The Bacteriostatic water is sterile water for injection that contains benzyl alcohol as a preservative, used to dilute or dissolve drugs for injection. Reconstitution is the step of dissolving a powdered medication in a liquid such as bacteriostatic water before injection. BrightSide's compounded NAD+ and glutathione injections arrive as a liquid and need no reconstitution.
How do bacteriostatic water and reconstitution apply to compounded GLP-1 treatment?
Reconstitution applies only when a medication is supplied as a powder. The FDA-approved GLP-1 injections are not. The Wegovy label describes a clear, colorless solution, and the Zepbound label describes a clear, colorless to slightly yellow solution, so neither is mixed before use. Compounded medications vary by pharmacy. Some arrive as a liquid that is ready to draw, and some medications are supplied as a freeze-dried powder that has to be mixed first. United States Pharmacopeia chapter 797 counts reconstituting as part of sterile compounding, so when a pharmacy does the mixing, it works under that chapter. If a prescription ever reaches you as a powder, the pharmacy label and instructions say which liquid to use and how much. Ask before you mix anything. BrightSide's NAD+ injection and glutathione injection both come as a liquid in a vial.
What is in bacteriostatic water?
Bacteriostatic water is water for injection with a small amount of benzyl alcohol added. The label for Hospira's Bacteriostatic Water for Injection, USP, describes a sterile, nonpyrogenic preparation that contains 0.9 percent or 1.1 percent benzyl alcohol as a bacteriostatic preservative. It is supplied in a multiple-dose container, from which repeated withdrawals can be made to dilute or dissolve drugs for injection. The label says it is indicated only for diluting or dissolving drugs for intravenous, intramuscular or subcutaneous injection, according to the instructions of the manufacturer of the drug. It carries one prominent warning, that it is not for use in neonates, because of the potential toxicity of benzyl alcohol in that group. Where water is needed to prepare medications for neonates, the label says only preservative-free Sterile Water for Injection should be used. The label lists storage at 68 to 77 degrees Fahrenheit.
What does reconstitution look like on an FDA-approved label?
An FDA-approved label for a powdered drug gives exact mixing steps, and those steps belong to that product alone. For a powdered medication you mix with bacteriostatic water before injecting, the label names the liquid and how much of it to add, says how to mix the vial and what the mixed solution should look like, and says how long the solution and the bacteriostatic water can be kept. The Hospira label makes the general point: consult the drug manufacturer's instructions for the choice of liquid and the volume. For a compounded prescription, those instructions come from the pharmacy. Our pharmacy network page covers how we choose pharmacies.
| Item | What the label says |
|---|---|
| Contents | Sterile, nonpyrogenic water for injection with benzyl alcohol |
| Preservative | Benzyl alcohol, 0.9 percent (9 mg/mL) or 1.1 percent (11 mg/mL) |
| Container | Multiple-dose vial, 30 mL |
| Use | Only for diluting or dissolving drugs for intravenous, intramuscular or subcutaneous injection |
| Warning | Not for use in neonates |
| Storage | 20 to 25 degrees Celsius (68 to 77 degrees Fahrenheit) |
Common questions
Is bacteriostatic water the same as sterile water?
No. Bacteriostatic water contains benzyl alcohol as a preservative and comes in a multiple-dose container. Sterile Water for Injection is preservative-free. The Hospira label says that where water is required to prepare or dilute medications for neonates, only preservative-free Sterile Water for Injection should be used. The label for the drug being mixed says which liquid to use.
Do you have to reconstitute a BrightSide prescription?
Not for NAD+ injection or glutathione injection, which come as a liquid in a vial. For any prescription, your pharmacy label and your provider's directions come first. If a vial arrives looking different from what you expected, email hello@jointhebrightside.com before you use it, and a person answers.
Related terms
- Lyophilized vial: a vial of freeze-dried medication that is reconstituted before use.
- Subcutaneous injection: how the mixed medication is given.
- Beyond use date (BUD): the date after which a compounded vial must not be used.
- 503A compounding pharmacy: the pharmacy that makes a compounded vial.
Sources
- Bacteriostatic Water for Injection, USP, label, Hospira, revised 8/2019, on DailyMed: https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=87d6e9dc-fe3b-4593-ac9a-d7493d1959c7
- USP, General Chapter 797 frequently asked questions, updated December 11, 2023: https://pages.usp.org/rs/711-SXF-172/images/USP_HQS_797_FAQs_December2023_V6__002.pdf?version=0
- Zepbound (tirzepatide) prescribing information, Eli Lilly, revised 8/2026, on DailyMed: https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=487cd7e7-434c-4925-99fa-aa80b1cc776b
Compounded medications are not FDA approved. They are prescribed by a licensed clinician and filled by a licensed 503A pharmacy.
