Evaluation of temperature excursions from USP <659> recommendations during mail transit

Abstract

Background: Patients use mail delivery as a convenient alternative to acquiring medications in person. Federal laws require nonspecialty oral medications to be stored at controlled room temperature during distribution; however, no laws or regulations govern temperature requirements for medication transport among patients, which may expose medications to harmful temperature excursions.

Objective: The purpose of this study was to evaluate temperature excursions during mail transit based on the shipment method, carrier, and season.

Methods: This prospective study monitored temperature fluctuations during simulated mail transit between New Jersey, California, and Tennessee over winter (December 2019-February 2020) and summer (August-September 2020) time frames. Packages with data-logging thermometers were shipped to 3 U.S. destinations via 3 common mail carriers and 2 popular shipping methods. Three packages were mailed for each combination of season, carrier, and shipping method, representing 36 individual packages. The primary end point was percent of transit time out of range (OOR) based on the United States Pharmacopeia <659> recommended range, 68°F to 77°F. Additional end points include package transit durations and extreme temperatures.

Results: Evaluated packages spent an average of 68.3% of transit time OOR. In winter, 3-day and next business day packages spent similar time OOR (80.1% vs. 78%). In summer, 3-day packages spent more time OOR compared with next business day shipping (43.1% vs. 13.6%). Mean transit time was statistically significantly longer for 3-day packages (406.6 hours vs. 303.1 hours; P < 0.0001). Mean winter transit time was statistically significantly longer than summer (475.7 hours vs. 233.9 hours; P < 0.001) regardless of the shipping method. The minimum and maximum temperatures recorded were 5.1°F and 102.3°F, respectively.

Conclusion: Package temperatures were outside of the recommended range for most of the transit time regardless of the shipping method, carrier, or season.