Hospira Bacteriostatic Water for Injection, USP is a sterile, nonpyrogenic preparation designed to serve as a diluent or solvent for certain medications that require dilution or dissolution before parenteral administration. Hospira, now part of Pfizer's pharmaceutical operations, supplies the product in multidose vial formats containing benzyl alcohol as a bacteriostatic preservative.

Unlike ordinary sterile water, bacteriostatic water contains a preservative that helps inhibit the growth of microorganisms after repeated withdrawals from a multidose container. However, that does not mean the product can substitute for every injectable diluent or medication. The prescribing information for the specific drug being prepared determines which diluent is appropriate.

What Is Hospira Bacteriostatic Water?

Hospira Bacteriostatic Water for Injection, USP contains Water for Injection and benzyl alcohol. The current DailyMed labeling identifies Hospira, Inc. as the packager and lists the product as a human prescription drug. The preparation is intended for parenteral use only after an appropriate drug has been added for dilution or dissolution.

The product itself is not a medication used to treat a disease. Instead, it functions as a pharmaceutical aid. A healthcare professional may use an appropriate diluent when a particular injectable drug's manufacturer specifies bacteriostatic water as a compatible vehicle.

The formulation has a pH of approximately 5.7, with a labeled range of 4.5 to 7.0. The water is sterile and nonpyrogenic, while benzyl alcohol provides the bacteriostatic preservative function.

Because different medications have different chemical and physical requirements, users should never assume that bacteriostatic water is compatible with an injectable drug simply because both products are intended for parenteral use.

What Makes Bacteriostatic Water Different From Sterile Water?

The key difference is the presence of a preservative.

Sterile Water for Injection does not contain a bacteriostatic preservative, while Hospira Bacteriostatic Water for Injection contains benzyl alcohol. The Hospira label specifically identifies benzyl alcohol concentrations of either 0.9% (9 mg/mL) or 1.1% (11 mg/mL), depending on the presentation.

This distinction matters because the preservative affects how the product can be used. Bacteriostatic water is supplied in a multidose container from which repeated withdrawals may be made, subject to appropriate sterile handling and the applicable product instructions.

Sterile Water for Injection and bacteriostatic water therefore should not be treated as interchangeable products. The medication manufacturer's instructions should always determine which diluent to use.

Why Does Hospira Bacteriostatic Water Contain Benzyl Alcohol?

Benzyl alcohol serves as the bacteriostatic preservative in this formulation. Its inclusion helps limit microbial growth in the multidose container when the product is handled according to its labeling.

Hospira currently lists two relevant presentations: a 30 mL multidose plastic vial containing 9 mg/mL of benzyl alcohol and a 20 mL fill in a 30 mL glass vial containing 11 mg/mL.

The presence of benzyl alcohol also creates an important safety consideration. Hospira's labeling carries a clear warning that the product is not for use in neonates. Healthcare professionals must also consider whether the preservative is appropriate for the intended patient and medication.

This is one reason a healthcare professional should select the diluent rather than relying on the product name alone.

What Is Hospira Bacteriostatic Water Used For?

The primary role of this product is pharmaceutical dilution or dissolution. The official labeling states that it is designed for use after adding drugs that require dilution or must be dissolved in an aqueous vehicle before injection.

The correct amount and method depend entirely on the medication being prepared. The Hospira labeling explains that the volume used depends on factors such as the drug concentration, dose, vehicle, and administration route specified by the drug manufacturer.

For that reason, there is no universal “Hospira bacteriostatic water dosage.” The water itself does not establish the dose of the medication.

Examples of factors that a healthcare professional may need to verify include:

• Whether the medication specifically permits bacteriostatic water
• The required diluent volume
• The desired final concentration
• The intended route of administration
• Compatibility and stability after preparation
• Patient-specific contraindications or precautions

Never use a diluent based solely on an online recommendation when the medication's official prescribing information specifies a different vehicle.

Hospira Bacteriostatic Water Presentations

Pfizer Medical's current product information lists two Hospira presentations with different benzyl alcohol concentrations.

30 mL multidose vial: This presentation contains 9 mg/mL of benzyl alcohol and is supplied as a multidose plastic flip-top vial.

20 mL fill in a 30 mL glass vial: This presentation contains 11 mg/mL of benzyl alcohol and uses a glass flip-top vial.

