Is this vial OK?

How this tool works · sources read November 3, 2026 · Grey Peptides Editorial Board

What the checker does

You answer what you can about one vial: what the powder looked like before you mixed it, what the liquid looks like now, the water you used, how many days ago you mixed it, where it is kept, whether it has frozen or been left warm, and whether the glass, cap or seal is damaged. Every question is optional. Each answer that matches a rule gets its own result, with the label sentence, guidance or study the rule rests on, and the strongest result is shown at the top. Nothing you enter is stored or sent: the answers live in the page and are gone when you close it.

What the three results mean

Discard means a source we read says not to use, or to throw away, a vial in that state, or the finding is a sign of contamination (anything visible that should not be there, a broken seal, a water that is not sterile). The checker is conservative on purpose: any particle, cloudiness, colour, foam that will not settle, undissolved powder or later crystals is Discard, because approved peptide labels set that bar for their own products.^{1 2}

Unknown — ask a pharmacist means the sources do not settle it. Most often that is because labels give their own product a rule, the rules differ from product to product, and a research peptide has no label saying which one applies.

Likely fine means the answer matches what labels describe as normal, such as a clear, colourless solution.^{3 4} It is never a statement that a vial is safe. Some contamination cannot be seen, and a vial can hold more, less or none of what its label says;⁵ our page on contamination and reactions sets out what looking cannot catch.

Every rule and its source

The table is the checker's own rule list; the page and this table are written from the same data, and the site's build fails if a label sentence the checker quotes is no longer in that label's current version.

How the days-since-mixing rule works

The rule depends on the water. With bacteriostatic water or bacteriostatic saline, the water's label says a drug dissolved in it is used promptly and that reconstituted solutions are not stored unless the drug's own maker directs it.¹⁵ CDC, quoting USP General Chapter 797, says a manufacturer's multiple-dose vial, once opened, is dated and discarded within 28 days unless the manufacturer states another date, and the Joint Commission says the same.^{18 22} So day 0 is Likely fine, more than 28 days is Discard, and anything between is Unknown: 28 days is a sterility limit for a maker's vial, not a time any peptide you mix was shown to keep, and makers' own periods range from 3 days for metreleptin to 60 days refrigerated for hCG.^{6 7}

With sterile water or plain saline, which have no preservative and come in single-dose containers, a dose given the day you mix is Likely fine, and a day or more later is Discard: the saline label says to discard the unused portion, and CDC says leftover single-dose contents are not stored for later.^{20 18} With tap, bottled, distilled or boiled water the result is Discard whatever the day: none is sterile water for injection.²¹ Our bacteriostatic water guide covers each water's label in full.

Freezing, warmth and storage

A mixed solution that has frozen is Discard: labels say a reconstituted product frozen even by accident is thrown away, and not to use one that has been frozen.^{6 24} The refrigerator (2 to 8 °C) is Likely fine because that is where approved freeze-dried peptides that may be kept after mixing are kept, with one exception named on the result: EGRIFTA SV's label says not to refrigerate its mixed solution and to use it at once.³ Room temperature, hours out of the fridge, and heat are Unknown: heat and light produced ten impurities in liraglutide that were found only by laboratory mass spectrometry,²³ and preservatives including benzyl alcohol increased a protein's aggregation at 50 °C,¹⁶ though benzyl alcohol did not aggregate one acylated peptide that was tested.¹⁷ None of these gives a limit for a research peptide. Our guide to storing peptides has the refrigerator detail.

What it cannot tell you

The checker can only work with what you can see and remember. It cannot see endotoxin or bacteria in a clear solution, cannot measure how much peptide is left, and cannot tell a vial that never held the right compound from one that did. A collapsed powder cake shows that drying or storage went wrong, and in one study some collapsed protein cakes broke down in storage while others did not;⁸ that is why it is Unknown rather than Likely fine. Where your product has an approved label, that label is the source, not this page. If you have injected from a vial and have a spreading redness, fever or trouble breathing, get medical care; our page on syringe reuse and sterility covers needle handling, and FDA's guidance lists what visible particles in an injection can do.⁹

