When assigning a beyond-use date, pharmacists should consult and apply drug-specific and general stability documentation and literature where available, and they should consider the nature of drug and its degradation mechanism, the container in which it is packaged, the expected storage conditions, and the intended duration of therapy (see ).
It is acceptable to declare a "freeze by" date in addition to, and that is the same as, the "best before" date in a clear statement indicating that the product can be frozen if not consumed by the "best before" date.
Beyond-use dates for compounded preparations are usually assigned based on professional experience, which should include careful interpretation of appropriate information sources for the same or similar formulations (see ) for manufactured products.
The majority of CSPs are aqueous solutions in which hydrolysis of dissolved ingredients is the most common chemical degradation reaction.
The extent of hydrolysis and other heat-catalyzed degradation reactions at any particular time point in the life of a CSP represents the thermodynamic sum of exposure temperatures and durations.
Beyond-use dates for CSPs that are prepared strictly in accordance with manufacturers' product labeling must be those specified in that labeling, or from appropriate literature sources or direct testing.
Beyond-use dates for CSPs that lack justification from either appropriate literature sources or by direct testing evidence must be assigned as described in the section In addition, the pharmacist may refer to applicable publications to obtain relevant stability, compatibility, and degradation information regarding the drug or its congeners.
Such lifetime stability exposure is represented in the mean kinetic temperature calculation (see Personnel who prepare, dispense, and administer CSPs must store them strictly in accordance with the conditions stated on the label of ingredient products and finished CSPs.
When CSPs are known to have been exposed to temperatures warmer than the warmest labeled limit, but not exceeding 40 (see When CSPs deviate from conditions in the approved labeling of manufactured products contained in CSPs, compounding personnel may consult the manufacturer of particular products for advice on assigning beyond-use dates based on chemical and physical stability parameters.
It must be ascertained that CSPs will not be exposed to warm temperatures (see It should be recognized that the truly valid evidence of stability for predicting beyond-use dating can be obtained only through product-specific experimental studies.
Semi-quantitative procedures, such as thin-layer chromatography (TLC), may be acceptable for many CSPs.
However, in the case of formulated liquid diets, infant formula, and foods represented as containing infant formula, this information can be shown on any panel including the bottom panel provided there is a clear indication of the location of the date elsewhere on the label [B.01.005(4), , lot codes) and therefore are not prohibited on food products, provided they are not misleading and the label meets appropriate requirements.