After drinking an equivalent amount of Champagne and regular wine - I feel significantly more light-headed after drinking the Champagne. The only difference appears to be the carbonation.
What is the property of the carbonation of champagne that makes you feel light-headed?
It's been proven here Source but the reason is still unclear.
"It must be absorbed from the digestive system quicker," says Ridout. Normally, we absorb 20 per cent of any alcohol we drink in the stomach and the remainder in the intestines. One theory is that carbon dioxide in the bubbles somehow speeds the flow of alcohol into the intestines.
