Buy 'Certo' 32oz bottle mix it with another fluid, you'll piss alot so be ready...otherwise drink lots and lots of water...the more you drink the more it will flush out your system...the more you have in your system the longer it will take to come out...research has shown in pharmacies it takes 2-3 weeks for small doses of cannabis and 6-8 weeks for heavy doses...I would say Drink your 8 glasses of water daily fill them to the top...otherwise if they're considering taking you for a test in a few days buy Certo...you should come through with flying colours...