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Bac water bulk usually means bacteriostatic water bought in quantity, but “bulk” is not a label term for that product. On the Hospira (Pfizer) label, bacteriostatic water is a multiple-dose vial supplied in trays of 25. In USP, “pharmacy bulk package” is a different thing: a container of many single doses for pharmacy admixture. This page separates the two and lists what a label or supplier record can and cannot show. It is general product information, not medical advice.
Short answer
Bacteriostatic water for injection is sterile water with benzyl alcohol added as a preservative, supplied in multiple-dose vials. The Hospira label lists trays of 25 vials, not a bulk container. The USP “pharmacy bulk package” designation is limited to injections, and none of the seven bacteriostatic water label entries in DailyMed is described as one (DailyMed search checked 2026-11-01).
Definition and scope
The Hospira (Pfizer) label describes Bacteriostatic Water for Injection as containing 0.9% (9 mg/mL) or 1.1% (11 mg/mL) of benzyl alcohol added as a bacteriostatic preservative. It carries the warning “NOT FOR USE IN NEONATES”, is marked “Rx only”, and is for use only as a diluent or solvent (label text revised 08/2019 and 11/2019). For how this differs from other diluents see bacteriostatic water vs reconstitution solution, bac water vs sodium chloride and what is sterile water.
What “bulk” can mean on a bacteriostatic water label
Cases and trays of multiple-dose vials
The Hospira label lists two packs: NDC 0409-3977-03, a tray of 25 multiple-dose 30 mL plastic Fliptop vials (9 mg/mL benzyl alcohol), and NDC 0409-1093-04, a tray of 25 multiple-dose 20 mL fill in 30 mL glass Fliptop vials (11 mg/mL). The label describes a multiple-dose container from which repeated withdrawals may be made.
The USP “pharmacy bulk package”
USP General Chapter <659> (USP 38-NF 33, an older edition) defines a pharmacy bulk package as a packaging system of a sterile preparation for parenteral use that contains many single doses, intended for a pharmacy admixture program, including filling empty sterile syringes through a sterile transfer device. The designation is limited to Injection, for Injection and Injectable Emulsion, and the package is to be used only in a suitable work area such as a laminar flow hood or an equivalent clean-air compounding area. The chapter also exempts the pharmacy bulk package from the multiple-dose volume limit and from the requirement to contain a substance to prevent the growth of microorganisms.
Multiple-dose packaging in USP
For comparison, the same chapter states that, unless a monograph specifies otherwise, a multiple-dose packaging system contains a volume sufficient to permit withdrawal of no more than 30 mL. A 30 mL multiple-dose vial and a pharmacy bulk package are therefore different packaging classes with different rules.
Comparison: what each reading of “bulk” refers to
| Term | What the sources say | Source |
|---|---|---|
| Tray of 25 multiple-dose vials | NDC 0409-3977-03 (30 mL, 9 mg/mL) and NDC 0409-1093-04 (20 mL in 30 mL glass, 11 mg/mL); repeated withdrawals allowed | Hospira/Pfizer label |
| Multiple-dose packaging (USP) | Volume permits withdrawal of no more than 30 mL unless a monograph states otherwise | USP 38-NF 33 <659> |
| Pharmacy bulk package (USP) | Many single doses; pharmacy admixture; Injection forms only; laminar flow or equivalent area; exempt from the antimicrobial-substance requirement | USP 38-NF 33 <659> |
Documents and details to check before ordering in quantity
This is a checklist of what the sources above make verifiable, not a ranking of suppliers.
- The current FDA-listed label. DailyMed lists the labeler and NDC. A DailyMed search for “bacteriostatic water” (checked 2026-11-01) showed seven label entries: Fujian Genohope Biotech Ltd., Hospira, and repackagers (HealthFirst, ProPharma Distribution, Henry Schein, Medical Purchasing Solutions and US MedSource). None was titled or described as a pharmacy bulk package.
- Rx-only status. The Hospira label is marked “Rx only”.
- Benzyl alcohol strength and the neonate warning. The Hospira label gives 0.9% (9 mg/mL) or 1.1% (11 mg/mL) variants and the statement “NOT FOR USE IN NEONATES”.
- Storage. The Hospira label says store at 20 to 25 C (68 to 77 F).
- Provenance of repackaged stock. The repackager entries in the DailyMed results trace to the source NDC 0409-3977, which links a repackaged label back to the original labeler.
- Distribution records. FDA’s DSCSA page (current as of 10/16/2025) says the law outlines steps to identify and trace certain prescription drugs at the package level, that trading partners must notify FDA within 24 hours after determining a product is illegitimate, and that wholesale distributors and third-party logistics providers report licensure to FDA annually. See also pharmaceutical wholesaler and the FDA registration and listing database.
Bulk bacteriostatic water vs bulk sterile water
The USP pharmacy bulk package is a packaging class defined by use in pharmacy admixture, while the bacteriostatic water on the Hospira label is a multiple-dose vial. See distilled vs sterile water and the bulk medical supplies buying guide for the wider context.
Common misunderstandings
- “Bulk” means a preservative-free pharmacy bulk package. In USP the preservative exemption belongs to the pharmacy bulk package; the Hospira bacteriostatic water label states benzyl alcohol is added.
- A listing’s wording is label evidence. The label and the DailyMed entry for the specific NDC are the documents to compare a listing against.
- A larger quantity changes the product. On the Hospira label, the pack is the same multiple-dose vial in trays of 25.
FAQ
What is bacteriostatic water bulk?
It is a search phrase for bacteriostatic water in quantity. On the Hospira label, the pack is a tray of 25 multiple-dose vials; “bulk” does not appear as a package type for that product.
Is there a pharmacy bulk package of bacteriostatic water?
None of the seven bacteriostatic water label entries in the DailyMed search (checked 2026-11-01) was titled or described as a pharmacy bulk package.
Is bulk bac water sterile?
The Hospira label describes the product as Bacteriostatic Water for Injection, a sterile injection diluent containing benzyl alcohol. The label governs the answer for a given product, so read the label of the specific NDC.
Sources
All sources checked 2026-11-01.
- Hospira/Pfizer, Bacteriostatic Water for Injection label (revised 08/2019 and 11/2019): https://labeling.pfizer.com/ShowLabeling.aspx?id=4666
- DailyMed (NLM), search “bacteriostatic water”: https://dailymed.nlm.nih.gov/dailymed/search.cfm?labeltype=all&query=bacteriostatic+water
- USP 38-NF 33, General Chapter <659> packaging excerpt (public mirror, older edition): https://drugfuture.com/Pharmacopoeia/usp38/data/v38332/usp38nf33s2_c659.html
- FDA, Drug Supply Chain Security Act (DSCSA), current as of 10/16/2025: https://www.fda.gov/drugs/drug-supply-chain-integrity/drug-supply-chain-security-act-dscsa
