You did not mansion what type of drug test you will take - urine, saliva,hair. Unfortunately, marijuana is one of the safest drugs one can choose, but it's also the most easily recognizable and most difficult to get out of your system fast for a drug test. I'd say you're probably going to have to cheat if you want to pass with the little amount of time you have. You can use clean friends urine or buy a synthetic. Make sure what your friend has consumed last 48 hours. You will try to take the sample in the room with you (some use condoms or balloons), but the main thing here is to keep the urine between 91 and 97 degrees. Don't forget to have a pin in your pocket and never, never throw or flush the used stuff away. If you want you can try to get clean in a natural way - work out, keep your body hydrated, eat a high fiber diet with Metamucil ( makes the metabolites cling to the fiber and send it out), red meat and proteins (creatine). Also include in your daily diet multi vitamin and vitamin b-12.