Among the designated health services (DHS) which are the subject of the Stark law restrictions are outpatient prescription drugs.  When the Stark statute was enacted, Part D of Medicare didn't even exist; so, while it was obvious that drugs paid for under Part B, (many of which are provided in physician offices in infusions and otherwise) were covered, the answer was not so clear for drugs paid for by Part D, which may come from pharmacies, including physician owned pharmacies in some places. In fact, there is a specific regulation which sweeps Part D drugs into the ambit of Stark DHS. Physician groups which own pharmacies need to take this into account in their compensation and profit-sharing formulas.