I know this was bad but at the time I was not ready to be clean and sober. I graduated from a drug program that I was ordered to go through. I became an outpatient, and they would test me at least three times per week. I would drink certo the night before and on my way to the program.. During graduation they said this women has been tested more than anyone in the history of their program, they turned to me and said we want to let her know she passed every last one of them. Certo worked for me for cocaine. I was told by some heavy weed smokers to use it, because they were testing for their po on weekly basis. I want to say, some pepole it worked for some it doesn't don't know why that is but I want to caution you to at least get a home testing kit just to double check....Hope that helps some one, I got to test in two days for a very High paying job, and I pray that I just have this chance to make it in, an I made a vow to God I will never ever ever use drugs again! I am going to let Jesus be my drug!!