This is one of those I definitely know what I am talking about, but I really don't know for sure what I am talking about.
There are certain databases, which AC uses. They haven't always. And, with access, you could edit 'till your heart's content. In fact, Brian made one and I made another complete database that people actually exchanged for the AC one. I still keep it. Took two months to make it.
But, the ICD-9 codes and CPT codes are licensed and you can't change them. Well, not without going into the SQL database and even then...
The meds are a complete database, which I doubt AC had anything to do with. Surescripts likely has the complete ownership. Not sure if it is actually their database. It would be nice to take out meds we don't use, just like it would be nice to have "Fall" come up as "Fall" instead of Fell from a train and killed an employee. The ICD-9 codes are worse than the medications. At least AC remembers the medications.