Played a competitive table tennis match a few years ago and got a migraine as we went to the bar after. I knew I couldn't drive as I could hardly see anything so I thought, why not have a cold beer while I waited for my sight to improve. I was amazed that after two quick beers the blood rush had stopped and the headache didn't follow. I am sharing this in the hope that this works for others. If I get the blurred vision I just grab a couple of bottles of beer and drink them quickly. This relaxes my body and the blood rush stops - no headache !!!