I am not a doctor.... so, I hope you hear me
in that the script the doc has
in mind for you may be your only way to solve the issue (or at least try) but again, I would look at alllllll options. You may be told that you could use either type (bio or synthetic) and that there is no difference between the two, but I would strongly beg to differ.
I have no idea what the doctor will say, but I would encourage you to do some research on this so you can ask about options.