USP 797 Explained: The Sterile Standard Behind Compounded GLP-1s
USP <797> is the sterile compounding standard that governs how a 503A pharmacy makes an injectable like compounded semaglutide or tirzepatide: the cleanroom, the garbing, the testing, and the beyond-use date (BUD) printed on your vial. The current version became official on November 1, 2023, but USP doesn't enforce it. State boards of pharmacy do, which is why the same chapter can carry different weight from state to state.
Key takeaways
- Revised <797> sorts sterile preparations into Categories 1, 2 and 3, and the category sets how long a BUD the pharmacy can assign.
- The longest BUDs depend on passed sterility testing. A long date on your vial implies testing should exist for that lot.
- USP says it "has no role in enforcement." Each state board adopts and inspects against the chapter on its own timeline.
- 503B outsourcing facilities are held to FDA's CGMP rules, a separate and stricter framework.
What USP <797> is, and what it isn't
The United States Pharmacopeia is a nonprofit standards body. Its General Chapter <797>, "Pharmaceutical Compounding: Sterile Preparations," sets minimum practices for preparing compounded sterile preparations (CSPs). The revised chapter was published November 1, 2022 and became official November 1, 2023 (Drug Topics).
USP is explicit that it is not a regulator. Its own FAQ states that "USP has no role in enforcement" and that regulators such as state boards may set different official dates (USP <797> FAQ). A pharmacy's legal duty comes from its state's pharmacy rules, which usually incorporate <797> by reference.
For a compounded GLP-1, <797> matters because the drug is injected. A contaminated injection bypasses the body's outer defenses. The chapter exists to keep microbes and endotoxins out of the vial and to cap how long a vial can be considered safe to use.
The three categories
The 2023 revision dropped the old low, medium and high risk levels in favor of categories tied to the compounding environment and quality controls (Drug Topics).
| Category | Where it's made | BUD range | Sterility testing |
|---|---|---|---|
| Category 1 | ISO Class 5 hood in an unclassified segregated area | Up to 12 hours room temp, 24 hours refrigerated | Not required |
| Category 2 | ISO Class 5 hood inside an ISO Class 7 buffer room with an ISO Class 8 or better anteroom | 1 to 90 days, depending on method and testing | Required only when the assigned BUD calls for it |
| Category 3 | Category 2 environment plus added quality controls | 60 to 180 days | Always required |
Source: Wolters Kluwer summary of revised USP <797>; USP <797> FAQ.
Category 3 is a voluntary step up. USP describes it as a facility that "meets additional quality assurance requirements," with stricter rules on personnel qualification, garb, sporicidal disinfection, environmental monitoring frequency, and stability determination (USP <797> FAQ).
Beyond-use dates: the number on your vial
The BUD is the date after which a compounded preparation should not be used. It is not the same as a manufacturer's expiration date, which is backed by formal stability studies on an approved product. Under <797>, the BUD a pharmacy can assign depends on how the product was made, whether its starting ingredients were sterile, whether it passed sterility testing, and how it's stored.
| How it was prepared | Testing | Room temp | Refrigerated | Frozen |
|---|---|---|---|---|
| Cat. 2, aseptic, nonsterile starting components | No sterility test | 1 day | 4 days | 45 days |
| Cat. 2, aseptic, sterile starting components only | No sterility test | 4 days | 10 days | 45 days |
| Cat. 2, aseptic | Sterility test passed | 30 days | 45 days | 60 days |
| Cat. 2, terminally sterilized | Sterility test passed | 45 days | 60 days | 90 days |
| Cat. 3, aseptic | Sterility and all applicable tests passed | 60 days | 90 days | 120 days |
| Cat. 3, terminally sterilized | Sterility and all applicable tests passed | 90 days | 120 days | 180 days |
Source: Wolters Kluwer, summary of revised USP <797> BUD limits. These are maximums; the official chapter text controls.
Read that table against your own vial. A compounded GLP-1 made from nonsterile API powder that was never sterility tested can carry a refrigerated BUD of no more than 4 days under Category 2. A refrigerated BUD of several weeks implies the pharmacy relied on a passed sterility test, and a refrigerated BUD beyond 45 days implies Category 3 status for aseptically prepared product.
These are ceilings, not guarantees. A pharmacy must also consider chemical stability, and a peptide can degrade well before its sterility-based BUD. Our article on compounded semaglutide stability chemistry covers that side.
Rather skip the BUD math?
FDA-approved GLP-1 pens carry manufacturer expiration dates backed by stability studies.
Paid links. We may earn a commission; it never changes what we write. See all options. Compounded medications are not FDA-approved.
Testing requirements that apply to GLP-1 injections
Two lab tests do most of the work for injectables: sterility (does anything grow?) and bacterial endotoxins (are there fever-causing bacterial fragments?). Revised <797> ties both to category and starting materials:
- Endotoxin testing: Category 2 injectables compounded from nonsterile components must be tested for endotoxins when they carry a BUD that requires sterility testing, and testing is recommended even when it doesn't. Category 3 injectables from nonsterile components must be tested (USP <797> FAQ).
- Sterility testing sample size: For batches of 1 to 39 units, the pharmacy tests 10% of units, rounded up, and batches requiring sterility testing are limited to 250 final dosage units (USP <797> FAQ).
