compound
confound
kick a dog when it's down
do more harm than good
kick someone when they are down
disimprove
worsen
exacerbate
exasperate
aggravate
rub salt in someone's wounds
fall away
suffer
go from bad to worse
fan the flames
impair
hit one hard
misalter
add fuel to the fire
take a turn for the worse
dismalize
twist the knife
go to shit
make matters worse
pejorate
dub
fossick
poison
drop someone in it
bring down
reap the whirlwind
tread on someone's corns
decline
run
ruin
go through hell
rub salt in the wound
come to grief
catastrophize
enervate
raise the spectre
blame
deteriorate
make heavy weather of
begin at the wrong end
pay
make one's bed and lie in it
malice
bear the brunt
visit