Possible mechanisms for migraine attacks like cerebral vasoconstriction, spreading depression, central neurotransmitter dysfunction and platelet hyperaggregation have been shown to appear in the absence of magnesium, which lead to the idea that there is a relationship between magnesium and migraine attacks. In the few years there have been many studies about the efficiency of magnesium in the treatment and prophylaxis of migraine attacks. Our study aimed to determine the efficiency of magnesium in the prophylaxis of 60 migraine patients with or without aura. After 3 months the number, duration and severity of migraine attacks were decreased in the group taking magnesium and there were no side effects causing drug discontinuance. We conclude that magnesium is effective in the prophylaxis of migraine, but further large comparative controlled studies are needed to recommend it for clinical uses.