Beyond-Use Dating & Labeling in Compounded Sterile Products (CSPs)

Key Takeaway

Label BUDs to direct when to start the infusion. Prefer Must be hung by [date/time] or Start infusion by [date/time]. If the infusion is hung on time, it may run to completion even if the BUD clock passes during administration, unless product-specific instructions state otherwise.

What Is a Beyond-Use Date (BUD)?

The Beyond-Use Date (BUD) is the assigned date/time after which a compounded sterile product (CSP) is no longer suitable for use, determined per USP <797> using microbial risk, sterility assurance, chemical/physical stability, container/closure, and storage conditions.

USP <797> intent: the BUD indicates the latest time by which a CSP must be initiated (hung/started). Once administration begins within the BUD, the infusion may continue to completion, provided other stability and “in-use” limits are met.

Common Misinterpretation in Practice

Incorrect: “BUD = finish line.”
Consequences: waste, delays, confusion.
Correct: “BUD = last acceptable start time.”

Timeline Example

At a Glance

✅ Hang infusion if current time ≤ BUD.
✅ Infusion may finish after BUD if started on time.
⛔ Do NOT hang if current time > BUD — contact pharmacy.
⛔ Do NOT discard a bag already infusing on time unless directed.

Recommended Label Verbiage

Use (preferred)

Must be hung by [date/time]
Start infusion by [date/time]
Begin administration by [date/time]

Avoid

Do not use after — often misread as “finish by”.
Infuse completely by / Start and complete by.
Do not hang after — similar to "Do not use after".

Important: Follow any product-specific in-use or stability limits when stricter than general BUD principles.

BUD vs. Manufacturer Expiration Date

Attribute	Beyond-Use Date (BUD)	Expiration Date
Who assigns?	Compounding pharmacy per USP <797> + evidence.	Manufacturer under FDA-regulated stability programs.
What it governs	Latest acceptable start time for administration.	Quality/potency in unopened original container.
Key determinants	Risk category, aseptic controls, storage temp, container, stability, in-use limits.	ICH stability studies and labeled storage.
After it passes	Do not start after BUD. If started on time, may run to completion unless stricter limits apply.	Do not use unopened product past expiration.
Typical time scale	Hours to days (sometimes longer with data/controls).	Months to years.
Communication	Action phrasing (e.g., `Must be hung by`).	Informational dating on commercial label.

Implementation Tips for Health-System Practice

Standardize the phrase: e.g., Must be hung by [date/time].
Surface time clearly: 24-hour time with local date to reduce AM/PM errors.
Pair storage cues: e.g., Refrigerate. Protect from light.
Respect stricter limits: e.g., “discard 6 hours after spike.”
Educate interprofessionally: reinforce “BUD = last start time.”

Sample Label Snippets

General CSP

Medication: Cefazolin 2 g in NS 100 mL (CSP)
BUD / Start-by: Must be hung by 9-22-2025 14:00
Storage: Refrigerate. Allow to reach room temp before use.
Note: If hung by the Start-by time, infusion may run to completion.

With In-Use Limit

Medication: Vancomycin 1 g in D5W 250 mL (CSP)
BUD / Start-by: Start infusion by 9-22-2025 12:00
In-Use: Discard 6 hours after bag is spiked.
Note: If hung on time, infusion may run to completion within in-use window.

Summary

Treat the BUD as a start-by instruction (Must be hung by [date/time]). If started on time, the infusion may continue to completion even if the BUD passes during administration, unless product-specific limits say otherwise.