Non-Sterile to Sterile Compounding Flashcards

A technician must prepare a sterile solution from a non-sterile bulk powder known to be heat-labile. Which method of sterilization is most appropriate for the final preparation?

Answer: Sterilization by filtration using a 0.22-micron filter

Heat-labile substances are damaged by high temperatures, making dry heat and steam sterilization (autoclaving) unsuitable. Sterilization by filtration removes microorganisms by passing the solution through a 0.22-micron filter without using heat, thus preserving the integrity of the drug.

When compounding a parenteral product from a non-sterile bulk drug powder, why is performing a Bacterial Endotoxin Test (BET) a critical quality control step?

Answer: It detects fever-causing pyrogens from bacterial cell walls.

Non-sterile starting components carry a risk of contamination with endotoxins, which are fever-causing substances (pyrogens) released from the cell walls of gram-negative bacteria. A Bacterial Endotoxin Test (BET) is required by USP for these preparations to ensure patient safety, as endotoxins can be present even if the final product is sterile (free of living microbes).

A pharmacy compounds a batch of sterile ophthalmic drops from non-sterile ingredients and sterilizes the final solution by filtration. The batch does not undergo sterility testing. According to USP Chapter guidelines for Category 2 CSPs, what is the maximum beyond-use date (BUD) if the batch is stored in a refrigerator?

Answer: 7 days

According to USP , when a Category 2 Compounded Sterile Preparation (CSP) is made from non-sterile components and is not terminally sterilized or subjected to sterility testing, the BUDs are significantly restricted. For refrigerated storage (2°C to 8°C), the maximum BUD is 7 days.

A technician is preparing for a non-sterile to sterile compounding session and needs to ensure the glass vials used will be free of both microbial life and pyrogens. Which piece of equipment is required to achieve this?

Answer: Depyrogenating oven

A depyrogenating oven uses high-temperature dry heat (typically 250°C or higher) to destroy both microorganisms and pyrogens (endotoxins). An autoclave uses steam to sterilize but is not effective at destroying endotoxins. Therefore, for rendering glassware pyrogen-free, a depyrogenating oven is essential.

Which of the following quality control measures is required by USP to assign a beyond-use date (BUD) of up to 180 days to a batch of CSPs made from non-sterile ingredients?

Answer: Passing a sterility test performed on the batch

To assign an extended beyond-use date, such as those for Category 3 CSPs (up to 180 days), USP requires rigorous quality control. A critical requirement for the release of that specific batch is passing a sterility test according to USP to confirm the absence of viable microorganisms. While BET is also required, the sterility test is what validates the sterilization process to allow for a long BUD.

A hospital pharmacy is preparing a large batch of a heat-stable electrolyte solution from bulk, non-sterile powders. The plan is to terminally sterilize the CSPs after they have been packaged into their final sealed glass vials. What is the most common and effective method for this process?

Answer: Steam sterilization (autoclaving)

Terminal sterilization is the process of sterilizing a product in its final, sealed container. For aqueous (water-based), heat-stable solutions, steam sterilization (autoclaving) is the preferred and most common method. It provides a high level of sterility assurance. Filtration is a sterilization method but occurs before packaging and is not considered terminal sterilization.