well it depends on how much she smokes and how often she smokes. Some people can pass the basic test 2-3 days after smoking. look here http://www.erowid.org/plants/cannabi..._testing.shtml if possible you best bet may be substitution http://www.urine-pimp.com I have not used this so I don't know much about it, but I have heard that people have passed with it http://boards.cannabis.com/showthrea...ght=urine-pimp I wish your friend some luck.