Google has updated its local quality guidelines to officially allow the listing of multiple doctors at a single practice so long as they fit the following guidelines:
"Individual practitioners may be listed individually as long as those practitioners are public-facing within their parent organization. Common examples of such practitioners are doctors, dentists, lawyers, and real estate agents. The practitioner should be directly contactable at the verified location during stated hours. A practitioner should not have multiple listings to cover all of his or her specializations."
Google has given guidance which allowed this for a while now, however this is the first change to the guidelines to happen officially.