Sterile water contains no preservative, so once opened it should be used immediately and discarded. Bacteriostatic water adds 0.9% benzyl alcohol, which lets the same vial be reused over roughly 28 days without bacterial growth. That reusability is why bac water is preferred for multi-use research peptide vials.
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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