1. When you pass out on a friends shag rug that is still shedding and wake up the next day covered in fuzz from the rug.
2. When you wake up and you are covered in fuzz to create the appearance you got gang banged by some teletubbies all night.
Batman: Whoa, I dont remember much after that 7th irish car bomb... I think I passed out on this rug.
Cornbread: Dude, you got pretty fuzzed up.
Batman: Word?
Cornbread: Word.
"Fizzed up" refers to the state of being successfully charmed or seduced in a refined and sophisticated manner, often with an added sense of elegance or class.
Alice: Did you see the fancy champagne Dave bought you?