Bac water is bacteriostatic water — sterile water with 0.9% benzyl alcohol added as a preservative. The benzyl alcohol suppresses bacterial growth, so a multi-use vial stays usable for about 28 days after opening. In peptide research it is the standard diluent for reconstituting lyophilized compounds.
Everything here is for laboratory research use only. It describes bacteriostatic water and reconstitution arithmetic — not dosing, and not medical guidance. If your goal is treating something in yourself, that's a job for a licensed clinician.
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