CPhT Compounding 3 — Questions and Answers
Question 1: Under USP <797>, which category of compounded sterile preparations (CSPs) has a permitted BUD of up to 45 days?
- Category 1 CSPs
- Category 2 CSPs stored at room temperature
- Category 2 CSPs stored at controlled cold temperature (Correct answer)
- Immediate-use CSPs
Correct answer: Category 2 CSPs stored at controlled cold temperature
Category 2 CSPs stored at controlled cold temperature (2–8 °C) may have a BUD of up to 45 days per USP <797> (2023 revision).
Question 2: Which ISO classification is required for the direct compounding area (DCA) when preparing sterile CSPs under a laminar airflow workbench (LAFW)?
- ISO Class 4
- ISO Class 5 (Correct answer)
- ISO Class 7
- ISO Class 8
Correct answer: ISO Class 5
The direct compounding area inside a LAFW must maintain ISO Class 5 (≤100 particles ≥0.5 µm per cubic foot).
Question 3: A technician adds 10 mL of a 50% dextrose solution to 90 mL of sterile water for injection. What is the final dextrose concentration?
- 5% (Correct answer)
- 10%
- 25%
- 45%
Correct answer: 5%
Dextrose mass = 10 mL × 0.50 = 5 g; final volume = 100 mL; concentration = 5 g/100 mL = 5%.
Question 4: When compounding a sterile preparation, which action BEST prevents touch contamination?
- Using a horizontal laminar airflow workbench
- Keeping gloved hands downstream of critical sites (Correct answer)
- Wearing a surgical mask
- Performing a media-fill test monthly
Correct answer: Keeping gloved hands downstream of critical sites
Keeping hands downstream (between the HEPA filter and the critical site) ensures unidirectional airflow sweeps over the critical site without contamination from hands.
Question 5: What is the purpose of a media-fill test in a sterile compounding pharmacy?
- To verify the potency of compounded preparations
- To qualify personnel aseptic technique using a microbial growth medium in place of the drug (Correct answer)
- To test the sterility of final CSPs before dispensing
- To measure particulate matter in the ISO 5 zone
Correct answer: To qualify personnel aseptic technique using a microbial growth medium in place of the drug
Media-fill tests simulate the compounding process using trypticase soy broth to assess whether a compounder's technique introduces microbial contamination.
Question 6: Amphotericin B for injection must NOT be reconstituted with normal saline because:
- Saline raises the pH beyond stability limits
- Electrolytes cause the colloidal dispersion to precipitate (Correct answer)
- Saline accelerates oxidation of the drug
- The osmolarity becomes too high for IV administration
Correct answer: Electrolytes cause the colloidal dispersion to precipitate
Amphotericin B forms a colloidal dispersion that precipitates in the presence of electrolytes like sodium chloride.
Question 7: Which statement about closed-system transfer devices (CSTDs) is correct?
- CSTDs are required for all sterile compounding
- CSTDs are primarily used to prevent environmental release of hazardous drugs (Correct answer)
- CSTDs eliminate the need for a biological safety cabinet
- CSTDs must be cleaned with IPA before every transfer
Correct answer: CSTDs are primarily used to prevent environmental release of hazardous drugs
CSTDs mechanically prohibit the transfer of environmental contaminants into the system and the escape of hazardous drug vapors or aerosols outside the system.
CPhT Compounding 3
Under USP , which category of compounded sterile preparations (CSPs) has a permitted BUD of up to 45 days?