Sources

1. Theratechnologies Inc. EGRIFTA WR (tesamorelin for injection), prescribing information: "Do not use if solid particles appear or if the solution is cloudy or colored." DailyMed set 839334d3, version 2, effective July 29, 2026; read from the cached label November 3, 2026. DailyMed
2. Takeda GATTEX (teduglutide) for injection, prescribing information: "Do not shake or freeze the reconstituted solution."; "If the product remains undissolved after the second attempt, do not use."; "If there is any discoloration or particulates, discard the solution."; "Reconstituted GATTEX is a sterile, clear, colorless to light straw-colored solution, which should be free from particulates." DailyMed set 66b69c1e, version 20, effective September 5, 2025; read from the cached label November 3, 2026. DailyMed
3. Theratechnologies Inc. EGRIFTA SV (tesamorelin for injection), prescribing information: "Do not freeze or refrigerate the reconstituted solution."; "If not used immediately, discard the reconstituted solution."; "Use only if the solution is clear, colorless and without particulate matter." DailyMed set 3d783378, version 9, effective July 29, 2026; read from the cached label November 3, 2026. DailyMed
4. Novo Nordisk WEGOVY (semaglutide) injection, prescribing information: "Only use if the solution is clear, colorless, and contains no particles." DailyMed set ee06186f, version 19, effective June 18, 2026; read from the cached label November 3, 2026. DailyMed
5. Reichel, C. et al. (2019). Detection of black market follistatin 344. Drug Testing and Analysis, 11(11-12), 1675-1697. PMID: 31758732
6. Chiesi USA, Inc. MYALEPT (metreleptin) for injection, prescribing information: "Do not use if the white lyophilized cake is discolored."; "If the reconstituted product is inadvertently frozen, it should be thrown away."; "The cake of lyophilized powder should be intact and white in color."; "When properly mixed, the MYALEPT reconstituted solution should be clear and free of clumps or dry powder, bubbles or foam."; "when MYALEPT is reconstituted with BWFI, the vial can be used for multiple doses within 3 days when stored in the refrigerator at 36°F to 46°F (2°C to 8°C) and protected from light." DailyMed set d3b50bbd, version 18, effective March 25, 2024; read from the cached label November 3, 2026. DailyMed
7. Organon PREGNYL (chorionic gonadotropin for injection), prescribing information: "IF NEEDED, THE RECONSTITUTED SOLUTION IS STABLE FOR 60 DAYS WHEN REFRIGERATED."; "If there is a discoloration or particulates, do not use."; "PREGNYL is a white, dry powder / cake." DailyMed set 1e94155f, version 11, effective December 2, 2025; read from the cached label November 3, 2026. DailyMed
8. Ohori, R. et al. (2018). Effect of temperature ramp rate during the primary drying process on the properties of amorphous-based lyophilized cake, Part 2: Successful lyophilization by adopting a fast ramp rate during primary drying in protein formulations. European Journal of Pharmaceutics and Biopharmaceutics, 130, 83-95. PMID: 29913271
9. U.S. Food and Drug Administration. Inspection of Injectable Products for Visible Particulates: draft guidance for industry, December 2021 (content current as of December 17, 2021; draft, not for implementation): the kinds of visible particles found in injectables (including glass, fibre, rubber, mould and precipitate) and the harms they can cause. Read October 28, 2026. FDA
10. Eli Lilly and Company MOUNJARO (tirzepatide) injection, prescribing information: "It should appear clear and colorless to slightly yellow." DailyMed set d2d7da5d, version 40, effective August 27, 2026; read from the cached label November 3, 2026. DailyMed
11. Amphastar Pharmaceuticals, Inc. Glucagon for injection emergency kit, prescribing information: "If the resulting solution is cloudy or contains particulate matter do not use." DailyMed set 8cc40354, version 4, effective August 11, 2026; read from the cached label November 3, 2026. DailyMed
12. Onyx Pharmaceuticals, Inc. KYPROLIS (carfilzomib) for injection, prescribing information: "If foaming occurs, allow the solution to settle in the vial until foaming subsides (approximately 5 minutes) and the solution is clear." DailyMed set ea66eb30, version 59, effective June 18, 2025; read from the cached label November 3, 2026. DailyMed
