Water for injections 5ml

Water for Injections 5ml (Bacteriostatic) for sale in the UK

Water for Injections 5ml is a pharmaceutical-grade bacteriostatic water presented as a multi-use vial preserved with 0.9% benzyl alcohol. It is the standard solvent used to reconstitute lyophilised (freeze-dried) peptides, growth hormone, HCG and IGF-1 for subcutaneous or intramuscular injection. If you want to buy bacteriostatic water UK from a verified source, every vial sold here is dispatched same working day from our UK warehouse.

What is bacteriostatic water?

Bacteriostatic water for injection is sterile water containing 0.9% benzyl alcohol — a preservative that inhibits the growth of most common bacteria. The "bacteriostatic" qualifier is what allows the same vial to be drawn from repeatedly: under USP guidelines, a sealed vial of bacteriostatic water remains usable for up to 28 days after first puncture when stored refrigerated. By contrast, plain sterile water for injection contains no preservative and is intended for single use only — once punctured, any unused volume must be discarded. For users reconstituting an HGH or peptide vial that will be drawn from over several weeks, bacteriostatic water is the correct solvent. The benzyl alcohol is present at a low enough concentration that it has no effect on the activity of HGH, HCG, IGF-1 LR3 or standard research peptides.

Bacteriostatic water uses

• Reconstituting lyophilised growth hormone vials (e.g. somatropin)
• Reconstituting HCG ampoules and pre-filled HCG vials
• Reconstituting IGF-1 LR3, IGF-1 DES and research peptides
• Diluting injectable solutions where multi-day vial use is required
• Any application where a sealed vial will be accessed multiple times over up to 28 days

The 5 ml format gives enough volume for several reconstitutions, which is why it is the most common size kept on hand by users running HGH, peptide or fertility-protocol cycles.

Bacteriostatic vs sterile water — which to use

Use bacteriostatic water (this product) when the reconstituted vial will be drawn from more than once — for example, a 100 IU HGH vial used over 7–14 days, or an HCG vial dosed twice weekly. Use sterile water when the reconstituted dose will be drawn and injected immediately and any remainder discarded — for example, single-use HCG before a fertility procedure. For most performance and TRT-adjacent use cases, bacteriostatic is the correct choice.

Storage and shelf life

Store sealed vials at room temperature, away from direct sunlight. Once the rubber stopper has been punctured, store refrigerated (2–8 °C) and discard any remaining solution after 28 days. Always wipe the stopper with an alcohol swab before drawing, and use a fresh sterile needle each time.

Pairs well with

Bacteriostatic water is essential alongside lyophilised compounds such as Qomatropin HGH 100IU, HCG 5000IU and IGF-1 LR3. Pair with our syringe, needle and swab package for a complete reconstitution kit. If you only need single-use solvent, see Water for Injections 2ml (sterile).

Frequently asked questions

What is the difference between bacteriostatic and sterile water for injection?

Sterile water is preservative-free and intended for single use — any unused volume must be discarded once the vial is opened. Bacteriostatic water contains 0.9% benzyl alcohol, which inhibits bacterial growth and allows the same vial to be drawn from for up to 28 days post-puncture when refrigerated. Use bacteriostatic water for multi-dose reconstitution of HGH, HCG and peptides.

How long does bacteriostatic water last after first puncture?

Up to 28 days when stored refrigerated at 2–8 °C with the rubber stopper intact and wiped with an alcohol swab before each draw. After 28 days, discard any remaining solution and use a fresh vial. The 28-day window is set by USP guidance based on the antimicrobial activity of the benzyl alcohol preservative.

Why does benzyl alcohol matter?

Benzyl alcohol at 0.9% is the bacteriostatic agent that prevents bacterial colonisation of the vial between draws. Without it, repeated needle access would risk contamination. The concentration is low enough that it does not denature recombinant proteins like HGH or IGF-1, and it has no clinically meaningful effect on the reconstituted compound's activity.