Bacteriostatic water for injection is sterile water used in healthcare settings. It serves as a diluent for various injectable medications. This preparation maintains the sterility and integrity of drug solutions over a limited period after initial use.
Understanding Bacteriostatic Water for Injection
Bacteriostatic water for injection is sterile water meeting United States Pharmacopeia (USP) purity standards. It differs from plain sterile water by including a bacteriostatic agent, typically 0.9% benzyl alcohol. This additive inhibits the growth and reproduction of most common bacteria within the solution.
The term “bacteriostatic” means the agent prevents bacteria from multiplying, rather than actively destroying them. This property maintains the water’s quality once its container has been accessed, ensuring it remains suitable for use over time.
Its primary function is to serve as a solvent or diluent for powdered or concentrated medications prepared for injection. It is intended for parenteral use, facilitating administration via intravenous, intramuscular, or subcutaneous routes. This ensures medications can be safely diluted to the correct concentration before patient administration.
The Purpose of Bacteriostatic Water for Injection
The benzyl alcohol in bacteriostatic water allows multi-dose use of a single vial after puncture. This enables healthcare providers to draw multiple doses without immediate concern for bacterial contamination. The preservative suppresses bacterial proliferation from repeated needle entries.
This enhances convenience and reduces waste, as an entire vial does not need discarding after one use. Once opened, benzyl alcohol typically maintains effectiveness for up to 28 days. This extended usability makes bacteriostatic water practical for medications requiring reconstitution and multi-day use.
Bacteriostatic water is not for direct injection without a dissolved medication. Its sole purpose is to dilute or dissolve drugs, creating a solution for safe administration. The specific medication’s instructions dictate the appropriate diluent and preparation method.
Practical Use and Storage
When preparing medications, bacteriostatic water reconstitutes powdered drugs or dilutes concentrated liquid formulations. The process involves sterile technique, including swabbing vial tops with alcohol and using a new, sterile syringe and needle for each withdrawal. Gently injecting the water into the medication vial and swirling, rather than shaking, ensures the drug dissolves properly without degradation or foaming.
After reconstitution, the medication is ready for administration via the intended injection route, such as intramuscular or subcutaneous injection. Proper storage maintains bacteriostatic water’s integrity. Unopened vials should be stored at room temperature, typically 20-25°C (68-77°F), and kept away from light.
Once punctured, a bacteriostatic water vial’s shelf life becomes limited. It should be used within 28 days, unless specific drug manufacturer instructions state otherwise. Label the vial with the date of first entry to track expiration. Discard any solution that appears cloudy, discolored, or contains visible particles, as these indicate potential contamination or degradation.