A PHC pharmacist is arranging storage for diluent ampoules accompanying lyophilized BCG and MR vaccines. Which statement about diluent handling is correct?
- A Diluents should be stored in the deep freezer along with OPV to prolong shelf life
- B Diluents are heat labile and require storage colder than the vaccines they reconstitute
- C Diluents should be stored in the refrigerator at 2 to 8 degrees Celsius and must never be frozen ✓
- D Diluents may be stored at room temperature since they contain no biological material
Correct answer: C. Diluents should be stored in the refrigerator at 2 to 8 degrees Celsius and must never be frozen
Explanation
Diluents are cooled to 2 to 8 degrees Celsius so that reconstitution does not deliver a heat shock to the lyophilized vaccine, but freezing must be avoided because it cracks ampoules and can cause contamination. They are far more heat stable than vaccines themselves, so options A and B invert the real requirement, and room temperature storage defeats the purpose of matched cooling.
Reference: Park's Textbook of Preventive and Social Medicine, 25th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.