Http://studenthealth.Oregonstate.Edu/answe rspot-old/alcoholdrugs/testing_stims.Htm

check out that website. It depends on how often he uses.

I hope it helps.

Crack cocaine leaves the body pretty fast, i'd say a few days or so.

I experimented with crack just a week or so ago, I am not addicted and do not want to do it again.