NAPLEX QBANK Sterile and Non-Sterile Compounding Questions and Answers — Questions and Answers
Question 1: A pharmacist needs to compound an ointment containing 100 mg of a potent corticosteroid powder using 19.9 g of a petrolatum base. To ensure the active ingredient is uniformly distributed, which of the following compounding techniques is most appropriate?
- Spatulation on an ointment slab without any specific order
- Tumbling in a motorized mixer for 10 minutes
- Geometric dilution (Correct answer)
- Levigation with a volatile solvent
Correct answer: Geometric dilution
Geometric dilution is the process of thoroughly mixing a small amount of a potent drug with a large amount of a diluent. The process involves mixing the smaller quantity of powder (the corticosteroid) with an approximately equal quantity of the diluent (petrolatum base). This mixture is then combined with an equal portion of the diluent, and the process is repeated until all the diluent is incorporated. This ensures the final product is homogeneous.
Question 2: According to USP Chapter <797>, which of the following represents the correct sequence for donning personal protective equipment (PPE) before entering the buffer area for sterile compounding?
- Don gown, wash hands, don sterile gloves, don shoe covers.
- Wash hands, don shoe covers, don gown, don sterile gloves in buffer area.
- Don shoe covers and hair cover, wash hands, don gown, apply alcohol-based hand scrub, don sterile gloves. (Correct answer)
- Don sterile gloves, don gown, wash hands, don hair cover.
Correct answer: Don shoe covers and hair cover, wash hands, don gown, apply alcohol-based hand scrub, don sterile gloves.
USP <797> outlines a specific garbing procedure to minimize contamination, moving from dirtiest to cleanest activities. Personnel should first don shoe covers, head/facial hair covers, and face masks. Following this, they must perform hand hygiene. After hand washing, a non-shedding gown is donned. An alcohol-based surgical hand scrub should be used before entering the buffer area. Sterile gloves are the last item to be donned, typically inside the buffer room just before compounding.
Question 3: A batch of parenteral nutrition (PN) solutions is prepared in an ISO 5 primary engineering control located within an ISO 7 buffer room. The compounding involves multiple additions and manipulations. According to the revised USP <797> guidelines, what is the maximum beyond-use date (BUD) for this Compounded Sterile Product (CSP) if it is stored in a refrigerator?
- 48 hours
- 30 hours
- 14 days
- 9 days (Correct answer)
Correct answer: 9 days
The revised USP <797> categorizes CSPs based on the environment in which they are compounded rather than by low, medium, or high risk. A CSP prepared in an ISO 5 PEC within an ISO 7 buffer room is considered a Category 2 CSP. For aseptically processed Category 2 CSPs without sterility testing, the maximum BUD when stored under refrigeration (2°C to 8°C) is 9 days, assuming stability data supports it.
Question 4: A pharmacist is preparing a powdered formulation and needs to reduce the particle size of a coarse, crystalline substance to create a fine, uniform powder. Which non-sterile compounding technique best describes this process?
- Levigation
- Trituration (Correct answer)
- Spatulation
- Eutectic mixing
Correct answer: Trituration
Trituration is the process of rubbing, grinding, or pulverizing a powder to reduce its particle size. This is typically done in a mortar with a pestle. Levigation involves reducing particle size by triturating it in a mortar or on an ointment slab with a small amount of a liquid in which the solid is not soluble. Spatulation is the blending of powders with a spatula, and eutectic mixing refers to the liquefaction of two solids when mixed together.
Question 5: Which of the following correctly describes the air pressure relationship required by USP <797> for a non-hazardous sterile compounding cleanroom suite?
- The buffer area and anteroom must be at a negative pressure relative to the general pharmacy area.
- The buffer area must be at a positive pressure to the anteroom, and the anteroom must be at a positive pressure to the general pharmacy area. (Correct answer)
- The anteroom must be at a higher positive pressure than the buffer area to create an air lock.
- All compounding areas, including the buffer and anteroom, should have equal air pressure to the surrounding pharmacy.
Correct answer: The buffer area must be at a positive pressure to the anteroom, and the anteroom must be at a positive pressure to the general pharmacy area.
To prevent the influx of lower-quality air, USP <797> requires a positive pressure cascade for non-hazardous compounding. The buffer area (the cleanest room, typically ISO 7) must maintain a positive pressure relative to the adjacent anteroom (typically ISO 8). The anteroom, in turn, must maintain a positive pressure relative to the unclassified general pharmacy area. This ensures that air flows from cleaner spaces to less clean spaces, reducing the risk of contamination.
Question 6: A technician needs to accurately measure 8 mL of glycerin, a viscous liquid, for a non-sterile compound. Which piece of equipment would provide the most accurate measurement?
- A 10 mL beaker
- A 25 mL graduated cylinder
- A 10 mL oral syringe (Correct answer)
- A 50 mL conical graduate
Correct answer: A 10 mL oral syringe
For measuring viscous liquids like glycerin, a syringe is more accurate than a graduated cylinder. Because glycerin is thick, a significant amount can cling to the inner surface of a graduated cylinder, leading to an inaccurate volume being delivered. An oral syringe allows for the complete and forceful expulsion of the liquid, ensuring a more accurate volume is transferred. Beakers and conical graduates are less accurate for measuring small volumes.
NAPLEX QBANK Sterile and Non-Sterile Compounding Questions and Answers
A pharmacist needs to compound an ointment containing 100 mg of a potent corticosteroid powder using 19.9 g of a petrolatum base.
To ensure the active ingredient is uniformly distributed, which of the following compounding techniques is most appropriate?