Bacteriostatic Water: Reconstitution Solution for Peptides
Bacteriostatic water is a sterile, non-pyrogenic solution containing 0.9% benzyl alcohol (9 mg/mL) that acts as a preservative to inhibit bacterial growth. It is commonly used for reconstituting medications and diluting injectable drugs intended for subcutaneous (SC), intramuscular (IM), or intravenous (IV) injection.
Unlike sterile water for injection, bacteriostatic water is designed for multi-dose use, allowing repeated withdrawals from a single vial for up to 28 days when properly stored.
Composition of Bacteriostatic Water
Sterile Water for Injection
0.9% Benzyl Alcohol (Preservative)
The benzyl alcohol prevents bacterial contamination, making it suitable for multi-dose vials and repeated medication preparation.
Uses of Bacteriostatic Water
Bacteriostatic water is widely used in medical, research, and veterinary environments for:
Reconstituting powdered or lyophilized medications
Diluting injectable drugs
Peptide reconstitution
Hormone preparation
Multi-dose medication protocols
Because it contains a preservative, it is often preferred when medications require multiple doses from the same vial.
Bacteriostatic Water vs. Sterile Water
Understanding the difference is important when selecting the appropriate diluent:
Sterile Water for Injection
Contains no preservatives
Intended for single-use only
Higher contamination risk after opening
Distilled Water
Purified through distillation
Not guaranteed sterile
Not suitable for injection
Bacteriostatic Water
Contains 0.9% benzyl alcohol
Safe for multi-dose use (up to 28 days after first puncture)
Reduces risk of bacterial growth
Safety Information
Bacteriostatic water is generally safe for injection when used as directed. However:
Not recommended for use in newborns or neonates due to potential benzyl alcohol toxicity
Should only be used under medical supervision
Always follow proper sterile handling procedures
Storage Guidelines
Store at controlled room temperature
Keep vial sealed and sterile
Discard 28 days after first use
Available Sizes and Packaging
Bacteriostatic water is commonly available in 30 mL multi-dose plastic vials from pharmaceutical manufacturers such as:
Pfizer
Hospira
It is frequently used in medical clinics, research laboratories, and veterinary practices where sterile medication preparation is required.
