Beyond-use dates (BUD), explained — the chart, the rules, and your GLP-1 vial
Updated 2026-08-10 — rebuilt as the reference page for BUD questions: the abbreviation, the USP chart, the calculation rules, and what it all means for a GLP-1 vial.
BUD stands for beyond-use date — the date after which a compounded preparation should not be used, assigned by the pharmacy when it prepares your medication. On a prescription label, "BUD" or "beyond-use date" is that deadline. It is not the same as an expiration date: expiration dates come from manufacturers after formal stability testing of mass-produced drugs; BUDs are conservative limits for pharmacy-made preparations, set under USP standards — which is why a compounded GLP-1 vial may carry a use-by window of weeks while a factory pen shows a shelf life of years.
The BUD chart: USP defaults in plain language
| Preparation type | Typical default BUD | Notes |
|---|---|---|
| Non-sterile, water-containing, preserved (USP <795>) | up to 35 days | Refrigeration often required |
| Non-sterile, water-containing, no preservative (USP <795>) | up to 14 days | Refrigerated |
| Non-sterile, non-aqueous (USP <795>) | up to 90 days | Oils, some suspensions |
| Non-sterile solids — capsules, tablets (USP <795>) | up to 180 days | Longest non-sterile category |
| Sterile, Category 1 (USP <797>) | hours: ≤12 room temp / ≤24 refrigerated | Prepared outside full cleanroom conditions |
| Sterile, Category 2 (USP <797>) | days to weeks | Cleanroom-prepared; length depends on sterility testing and storage |
| Sterile, Category 3 (USP <797>) | extended, testing-supported | Requires additional stability/sterility work |
Injectable compounded GLP-1s are sterile preparations, so their BUDs live in the <797> framework — commonly landing in the multi-week range for refrigerated vials from well-run pharmacies. The exact number on your label wins over any chart, including this one.
How a BUD is actually calculated
The pharmacy starts from the USP category defaults above, then shortens as needed for the specific formulation's stability data, the sterility assurance of its process, preservative status, container, and storage conditions. That's why the honest answer to "how to calculate beyond use date" is: you don't — the compounder does, and your job is to read it, refrigerate as directed, and never use past it. The related question we get — "does GLP-1 really expire after 28 days?" — has a precise answer: the drug molecule doesn't vanish at day 28, but past the BUD the pharmacy no longer stands behind sterility and potency, and with an injectable, sterility is the whole game. Using past the BUD is a risk transfer from the pharmacy's quality system to you.
Why BUDs decide how you should buy
Short BUDs interact directly with plan structure: a 3-month prepaid supply shipped in one box can out-run its own beyond-use dates — the trap detailed in BUDs on multi-month plans. Confirm shipment cadence separately from plan length, check the BUD on every arrival (part of the four-label-reads routine), and treat a pharmacy that ships product with most of its BUD already consumed as a red flag worth a call. Full storage-and-handling context: vials & concentrations and the summer cold-chain checklist.
Frequently asked questions
What does BUD stand for in pharmacy?
Beyond-use date — the pharmacy-assigned date after which a compounded preparation should not be used. On a prescription or vial label, BUD marks that deadline.
Are beyond-use date and expiration date the same thing?
No — they are not interchangeable. Expiration dates come from manufacturer stability testing of mass-produced drugs; BUDs are conservative pharmacy-assigned limits for compounded preparations under USP standards, usually much shorter.
What is the beyond-use date chart for compounding?
USP <795> non-sterile defaults: up to 35 days (aqueous, preserved), 14 days (aqueous, unpreserved), 90 days (non-aqueous), 180 days (solids). Sterile preparations follow USP <797> Categories 1–3, from hours to testing-supported extended dating. The pharmacy's assigned BUD can be shorter than any default.
How is a beyond-use date calculated?
The compounding pharmacy assigns it, starting from USP category defaults and shortening for formulation stability, sterility assurance, preservatives, container, and storage. Patients don't calculate BUDs — they follow the label.
Does compounded GLP-1 really expire after 28 days?
The BUD isn't a potency cliff — it's the end of the pharmacy's sterility and potency assurance. For an injectable, using past the BUD means assuming that risk yourself; the label date governs.