Sleepy...Like Aranger said, there are specific tests for each pain med. Hydrocodone (Vicodin) & oxycodone (oxycontin) are 2 different chemicals. They will show up as two different drugs. In PM, if you are given a drug screen, you can be fairly certain it will be for specific drugs to make sure you are compliant. If you are not, you are out of Pain Mangament, usually with no questions asked. At least, that's how it is with my doc. If I'm taking something he didn't prescribe, sorry, I'm SOL.
Did you sign a medication contract? Most people in PM do, some don't, although rare. If you did, you signed a contract stating you would only take meds prescribed by your doc alone, and nothing else, and in the manner in which it was prescribed (i.e., not taking more than prescribed). Taking more than presecribed, which will show up as well in specific tests (the quantity) is grounds for termination, as well. You really have to follow their rules to a T. We all do. If we don't, we know where we will end up. Trust me, if you are fired, there are numerous people waiting to take your place that will follow the rules. If you are fired, I can be fairly certain it will be very difficult for you to find another doc willing to treat you with opioids because you have shown noncomplicance. Take care.