How to Store Bacteriostatic Water Safely Confused about whether BAC water needs refrigeration after opening? According to USP standards and Pfizer's own guidance, both room temp (2025C) and refrigeration are acceptable How to Store Bacteriostatic Water Safely Confused about whether BAC water needs refrigeration after opening? According to USP standards and Pfizer's own guidance, both room temp (2025C) and refrigeration are acceptable BAC Water 30ml Large Bottle Reconstituting a peptide the right way = better stability, better results, and safer handling. Here are the non negotiables I teach every client before they start: Clean setup first: wash hands + How Long Does Bac Water Last in the Fridge? An Expert Breakdown