What method is commonly employed to verify the effectiveness of sterilization?

The effectiveness of sterilization is most commonly verified through sterility testing, particularly USP 71 sterility testing. This method is designed to assess whether a compounded sterile preparation (CSP) is free from viable microorganisms. The procedure involves incubating samples from the CSP in a nutrient-rich medium suitable for microbial growth and monitoring for any signs of microbial contamination over a defined period. If no growth is detected, it indicates that the sterilization process was effective.

Microbial load testing, while it assesses the presence and quantity of microorganisms in a sample, does not specifically evaluate the effectiveness of the sterilization process itself. Similarly, physical examination of CSPs can confirm the integrity and appearance of the preparation but does not provide definitive evidence regarding the absence of microorganisms. Chemical analysis focuses on the composition and concentration of the components within a preparation, which, although important, does not provide direct information about sterility.

Thus, USP 71 sterility testing stands out as the most reliable method for specifically verifying that a CSP has been successfully sterilized.