Bacteriostatic Sterile Water for Injection USP is sterile water that contains a bacteriostatic agent, often benzyl alcohol, which inhibits the growth of most potentially contaminating bacteria. It's used as a diluent to prepare injectable medications.

Here are some key points to consider:

1. Usage: It's used to dilute or dissolve drugs for injection. The bacteriostatic agent helps ensure that the solution remains sterile once it's been opened and used for the first time, over its usability period.

2. Benzyl Alcohol: Most bacteriostatic water contains 0.9% benzyl alcohol as a preservative. However, this agent is not suitable for all patients. Specifically, it shouldn't be used in neonates or infants because it can be associated with toxicity in this population. Always ensure that the solution is appropriate for the intended patient population.

3. Storage: Store at room temperature and keep away from light. Once opened, there's typically a limit to how long you can use it. After this time, even if there's still some left in the vial, it should be discarded to ensure sterility.

4. Single-patient Use: Even though it contains a bacteriostatic agent, it's generally designed for single-patient use. This means that once you've used it for one patient, you shouldn't use it for another, even if you're using a new, sterile needle and syringe.

5. Not for All Drugs: Some drugs should not be mixed with bacteriostatic water due to compatibility issues. Always refer to the specific drug's prescribing information to determine the appropriate diluent.

6. Comparatively to Sterile Water: Sterile water without the bacteriostatic agent is a single-use item. Once opened, it should be used immediately and then discarded. It doesn't contain any antimicrobial agents, so there's a risk of bacterial contamination if it's not used immediately.

Remember, always consult with a pharmacist or another healthcare professional if you have questions about medication preparation, administration, or storage.