So I heard about this bark called palo azul that you boil into water like tea. I went out and bought 6 packs for $12 and boiled 1 pack into a half gallon of water. After I finished it, I tested myself 2 hours later and I passed. I'm on probation so I had been smoking heavily for 19 days straight and then I stopped for 4 days and drank the brew and passed. This shit is great!!