well man if you don't have a detox kit, I'd say go out and buy about 5 liters worth of cranberry juice, my mate did that and managed to pass a POLICE drug test, so yeah, it depends on the amount of thc in your body, like if you've been smoking heavily in the past thats if its a urine test, if its a hair test, I'd say go get you're head shaved now!, but drink as much fluids as possible and be pissing every half hour tonight.