Uses of Bacteriostatic Water for Injections and Where to Get It 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 CANLABS: Does BAC Water Expire? Have had for a year in fridge. : r Peptides Bacteriostatic water for injection Bac water Free shipping Bottled water often carries an expiration or best by date, but pure water itself does not expire or spoil, as it lacks nutrients for bacteria growth. The date primarily concerns the plastic bottle: