Like any other medication, you can't until it has passed the amount of time it was intended to be active for. For example, Tylenol 3 is typically active for 4 - 6 hours. If you have a urine test or a blood test any sooner than that, it was a stupid decision to take it. But after the 6-hour mark, drinking coffee and water will help clear it from your urine. Just don't overdo the coffee and water. Too much coffee will make you spastic, and too much water isn't good for you if consumed in a short amount of time. If you have to get tested via blood test, however, there is nothing you can do to get it out.