed up for 3 months. The primary result was change from baseline at three months in monthly attack frequency. The secondary results indicate the average number of the days with migraine headaches in a month, the average pain severity from 0 to 3 before using painkillers, the kind and dose of the drugs used in each attack, the number of respondents (50% or more reduction in attacks frequency, 50% or more reduction in the number of days experiencing migraine), side-effects (onset, end), severity(mild, average, severe), and risk.MIDAS, SF-12, and HADS will be filled to investigate patients’ progress both in the beginning and at the end of the study. If the headache is not treated or is worsening, the patient will be treated by the standard migraine prophylactic medications, and eventually the problem will be detected.