The product labeling identifies these presentations with specific National Drug Codes (NDCs). Packaging and availability can change, so purchasers and healthcare facilities should verify the current NDC, manufacturer information, vial size, and label before use.

How Should Hospira Bacteriostatic Water Be Stored?

The labeled storage condition for Hospira Bacteriostatic Water is 20°C to 25°C (68°F to 77°F), consistent with USP controlled room temperature guidance.

Proper storage helps maintain product quality, but storage alone cannot compensate for compromised packaging or poor handling. Before use, healthcare personnel should inspect the container and solution according to the manufacturer's instructions.

The solution should not be used if the container is damaged, the seal is compromised, or the solution shows inappropriate particulate matter or discoloration. Parenteral products should be visually inspected before administration whenever the container and solution permit.

Important Safety Warnings and Precautions

Hospira Bacteriostatic Water is an injectable pharmaceutical product, so sterile technique and professional judgment matter.

The most prominent labeling warning states that the product is not for use in neonates because it contains benzyl alcohol.

Another important point is that bacteriostatic water is intended as a drug diluent rather than as a standalone therapeutic injection. The label specifically describes it as being for drug diluent use only.

Healthcare professionals should also verify the compatibility of the diluent with the medication. Some drugs require a particular solvent or diluent because changes in pH, concentration, stability, or excipients can affect the final preparation.

Patients should not independently select a diluent, calculate injectable medication concentrations, or prepare prescription injections based on general internet instructions. The medication's official prescribing information and instructions from a qualified healthcare professional should take precedence.

Hospira Bacteriostatic Water vs. Sterile Water: Which One Is Appropriate?

The answer depends on the medication.

Bacteriostatic water contains benzyl alcohol and is supplied in multidose presentations. Sterile Water for Injection does not contain a bacteriostatic preservative. Because those formulations differ, the choice should come from the drug manufacturer's approved preparation instructions.

A medication that specifies Sterile Water for Injection should not automatically be prepared with bacteriostatic water. Conversely, a drug that specifically permits bacteriostatic water may require the preservative-containing formulation for its intended preparation.

Pharmacists, nurses, physicians, and other qualified professionals can verify compatibility using the medication's prescribing information, institutional protocols, and authoritative drug references.

How to Verify a Hospira Bacteriostatic Water Product

Before purchasing or using a product, check the label rather than relying only on a retailer's product description.

Look for:

• Manufacturer or distributor: Hospira/Pfizer information
• Product name: Bacteriostatic Water for Injection, USP
• Benzyl alcohol concentration: 0.9% or 1.1%, depending on presentation
• Vial size and configuration
• NDC number
• Lot number and expiration date
• Container integrity
• Storage requirements

The current DailyMed entry provides official labeling information and lists Hospira's NDCs and product details. Pfizer Medical also provides current information about Hospira's supplied presentations.

Frequently Asked Questions

Is Hospira Bacteriostatic Water the same as sterile water?

No. Hospira Bacteriostatic Water contains benzyl alcohol as a bacteriostatic preservative, while Sterile Water for Injection does not contain a bacteriostatic preservative. The appropriate product depends on the medication being prepared.

What is Hospira Bacteriostatic Water used for?

It is used as a diluent or solvent for certain drugs that require dilution or dissolution before parenteral administration. It is not intended to serve as a standalone therapeutic medication.

Does Hospira Bacteriostatic Water contain benzyl alcohol?

Yes. Hospira lists presentations containing 9 mg/mL or 11 mg/mL of benzyl alcohol, depending on the vial configuration.

Can bacteriostatic water be used with any injectable medication?

No. Compatibility varies by medication. Always follow the specific drug manufacturer's prescribing information and professional preparation guidance.

Is Hospira Bacteriostatic Water safe for newborns?

The Hospira labeling specifically warns that this product is not for use in neonates because it contains benzyl alcohol.

How should Hospira Bacteriostatic Water be stored?

The labeled storage temperature is 20°C to 25°C (68°F to 77°F), under USP controlled room temperature conditions.

Is Hospira Bacteriostatic Water prescription-only?

The current DailyMed labeling identifies the Hospira product as a human prescription drug and the package labeling states “Rx only.”