Bacteriostatic Water

Bacteriostatic water is sterile water for injection with 0.9% benzyl alcohol added as preservative. The benzyl alcohol inhibits bacterial growth - hence "bacteriostatic" - and allows multiple withdrawals from the same vial over about 28 days.

It is the standard diluent used to reconstitute lyophilized (freeze-dried) peptides before injection. Without bac water the peptide stays as dry powder and cannot be injected.

The standard process in five steps:

1. Bring both vials (peptide and bac water) to room temperature.
2. Draw the desired amount of bac water with a sterile insulin syringe (typically 2-3ml for a 5mg vial).
3. Insert the needle into the peptide vial and add the bac water - it does not matter if it hits the powder directly, that is a myth.
4. Swirl or shake the vial until everything dissolves - both are fine, the old no-shaking rule is a myth.
5. Wait until the solution is fully clear (1-2 minutes).

The amount of bac water determines the concentration. More water = lower concentration per unit on the syringe, less water = higher concentration.

• Unopened: stable at room temperature until the printed expiry date.
• Opened (vial punctured): 28 days at room temperature per standard guidance.
• Reconstituted peptide: refrigerated, stable for at least 4 to 6 months with barely any loss of potency, in practice considerably longer.

Never freeze - it destroys the peptide structure. Keep protected from light.

Two related products often confused:

• Bacteriostatic water: with 0.9% benzyl alcohol. Multi-use possible. Standard for most peptides.
• Sterile water for injection: no preservative. Single-use only. Needed for rare applications (e.g. infants or specific clinical procedures).

For standard peptide reconstitution: always bacteriostatic water.

We only ship as much bacteriostatic water as your reconstitution-required vials actually need - calculated at a maximum of 3ml per vial. Bacteriostatic water therefore cannot be bought "in stock". That is exactly why our automated system always adds the right amount to your cart when you order.

The same applies to single vials: 3ml per vial is included. If you order, say, 30ml but only have 5 vials, you receive 15ml - the difference is credited to your account as balance.

• Use a fresh sterile syringe every time, never reuse.
• Disinfect the vial septum with an alcohol swab before each withdrawal.
• Watch for a clear solution - discard if cloudy or discolored.
• Store out of reach of children.