Bac water Hospira is bacteriostatic water for injection, USP, from Pfizer's Hospira line. Compare 10mL vs 30mL vials, storage rules, and safety.
Bac water Hospira is a multi-dose vial of Bacteriostatic Water for Injection, USP — sterile water with 0.9% benzyl alcohol added as a preservative. Hospira is the injectable-medicine business that Pfizer acquired in 2015, and its bacteriostatic water is one of the most widely recognized diluents sold to US clinics, pharmacies, and laboratories. It is a diluent, not a drug: its only job is to dissolve or dilute compatible medications and research compounds.
Most people searching for this product need a preservative-containing diluent instead of a single-use vial of plain sterile water. Knowing what the vial contains, how long it stays usable, and how it is legally sold matters more than the brand name on the carton.
What Is Inside a Hospira Bacteriostatic Water Vial?
The USP monograph for Bacteriostatic Water for Injection sets the formula: sterile water for injection plus 0.9% benzyl alcohol, which works out to roughly 9 mg of benzyl alcohol per milliliter. That preservative is what allows a multi-dose vial to be punctured repeatedly without every entry introducing contamination.
The 0.9% benzyl alcohol in Hospira bacteriostatic water is a preservative, not an active drug ingredient. Plain sterile water for injection contains no preservative, so once a single-dose vial is opened it must be used right away or thrown out.
Because Hospira now operates under Pfizer, some distributor listings appear as pfizer hospira bac water. The current carton still reads Hospira, and vials ship in boxes of 10 or 25 depending on the fill size.
Hospira 10 mL vs 30 mL Vials
| Feature | 10 mL vial | 30 mL vial |
|---|---|---|
| Total volume | 10 mL | 30 mL |
| Benzyl alcohol | 0.9% (9 mg/mL) | 0.9% (9 mg/mL) |
| Vial type | Sterile, multi-dose | Sterile, multi-dose |
| Best suited to | Short protocols, single patient | Frequent reconstitution, shared lab use |
| Typical US price per vial | $5 to $15 | $8 to $25 |
The smaller size, commonly listed as hospira bac water 10ml, fits short protocols or single-patient use, while the larger format is more economical for labs that reconstitute powders often. Both sizes contain the same 0.9% benzyl alcohol concentration, so the real decision is about volume and how quickly you will use it.
What Bacteriostatic Water Is Used For
In clinical practice, bacteriostatic water is used to reconstitute powdered medications and to dilute compatible injectables that will be withdrawn more than once. In laboratory work, it is used to dissolve lyophilized powders so the resulting solution can be drawn in small, repeatable aliquots.
In research settings, people searching for bac water for peptides usually want a multi-dose diluent they can draw from across several sessions without the sterility concerns of a single-use vial. The phrase bac water for injection describes the same product category: a water-based diluent intended to be added to a powder or liquid before administration or testing.
- Reconstituting lyophilized powders into a usable solution
- Diluting compatible medications for multi-dose withdrawal
- Preparing reference solutions in research workflows
- Rinsing and preparing non-clinical lab equipment
Bacteriostatic water is not a substitute for saline or for a manufacturer's specified diluent when a drug label names one. Follow the instructions that come with the medication or compound you are working with.
Bacteriostatic Water vs Sterile Water
| Feature | Bacteriostatic water | Sterile water for injection |
|---|---|---|
| Preservative | 0.9% benzyl alcohol | None |
| Vial type | Multi-dose | Single-dose |
| Use after first puncture | Limited in-use window (often 28 days) | Use immediately, discard the remainder |
| Newborn and neonatal use | Contraindicated | Acceptable when clinically indicated |
| Best suited to | Repeated withdrawals from one vial | One-time dilution |
Bacteriostatic water should never be used when a drug label calls for plain sterile water, and sterile water should not be treated as a multi-dose replacement when a preservative is needed.
Storage, Shelf Life, and Handling
- Store unopened vials at 20 to 25 °C (68 to 77 °F); USP controlled room temperature allows brief excursions to 15 to 30 °C.
- Do not freeze the vials. Freezing can crack the glass and does not improve stability.
- After the first puncture, many facilities apply a 28-day in-use limit, and Hospira labeling directs users to discard unused portions.
- Swab the rubber stopper with alcohol before each withdrawal, and never leave a needle sitting in the stopper.
- Write the puncture date on the vial so the discard date is obvious at a glance.
Unopened Hospira vials typically carry an expiration date 18 to 24 months out from manufacture, printed on both the carton and the vial label.
Safety Warnings and Legal Status
Bacteriostatic Water for Injection, USP is a prescription product in the United States, not an over-the-counter item. It is sold to licensed healthcare organizations, pharmacies, and laboratories, and US-labeled Hospira cartons carry "Rx only."
Benzyl alcohol is not harmless in every population. The label warns against use in newborns and premature infants, where benzyl alcohol exposure has caused severe respiratory and metabolic reactions, and intrathecal use is prohibited.
- Not for newborns, premature infants, or neonates
- Not for intrathecal or epidural use
- Not for large-volume hydration
- Not for standalone intravenous use
- Not a treatment for any medical condition
Benzyl alcohol–containing diluents are contraindicated in neonates, and any use in a patient should follow the prescribing instructions for the medication being reconstituted.
Sourcing and What It Costs
Hospital pharmacies, national medical distributors, and research supply companies are the standard channels for this product. If you are trying to figure out where to buy bac water, look for a supplier that ships US-labeled Hospira stock with a lot number and expiration date on the carton and that verifies licensed accounts where required.
Typical US pricing runs about $8 to $25 for a single 30 mL vial and $5 to $15 for a 10 mL vial, though case pricing lowers the per-vial cost significantly. Unusually cheap listings from overseas sellers are a common sign of unlabeled, repackaged, or improperly stored product.
Hospira bacteriostatic water is a prescription-only medical supply in the United States, and it is not regulated or sold as a dietary supplement.
Anyone considering this product for personal use should speak with a pharmacist or licensed clinician first, especially if a newborn, an immunocompromised person, or a prescribed injectable medication is involved.
Frequently Asked Questions
Is Hospira bac water the same as bacteriostatic water?
Yes. "Bac water" is common shorthand for Bacteriostatic Water for Injection, USP, and Hospira is one of the manufacturers that produces it under that name. The Hospira product contains 0.9% benzyl alcohol as a preservative and comes in multi-dose vials. Other manufacturers make equivalents, though fill volumes and labeling can differ.
How long is Hospira bac water good after the first puncture?
Hospira labeling directs users to discard unused portions, and most healthcare facilities apply a 28-day in-use limit once a multi-dose vial is first entered. Write the puncture date on the vial and follow your facility or pharmacist's policy. Unopened vials should be kept at controlled room temperature and never frozen.
Can I buy Hospira bac water without a prescription in the US?
Bacteriostatic Water for Injection, USP is a prescription product in the United States, so US-labeled Hospira vials are sold through licensed medical distributors and pharmacies rather than general retail. Sellers that ship it openly to consumers with no verification are usually offering unlabeled or imported product. A pharmacist can clarify whether it is appropriate for your situation.
This page provides educational research information and does not replace medical advice, diagnosis, or treatment.