What additional criteria must a preparation meet to be classified as medium risk?

To be classified as medium risk, a preparation must require a longer-than-usual duration for compounding. This extended preparation time often involves factors like the complexity of the compounding process or the necessity of multiple steps that increase the potential for contamination, thereby necessitating stricter adherence to sterile processing guidelines.

Despite this, the classification does not solely hinge on the duration of preparation by itself; it also typically involves the number of sterile products used and the environment in which the compounding occurs. For instance, using non-sterile ingredients usually indicates a higher risk level, and compounding in environments worse than ISO class 7 would generally lead to a higher risk classification as well. Hence, while elements involving sterile products and air quality are certainly relevant considerations, the primary factor that distinguishes medium risk preparations is their unusually long preparation time.