What is the requirement regarding the 5% rule for pharmacy distribution of controlled substances?

The correct requirement regarding the 5% rule for pharmacy distribution of controlled substances is based on total dosage units dispensed. This rule dictates that a pharmacy may distribute up to 5% of the total controlled substances it dispenses in a calendar year without needing to register as a distributor. The focus on total dosage units ensures that the regulation is applied uniformly, taking into account the actual quantity of controlled substances handled rather than other factors such as revenue or inventory levels. This is important for maintaining compliance with regulations while allowing pharmacies a certain level of operational flexibility in their distribution practices.