13. Takeda MIMRYLO (rusfertide) for injection, prescribing information: "Visually inspect that the reconstituted solution is clear with very little foam, colorless, and free from visible particles." DailyMed set 101aff01, version 2, effective August 28, 2026; read from the cached label November 3, 2026. DailyMed
14. Pharmacia & Upjohn (Pfizer) SOMAVERT (pegvisomant) for injection, prescribing information: "If foaming of the reconstituted SOMAVERT solution is seen, the solution is likely damaged and therefore inappropriate to inject." DailyMed set 3cbb485b, version 13, effective December 18, 2025; read from the cached label November 3, 2026. DailyMed
15. Hospira, Inc. Bacteriostatic Water for Injection, USP, prescribing information: "Do not store reconstituted solutions of drugs for injection unless otherwise directed by the manufacturer of the solute."; "Do not use unless the solution is clear and seal intact."; "Inspect reconstituted (diluted or dissolved) drugs for clarity (if soluble) and freedom from unexpected precipitation or discoloration prior to administration."; "When diluting or dissolving drugs, mix thoroughly and use promptly." DailyMed set 87d6e9dc, version 20, effective May 22, 2026; read from the cached label November 3, 2026. DailyMed
16. Arora, J. et al. (2017). Correlating the Effects of Antimicrobial Preservatives on Conformational Stability, Aggregation Propensity, and Backbone Flexibility of an IgG1 mAb. Journal of Pharmaceutical Sciences, 106(6), 1508-1518. PMID: 28212986
17. Li, M. et al. (2022). Molecular Mechanism of Antimicrobial Excipient-Induced Aggregation in Parenteral Formulations of Peptide Therapeutics. Molecular Pharmaceutics, 19(9), 3267-3278. PMID: 35917158
18. Centers for Disease Control and Prevention. Preventing Unsafe Injection Practices (Injection Safety: clinical safety), last reviewed March 26, 2024: quoting United States Pharmacopeia General Chapter 797, which defines reconstituting a drug as sterile compounding; once a manufacturer's multi-dose vial is opened (needle-punctured) it should be dated and discarded within 28 days unless the manufacturer states another date for that opened vial (a sterility limit); do not combine or store leftover contents of single-dose vials for later use; the preservative in a multi-dose vial does not act on viruses nor give complete protection against bacterial contamination. Re-read November 3, 2026. CDC
19. Medefil, Inc. Sterile Water for Injection, USP, prescribing information: "Do not use unless the solution is clear and seal intact." DailyMed set 99e99a50, version 5, effective January 8, 2025; read from the cached label November 3, 2026. DailyMed
20. Hospira, Inc. 0.9% Sodium Chloride Injection, USP (single-dose vials), prescribing information: "Do not reuse single-dose containers, discard unused portion." DailyMed set 8eb172da, version 26, effective November 6, 2024; read from the cached label November 3, 2026. DailyMed
21. Miko, S. et al. (2023). (Mis)perception and Use of Unsterile Water in Home Medical Devices, PN View 360+ Survey, United States, August 2021. Emerging Infectious Diseases, 29(2), 397-401. PMID: 36692441
22. The Joint Commission. Multi-dose Vials - Managing Multi-dose Vials of Injectable Medication (standards FAQ, home care, 000001529): an opened or accessed (needle-punctured) multi-dose vial should be dated and discarded within 28 days unless the manufacturer specifies a different date for that opened vial (a sterility limit for a manufacturer's multiple-dose vial). Read October 27, 2026. Joint Commission
23. Badgujar, D. et al. (2025). Assessment of Thermal and Photolytic Stress Effects on the Stability of Primary Structure of Synthetic Liraglutide Using LC-HRMS/MS. Journal of Peptide Science, 31(9), e70050. PMID: 40814845
24. Amgen Inc. EPOGEN (epoetin alfa) injection, prescribing information: "Do not use Epogen that has been shaken or frozen." DailyMed set 1f2d0b28, version 137, effective June 23, 2026; read from the cached label November 3, 2026. DailyMed
25. B. Braun Medical Inc. Sterile Water for Irrigation, USP (quoted for its container and seal precaution only), prescribing information: "Use only if solution is clear and container and seal are intact." DailyMed set f4284eb6, version 9, effective September 18, 2026; read from the cached label November 3, 2026. DailyMed

This explainer describes how the tool works and what its numbers rest on. It is not medical advice and does not recommend any dose or product.