So I was sort of sketchy about this because I literally have the worst luck ever with drug tests (even when im clean)! But PLEASE do not pass this up if you're doubtful, so was I... but I used it like the instructions said and my hair test was clean! Dont waste your time and money on all the other so called cleansing shampoos, they wont work! Buuyy it, you won't regret it.