I made this mistake once and it was awful ! A friend of mine made the same mistake this week and again it was awful ! If you have a patient with an epidural post for pain do not give Nubain. It works like Narcan and patient goes into pain/agony. Our anesthesists always order it for break-thru pain but hey it doesn't work, just the opposite. I will never make that mistake again ! I understand it doesn't work like Narcan on everyone but on a large percentage and why take the chance. Has anyone else had this same experience?