We are often asked, How can I confirm that the Beyond Use Date (BUD) that I assign a particular formulation is appropriate?

The United States Pharmacopeia has provided compounding pharmacists with some general guidelines, spelled out in USP 795, for assigning BUDs. The following are some general rules of thumb when assigning a BUD, regardless of whether it is within or outside of USP guidelines: 

• Consult and apply drug-specific and general stability documentation and literature when available.
• Check the methodology of the analytical lab if you are using potency over time studies to establish your BUDs. Stability indicating is the recommended methodology.
• Document the rationale for an extended BUD by using literature. But compounders must confirm that the references take into account any additional ingredients, quality control testing, the dispensing container and closure system, and storage conditions at your pharmacy.
• Demonstrate that a preparation is stable in a specific proprietary base by seeking information beyond the literature provided by a vendor or other source. Compounders can consult USP Chapter 1161 for additional stability considerations.
• Ensure proper chemical management procedures in your pharmacy. 

It can be easier for pharmacists to eschew the science -- stability indicating assays, advanced testing and the like - and keep all of your their BUDs within the established guidelines of USP.

Yet, as well-educated and highly trained compounding pharmacists, you can tap into your well of chemistry knowledge and determine your BUDs with attention and respect to science and, most importantly, your patients.

-- Ken Speidel, R.Ph, PharmD, FACA, FIACP, Senior Associate