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Bacteriostatic Water vs. Sterile Water: What's the Difference?
Choosing between bacteriostatic water and sterile water for injections or reconstituting peptides can affect safety and effectiveness. In this article, we'll compare the two, explain when to use each, and help you decide what’s best for your needs. If you're unfamiliar with the basics, start with what is bacteriostatic water?
What Is Bacteriostatic Water?
This type of water contains 0.9% benzyl alcohol as a preservative. It inhibits bacterial growth and is designed for multi-dose use, making it ideal for peptide reconstitution over several days or weeks.
What Is Sterile Water?
Sterile water is simply water that’s been purified and sterilized. It contains no preservatives and is meant for single-use only. Once opened, it must be discarded if not used immediately. See bacteriostatic water safety tips for multi-use guidance.
Main Differences
| Feature | Bacteriostatic Water | Sterile Water |
|---|---|---|
| Preservative | Yes (benzyl alcohol) | No |
| Intended Use | Multi-dose | Single-use |
| Shelf Life After Opening | 28 days | Immediate discard |
| Common Applications | Peptides, HRT, injections | IV dilution, wound cleaning |
When to Use Each
- Bacteriostatic Water: Ideal for multi-use peptide or hormone therapy vials
- Sterile Water: Better suited for one-time injections or clinical procedures
Wondering how long you can store each? Read about bacteriostatic water shelf life.
Both have their place in medicine, but for most injection-based therapies or peptide usage, bacteriostatic water is the preferred option due to its longer usability. Just ensure it hasn't expired and is sourced from a trusted provider.