When an official monograph isn't present, a systematic approach to assigning the date can be as follows: Step 1.Beyond use dates should be in accordance with the manufacturer's approved labeling.
Beyond use dates are different from expiration dates.
Expiration dates are required on commercially manufactured products and are determined after extensive study of the product's stability.
Until now, such sterility testing of compounded batches has been very inconvenient, complex, and cost-prohibitive.
The Exten DATE™ Sterility Testing system provides a convenient, simple, and inexpensive answer.
Direct extrapolation of the information to the specific compounded formulation requires that the scientific study data utilize the same drug source, the same drug concentration, and the same compounding procedures, stores the formulation in the same container, and has subjected the formulation to the same anticipated environmental variables.
A growing number of reference sources contain stability information, and the pharmacist should have ready access to this material. Many times the published references do not evaluate exactly the same formulation, or the study did not examine the stability for a long enough period of time.
Recent concern about the quality of CSPs acquired from commercial compounding facilities by the hospital and clinical pharmacy has led to an increased interest in performing batch compounding in-house.
Even when the chemical stability of the drug is sufficient to allow longer expiration dating, this practice cannot be performed efficiently and economically within the beyond-use dating (BUD) constraints of USP in the absence of compendial sterility testing.
In addition, federal and state (NC) regulations require that the following information appear on the label.
"Where possible, the beyond use date should be in accordance with allowances specified in the approved labeling.
However, reliable, published stability information is sometimes lacking for many types of drugs.