Does it show up on a drug test if you overdose OD?

I am not sure if I'm 100% understanding your question here. It sounds like you are wondering if you were to overdose on an opiate such as hydro or oxycodone would it show up in a drug test at say perhaps the hospital or other wonderful institution where your OD has brought you. And the answer is absolutely yes. If you are having an OD and you are able to communicate you should immediately tell whoever is treating you or someone who can relay the message exactly what you are on so that they can, I don't know, at the very least save your life. If you are having an OD I would think you are past the point of hiding what you did and priority number one should be getting the proper medical treatment IMMEDIATELY. And that becomes difficult if you are trying to be dishonest with what is going on.