Bacterostatic Water BAC Hospira BAC water is designed specifically for reconstituting peptides. The bacteriostatic agent (0.9% benzyl alcohol) helps inhibit bacterial growth, allowing for safe multi dose use. Quality matters here. Using a trusted, medical grade product Hospira: Lack of sterilisation confirmation triggers voluntary recall of Bacteriostatic Water for Injection DID YOU KNOW? Bacteriostatic Water contains 0.9% benzyl alcohol, which prevents bacteria from growing after the vial is opened. This makes it safe to use for up to 28 days once punctured