This report assess the stability and shelf life of naloxone under varying conditions, finding that it remains chemically stable following exposure to heat or freeze-thaw cycles after 28 days. This indicates that naloxone will remain effective in storage and distribution systems such as vending machines and mobile vans well after its nominal expiration date.
Lai D, Pham AT, Rao PPN, Beazely MA (2019). The effects of heat and freeze-thaw cycling on naloxone stability. Harm Reduction Journal 16:17.