DHA Pharmacist Sterile & Non-Sterile Preparations 1 — Questions and Answers
Question 1: Which ISO cleanroom classification is required for the preparation of sterile injectable medications?
- ISO 5 (Class 100) for the critical zone within a laminar airflow workbench (Correct answer)
- ISO 8 (Class 100,000)
- ISO 7 (Class 10,000) only
- ISO 9 (unclassified room)
Correct answer: ISO 5 (Class 100) for the critical zone within a laminar airflow workbench
Sterile product compounding requires the critical working zone to be ISO 5 (Class 100), ensuring ≤100 particles ≥0.5 µm per cubic foot to prevent microbial and particulate contamination.
Question 2: What is the purpose of a biological safety cabinet (BSC) Class II in pharmacy aseptic compounding?
- To protect both the operator and the product from hazardous drug contamination using vertical unidirectional airflow (Correct answer)
- To maintain positive air pressure only
- To sterilise the final product by heat
- To store ready-made IV preparations
Correct answer: To protect both the operator and the product from hazardous drug contamination using vertical unidirectional airflow
A Class II BSC uses vertical laminar airflow and HEPA filtration to simultaneously protect the pharmacist from exposure to cytotoxic/hazardous drugs and maintain product sterility.
Question 3: Which sterilisation method is preferred for heat-stable aqueous injectable preparations?
- Moist heat sterilisation (autoclaving at 121°C, 15 psi, 15–20 minutes) (Correct answer)
- Dry heat sterilisation at 160°C
- Ethylene oxide gas sterilisation
- UV radiation sterilisation
Correct answer: Moist heat sterilisation (autoclaving at 121°C, 15 psi, 15–20 minutes)
Autoclaving uses saturated steam under pressure (121°C, 15 psi) to achieve the most reliable and validated sterilisation for heat-stable aqueous pharmaceutical preparations.
Question 4: What does the endotoxin (pyrogen) test in sterile preparation quality control detect?
- Bacterial endotoxins (lipopolysaccharides from Gram-negative bacteria) that can cause fever and septic reactions (Correct answer)
- Viral contamination
- Fungal spores
- Particulate matter only
Correct answer: Bacterial endotoxins (lipopolysaccharides from Gram-negative bacteria) that can cause fever and septic reactions
Endotoxin (pyrogen) testing using the Limulus Amebocyte Lysate (LAL) assay detects Gram-negative bacterial endotoxins that survive sterilisation and can cause severe febrile reactions when injected.
Question 5: Why must cytotoxic drug preparation be performed in a negative pressure environment?
- To prevent hazardous drug aerosols from escaping the preparation area and exposing pharmacy staff (Correct answer)
- To maintain humidity for drug stability
- To increase drug potency
- To comply with temperature requirements only
Correct answer: To prevent hazardous drug aerosols from escaping the preparation area and exposing pharmacy staff
Negative pressure environments prevent hazardous aerosolised cytotoxic drug particles from being pushed out into the pharmacy, protecting staff from carcinogenic and mutagenic exposure.
Question 6: What is an 'expiry date' versus a 'beyond-use date' (BUD) in pharmacy compounding?
- Expiry date is assigned by the manufacturer; BUD is the date after which a compounded or opened preparation must not be used (Correct answer)
- They are the same concept
- BUD is always longer than the manufacturer's expiry date
- Expiry dates apply only to generics
Correct answer: Expiry date is assigned by the manufacturer; BUD is the date after which a compounded or opened preparation must not be used
Manufacturer-assigned expiry dates apply to commercially produced products; a beyond-use date is assigned by the pharmacist to compounded preparations or opened products based on stability data and storage conditions.
DHA Pharmacist Sterile & Non-Sterile Preparations 1
Which ISO cleanroom classification is required for the preparation of sterile injectable medications?