I don't know what triggers my monthly migraine but I have found that Citrulline malate (an extract of watermelon) a vascular dilator prevents it for me 100%. Or

I don't know what triggers my monthly migraine but I have found that Citrulline malate (an extract of watermelon) a vascular dilator prevents it for me 100%. Originally I had started taking it for sport reasons but subsequently found it fixes the migraine! Must be that my migraine is due to vascular constriction.