Don't waste your $ on shampoo for cleansing your hair for hair folicle testing...it doesn't work!! I know...i did it and it still came back positive!! And
the product i bought supposedly had a guarantee!! It guaranteed (in small print)to clean your hair of all "impurities" which technically, it did! Nothing can change the outcome of the test...nothing will penetrate the hair shaft! The best you can do is wait 90 days after last use to test!