After opening, bacteriostatic water is generally considered good for about 28 days when refrigerated. The 0.9% benzyl alcohol suppresses bacterial growth over that window; after 28 days it should be discarded.
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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