Final answer:
The correct option is (b). The drug preparation is not commercially available to meet a specific medication prescription order.
Step-by-step explanation:
For non-sterile compounding to be legally performed in a pharmacy, the correct requirement is that the drug preparation is not commercially available to meet a specific medication prescription order. This practice allows pharmacists to tailor medications to the individual needs of patients when commercially produced drugs are not suitable. For example, if a patient requires a specific dosage or a different form (such as a liquid instead of a pill) that is not available in the market, a pharmacist may compound the medication accordingly.
The other options - compounding to reduce cost, fulfilling a customer request, or creating a stockpile for a doctor - are not by themselves legal justifications for nonsterile compounding. The Food and Drug Administration (FDA) regulates the safety and efficacy of pharmaceuticals in the United States, ensuring that medications produced and sold meet high standards. Compounded medications also fall under these regulations, particularly when it comes to patient safety, but are not subject to the same approval process as new or generic drugs.