- Multiple-dose vials: If your compounded GLP-1 comes in a vial you puncture for several doses, this one matters. USP's FAQ says aqueous multiple-dose CSPs must pass antimicrobial effectiveness testing under USP <51> (USP <797> FAQ), which checks that the preservative system actually suppresses microbes introduced with each needle stick.
What <797> does not require is routine potency testing of every batch. Strength accuracy depends on the pharmacy's own procedures, which is why our certificate of analysis guide treats potency as a separate question to ask.
The people and the room
A large share of <797> is about process rather than product. Compounders must demonstrate competency through observed hand hygiene and garbing, gloved fingertip sampling, and media-fill tests (simulated compounding with growth media). For Category 1 and 2 compounders that happens every 6 months; for Category 3, every 3 months (Drug Topics).
The environment is monitored, too. Viable air sampling is required every 6 months for Categories 1 and 2 and monthly for Category 3; surface sampling is monthly for Categories 1 and 2 and weekly for Category 3 (Drug Topics). These records are what a board inspector reviews, and they're what a patient never sees.
How state boards enforce <797>
Because USP has no enforcement role, each state decides when and how the revised chapter becomes binding. Utah's compounding advisory committee, for example, told licensees in 2023 that the revised chapters "will not be enforced in Utah until they are adopted into Utah Pharmacy regulation," and that prior versions remained enforceable in the meantime (Utah APCEC).
In practice, enforcement runs through licensure and inspection. A board can inspect a pharmacy's cleanroom certification, environmental monitoring logs, training records, and BUD assignments, then discipline the license if they fall short. Boards have also issued GLP-1-specific statements layered on top of <797>. Kansas, for instance, prohibits salt forms, non-pharmaceutical-grade API, and API from non-FDA-registered establishments, and bars pharmacists from dispensing GLP-1s compounded in a non-compliant manner (Kansas Board of Pharmacy, updated April 2026).
That patchwork is why a pharmacy's license status and disciplinary history, which you can look up on its state board's site, is one of the most useful signals a patient has.
503A vs. 503B: which rulebook applies
<797> is a pharmacy-practice standard, and it's the main sterility rulebook for 503A compounding pharmacies, which FDA notes are exempt from CGMP requirements when they meet section 503A's conditions (FDA Import Alert 66-80).
Outsourcing facilities registered under section 503B are different. FDA states they "are subject to CGMP requirements," must report adverse events to FDA, and are inspected on a risk-based schedule (FDA). USP's own FAQ notes that <797>'s 250-unit batch limit and related parameters "are not intended for outsourcing facilities" (USP <797> FAQ). Our 503A vs. 503B explainer covers the broader legal split.
One more piece of context: as of April 2026, FDA says tirzepatide and semaglutide do not appear on the 503B bulks list or on FDA's drug shortage list, and its shortage-era enforcement discretion periods have ended (FDA). Sterile technique under <797> is necessary for a lawful compounded GLP-1, but it is not sufficient. The prescription and ingredient also have to meet federal compounding conditions.
What you can check as a patient
- Read the BUD and storage instructions. Compare them with the table above. A long refrigerated BUD should line up with sterility testing.
- Ask the category. "Is this a Category 2 or Category 3 preparation, and was my lot sterility and endotoxin tested?"
- Ask about the vial type. If it's a multiple-dose vial, ask whether the formulation passed antimicrobial effectiveness testing.
- Look up the license. Check the dispensing pharmacy's status and any discipline with its state board, or the FDA outsourcing facility list for a 503B.
- Talk to your prescriber if answers are vague or the BUD doesn't add up.
Comparing your options?
See what current providers charge for FDA-approved GLP-1 medications.
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Frequently asked questions
When did the revised USP <797> take effect?
The revised chapter was published November 1, 2022 and became official November 1, 2023. Each state board decides when it enforces the revision, so timing can differ by state.
Who enforces USP <797>?
Not USP, which says it has no role in enforcement. State boards of pharmacy adopt the chapter into their rules and enforce it through licensing and inspections.
What does the beyond-use date on my compounded GLP-1 vial mean?
It is the date after which the preparation should not be used. Under USP <797>, the maximum BUD depends on the preparation's category, whether starting ingredients were sterile, whether it passed sterility testing, and storage temperature.
Does USP <797> apply to 503B outsourcing facilities?
503B outsourcing facilities are subject to FDA's CGMP requirements, a separate framework. USP notes some <797> parameters, such as its 250-unit batch limit, are not intended for outsourcing facilities.
Sources
- Drug Topics, USP <797> Updated Guidelines
- USP, General Chapter <797> FAQs (updated December 11, 2023)
- Wolters Kluwer, USP Beyond-Use Dates (BUDs)
- Utah Advisory Pharmacy Compounding Education Committee, USP Update Letter (2023)
- Kansas Board of Pharmacy, Statement on Compounded GLP-1 and GIP Receptor Agonists (updated April 22, 2026)
- FDA, Questions and Answers: Outsourcing Facility Registration
- FDA, Import Alert 66-80
- FDA, FDA Clarifies Policies for Compounders as National GLP-1 Supply Begins to Stabilize
Medical disclaimer: This article is general information, not medical advice, and does not replace a licensed clinician who knows your history. Approvals, labels, coverage and prices change; check the linked sources and talk with your prescriber or pharmacist before making decisions about any medication.