nutsy
nerts
gaga
cray-cray
buggish
cray
crazypants
jiggy
loco
wiggy
banoodles
loced out
bammy
bananapants
off one's onion
gone fishing
off the beam
crazy-ass
off one's rocker
nutzoid
not right in the head
meshuggener
half-cracked
bananas
hatstand
bughouse
off one's chump
nutso
crackers
loony tunes
insane in the membrane
get one's freak on
becraze
gobaloon
toppy
three stops short of Dagenham
crazy as a shithouse rat
off one's head
out of one's mind
wackadoo
go ham
whacked-out
go potty
becrazed
bugnuts
demented
insano
crazy as a cootie bug
deranged
off the rails
lose one's mind
loony
potty
crazy as a cootie
nutcake
certifiable
loopy
fruit
nutball
jimjam
madhead
nut
radge
cracked as an egg
not have both oars in the water
semimadness
nut-bar
mad as a March hare
freakazoid
plumb crazy
cracky
nertz
dumb out
up the wall
craziness
mad as a cut snake
not wise
crazyish
crazen
screwy
lunatical
crazily
freeping
5150
phrenesis
tonto
nutballs
chaoticity
cooked
cuckoo
go mad
wild-ass
cuckoo for Cocoa Puffs
yabble
tapped
up the pole
nutbar