There are different kinds of migraines, and they are caused by different things. I get what my doctor said are called "Classic Migraines." I lose part of my vision, sometimes I see sparkles, once I got sick to my stomach. Then about 20 minutes after I lose part of my vision I get the headache. The doctor said the blood vessels to the eyes close up, then after about 20 minutes they open, causing the headache. He prescribed some pills, which I had to take after the headache started.
Then I started reading about it and found out that Niacin keeps the blood vessels open (also helping with cholesterol), so I tried it. I used to get a migraine every week or two. Now I get one every year or two, if that. I buy the non-flushing Niacin capsules at WalMart. They only cost a few dollars and have done wonders for me.
Barbara