I'm not sure about refasting but I can set your mind at ease about the dizzyness effecting your driving- at least from my experience. When I did my 30 day fast it was with only one glass of water a day and plenty of aches and pains that you probably don't get so much with the water flushing you out. I felt dizzy pretty much from day one but continued to ride my motorbike to work etc each day with no problems. I think the dizzyness is just a natural symptom of our body changing and whatever system interprets that change constantly adjusting to it, but because the body is changing steadily with the fast, the dizzyness should rarely get out of hand. And I think that fainting while sitting in a car is very unlikely, it's just one of those unreasonable fears people have about the fasting. In my opinion. :)