For better patient compliance and easier distribution, some drug products are frequently repackaged from their original containers into unit-dose packages by pharmacists or commercial repackagers. The USP indicates that for non-sterile solid dosage forms packaged in unit-dose containers, the beyond-use date shall be 1 year from the date the drug is packaged into the unit-dose container or the expiration date on the manufacturers container, whichever is earlier, unless stability data or the manufacturers labeling indicates otherwise. Due to differences in moisture permeation, thermal susceptibility or surface chemistry of the new packaging material when compared to the original, the stability of a repackaged drug product can differ from that obtained from original container. This concern prompted us to study the stability issues associated with certain repackaged products. This chapter will highlight some of the findings in our research laboratory.
