There are a couple of options. You can go to the Address/Symbol editor and change the address on the symbol/description to something else. This, however, leaves the old address in the code but the description is gone. There is a replace tool found under the search menu item that will allow you to replace the addresses and/or symbols throughout the code. It is a very handy tool and it the way I would make a global change. Just select the options you want to occurr during the replace. You may need to try out the utility a couple of times to get familar with it.
Good Luck!