Scientific Reference
Bacteriostatic Water
Evidence profile: Component evidence only — this formulation has not itself been studied
This is a diluent chosen for containers that get opened more than once. It is sterile water with 0.9% benzyl alcohol added as a preservative, and the preservative is there to slow the growth of any bacteria introduced on a second or third access — which is the only reason to prefer it to plain sterile water. It is worth being clear about what it is not: it is not an antiseptic, and it will not make an already-contaminated solution sterile. Benzyl alcohol is also not compatible with every material, and some peptides and proteins are sensitive to it, which is why plain sterile water and dilute acids remain in laboratory use beside it. It is a supply, not a research compound, and contributes no pharmacology to the work it accompanies.
Mechanism of Action
Benzyl alcohol (C6H5CH2OH) is a simple aromatic alcohol, and at this concentration its effect is bacteriostatic rather than bactericidal — it holds back the multiplication of many bacteria rather than dependably killing them. The action is generally attributed to disruption of microbial cell membranes, raising their permeability and interfering with enzymes bound to them. The water is doing nothing but dissolving. Because inhibiting growth is not the same as sterilising, the solution decontaminates nothing that was already contaminated, and it adds no pharmacological activity of its own to whatever it dilutes.
Molecular Information
- Type: Solvent (bacteriostatic aqueous solution)
Published Research
Antimicrobial Preservatives for Protein and Peptide Formulations: An Overview
Stroppel L et al. · Pharmaceutics · 2023 · Review · Evidence for Benzyl alcohol (bacteriostatic preservative)
PMID 36839885 — View on PubMedCritical Aspects of pH Measurement for Bacteriostatic Water for Injection
Hu J et al. · Journal of pharmaceutical sciences · 2023 · Preclinical · Evidence for Benzyl alcohol (bacteriostatic preservative)
PMID 36870668 — View on PubMedMolecular Mechanism of Antimicrobial Excipient-Induced Aggregation in Parenteral Formulations of Peptide Therapeutics
Li M et al. · Molecular pharmaceutics · 2022 · Preclinical · Evidence for Benzyl alcohol (bacteriostatic preservative)
PMID 35917158 — View on PubMedComplex poisoning mainly with benzyl alcohol complicated by paralytic ileus: a case report
Fukuda H et al. · International journal of emergency medicine · 2022 · Preclinical · Evidence for Benzyl alcohol (bacteriostatic preservative)
PMID 35787785 — View on PubMedIncompatibility of ifosfamide with benzyl-alcohol-preserved bacteriostatic water for injection
Behme RJ et al. · American journal of hospital pharmacy · 1988 · Preclinical · Evidence for Benzyl alcohol (bacteriostatic preservative)
PMID 3369469 — View on PubMed