Researchers who analysed 40 date-expired EpiPens and EpiPen Juniors have discovered that they were still effective beyond the stated expiry date.
They found that although the emergency-use epinephrine auto-injectors lost potency over time, they could still prevent anaphylactic shock.
Pharmacist Frank Lee Cantrell and his team analysed 31 EpiPens and 9 EpiPen Juniors — all were between 1 month and 50 months past their expiration dates. The team tested the pens for their concentration of epinephrine.
They found that 19 (65%) of the expired EpiPens and 5 (56%) of the expired EpiPen Juniors contained at least 90% of their stated epinephrine. All the products contained at least 80% of their labelled concentrations.
Writing in Annals of Internal Medicine
(online, 9 May 2017), the researchers say their findings are important because all the date-expired pens were capable of meeting the necessary and recommended doses for out-of-hospital treatment for anaphylaxis.
“Our data show that EpiPen products can retain substantial amounts of epinephrine well beyond their expiration dates,” they say.
“Although we observed declining concentrations of epinephrine over time, we expect that the dose available 50 months after expiration would still provide a beneficial pharmacologic response.”
The authors also suggest that the “process for establishing expiration dates for EpiPens should be revised and that, in the setting of outpatient anaphylaxis without other therapeutic alternatives, patients and caregivers should consider the potential benefits of using an expired EpiPen.”