I am a senior nursing student. We just had a stimulation lab where we had to give morphine iv push (2mg/1ml). Our med book says that you don't have to dilute but because you are suppose to push this medication over 5 minutes, it is a lot easier to dilute it in 10 ml of NS and push 2 mls every minute for 5 minutes. We flush with normal saline before and after given this med. When you flush afterwards, make sure you also flush slowly or it defeats the purpose of pushing in the med slowly. I am not sure about what is done differently if IV fluid is running. I am pretty sure that we have to stop the IVF or put it on pause while we give the push. I don't think you would want to use the IVF to flush afterwards because it may flush to quick? I will have to double check with my teacher.