Glossary
Bacteriostatic Water
Sterile water containing 0.9% benzyl alcohol as a preservative, used to reconstitute peptides for multi-dose injectable use.
Also known as:
BAC water bac-water bacteriostatic
The benzyl alcohol in bacteriostatic water inhibits bacterial growth, making it safe to draw from the same vial multiple times over several weeks — unlike plain sterile water which should only be used once. This multi-dose property makes it the standard solvent for reconstituting research peptides.
Bacteriostatic water is available at pharmacies (often without prescription) and online. It is distinct from saline, sodium chloride for injection, and plain sterile water — substitutions can affect peptide stability or cause irritation at the injection site.