gobsmacked
astoundedly
scrabbly
disturbed
shockable
explosive
popeyed
stark raving mad
shell shock
with one's jaw in one's lap
enormously
ghastly
beyond belief
overhysterical
flabbergasting
off the rails
insano
loony
off one's head
potty
horrored
deranged
out of one's mind
barking mad
crazy as a cootie bug
astoundment
appalling
crazy as a cootie
no kidding
sweeping
disbelievably
becrazed
astoundedness
cracked as an egg
unglued
thunderstriking
poleaxe
shockingly
mad as a March hare
staggery
stupefying
peppered
unbelievably
crazy as a bedbug
spreckled
insaniac
demented
gobstruck
astonishedly
amazedly