I choose Morphine because it is the stronger of the two and it lasted longer, but it wasn't enough and they designed a"cocktail"specifically for me. BUT...if it is not enough be sure to tell them and they will be able to make what is known as a"designer"cocktail that will help with your pain. You need to be as comfortable as possible so that you can heal and get up and moving as soon as possible....not rushing out of the hospital, just up and moving. DO NOT be afraid to ask for more pain medication if you do not feel it is enough. You are having MAJOR, MAJOR surgery!!!!Peace&Love