Bacteriostatic Water
That Won't Ruin Your Peptide
Most cloudy-vial complaints trace back to one cause: the bac water. We source pharmaceutical-grade, USP-spec bacteriostatic water in 30ml multi-dose vials — verified by COA on every batch.
Why bac water quality matters
If you've ever reconstituted a peptide and watched the solution turn cloudy, the bac water is almost always the cause. Bad bac water doesn't just look wrong — it actively degrades the peptide.
⚠ What bad bac water does
- • Sub-spec benzyl alcohol fails to preserve the vial past 7-14 days, allowing microbial growth
- • pH drift outside 4.5-7.0 breaks peptide bonds, irreversibly denaturing the molecule
- • Counterfeit / repackaged vials on marketplaces sometimes contain plain saline mislabeled
- • Cloudy reconstitution = peptide aggregation. You're injecting clumped, inactive protein
- • Microbial contamination introduces protein-degradation enzymes that ruin the vial overnight
✓ What our bac water guarantees
- • 0.9% benzyl alcohol — full USP spec for multi-dose preservation through the 28-day window
- • pH 5.7 ± 0.2 — within the safe range for every peptide and GLP-1 we've tested
- • cGMP-manufactured in an FDA-registered facility, batch-traced
- • Certificate of Analysis on every production lot, available before you buy
- • Sterile multi-dose 30ml vial — reconstitutes 10-15 typical peptide vials at the standard 2-3ml ratio
Product specs
| Volume | 30 mL multi-dose vial |
| Preservative | 0.9% benzyl alcohol (USP-spec) |
| pH | 5.7 ± 0.2 |
| Sterility | USP 71 / 797 protocol |
| Manufacturing | FDA-registered cGMP facility |
| Quality verification | Independent lab COA per lot |
| Shelf life unopened | 24 months |
| Shelf life opened | 28 days refrigerated |
| Shipping | USPS Priority — ships next business day, US-only |
| Cost per vial | $25 list — $21.25 with code thepeptidecatalog15 |
Common questions
What can I use this bac water for?+
Reconstituting research peptides, compounded GLP-1s (semaglutide, tirzepatide, retatrutide), HRT injectables, B12, and any other multi-dose injectable that calls for bacteriostatic water. The benzyl alcohol preservative keeps the vial sterile for up to 28 days after first puncture when refrigerated.
How much do I need per peptide vial?+
Typical reconstitution uses 2-3 mL of bac water per peptide vial. A single 30 mL bottle therefore covers 10-15 peptide vials, which is usually enough for a full 6-12 week cycle depending on dosing protocol.
What's the difference between bacteriostatic water and sterile water?+
Sterile water has no preservative — once the seal is broken, you have hours of safe use, not days. Bacteriostatic water adds 0.9% benzyl alcohol, which prevents bacterial growth for up to 28 days. For multi-dose peptide vials, you want bacteriostatic.
Is bac water prescription-only?+
Per the FDA label, bacteriostatic water for injection is technically Rx-only and intended for professional/research use. We ship to research customers and self-administered patients. Check your jurisdiction's requirements; we don't ship internationally.
Why is it priced higher than Amazon listings?+
Most cheap Amazon bac water doesn't include a published COA, isn't cGMP-manufactured, or is repackaged from unknown sources. The difference shows up in peptide vial stability. We publish a Certificate of Analysis on every batch — the kind of verification that justifies a $5-10 premium over the cheapest available option.
Can I see a COA before I buy?+
Yes. Every batch has a publicly downloadable Certificate of Analysis. Reach out at hello@bacwatercatalog.com if you'd like the lot-specific COA before your order ships.
Ready to reconstitute with confidence?
30ml USP bacteriostatic water — $25, or $21.25 with code thepeptidecatalog15. Ships next business day.
Buy 30ml Vial — $21.25