insane
balmy
bananas
barmy
bats
batty
beany
bonkers
buggy
bughouse
bugs
cracked
crackers
crazy
cuckoo
daffy
daft
demented
dippy
dotty
flaky
flipped
freaked-out
fruitcakey
fruity
gaga
goofy
haywire
just plain nuts
kooky
loony
loopy
mad
nutty
off the hinges
off the track
off the wall
potty
round the bend
screwball
screwballs
screwy
slaphappy
unbalanced
wacky
Klutz
Lutz
abuts
buts
butts
cuts
gluts
guts
huts
juts
klutz
lutz
mutts
putts
putz
ruts
schmutz
shuts
struts