Glossary
Beyond-use date (BUD): what it is, and why it is not an expiration date
A beyond-use date is the date, or time and date, after which a compounded preparation must not be used and administration must not begin — that is Ohio’s regulatory definition, in its own words. It is not the same thing as an expiration date. An expiration date belongs to a commercially manufactured product and is determined by stability testing under federal regulation; a beyond-use date is assigned by the compounder on professional judgement, capped by the compendial chapter the pharmacy’s state has adopted. The difference is the kind of evidence behind the date, not its length.
The definition
Ohio’s compounding rule states it in one sentence, and the phrasing is more precise than the shorthand people use:
"Beyond-use date" means either the date or time and date after which a compounded drug preparation must not be used or administration must not begin.
Note the second half. The date does not only bar use; it bars beginning administration, which matters for anything infused or given over a period.
Why it is not an expiration date
The same Ohio rule keeps two words apart that are used interchangeably everywhere else. A product is "a drug in a commercially manufactured pharmaceutical dosage form that has been evaluated for safety and efficacy by the United States food and drug administration." A preparation is "a drug compounded in a licensed pharmacy or other healthcare-related facility."
An expiration date belongs to the first of those, and federal regulation ties it to testing:
To assure that a drug product meets applicable standards of identity, strength, quality, and purity at the time of use, it shall bear an expiration date determined by appropriate stability testing described in § 211.166.
A preparation carries the other kind of date. So a preparation compounded under section 503A carries a beyond-use date assigned under the compendial chapter its state adopted, while something made under cGMP carries an expiration date backed by stability testing on that product. That is a difference in the kind of evidence, and it is not a claim that one runs for more time than the other.
Who assigns it, and what caps it
The compounder assigns it. Arizona’s rule sets out the whole mechanism in a single labelling requirement — judgement, capped by the compendium, extendable only on data:
A beyond-use-date based upon the pharmacist's professional judgment, but not more than the maximum guidelines recommended in the Pharmacy Compounding Practices chapter of the official compendium unless there is published or unpublished stability test data that shows a longer period is appropriate
Which edition of that chapter caps it is a state question, and states run their own transitions. Ohio’s Board is explicit that the newer dating is earned rather than assumed:
IMPORTANT: Licensees are prohibited from utilizing beyond-use dates from the newest versions of USP 797/795 unless they can demonstrate full compliance with those new versions.
That sentence is the reason a prescriber can reasonably ask a supplier which version of <797> it dates to, and whether it can demonstrate full compliance with that version. Where that question sits in a wider diligence sequence is set out in how to vet a compounding pharmacy, and the date itself is a required label element and record entry under several state rules — including for stock supplied to a practice, per how to place an office-use order.