Beyond-use date (revision 4)

A beyond-use date (BUD) is the date, or date and time, after which a compounded preparation or an opened container is not to be used. It is assigned by the person who prepares or opens the preparation, using compendial default tables or, where available, testing specific to the preparation. It is distinct from an expiration date, which is assigned by a manufacturer on the basis of a formal stability programme conducted on the finished product in its final container.^[1][2]

The distinction is one of evidence rather than of vocabulary. An expiration date rests on long-term, intermediate and accelerated stability studies conducted under the conditions specified in ICH Q1A(R2), analysed statistically, and submitted to a regulator; it is a claim about the specific product in the specific container. A beyond-use date generally rests on a table of conservative defaults chosen to be safe across a wide range of preparations, and it is a claim about a class of preparations rather than about the one in hand. The two are therefore not comparable quantities, and a short beyond-use date does not imply a preparation degrades quickly.^[3][1]