Although concentrations of epinephrine weaken over time, significant amounts of epinephrine are retained in EpiPens long after their expiration dates, and the dose available 50 months after expiration will likely have a beneficial pharmacologic response, according to a research letter published in Annals of Internal Medicine.
“Interest and outrage have been mounting over dramatic price increases for the emergency-use epinephrine autoinjection device EpiPen (Mylan),” F. Lee Cantrell, PharmD, from the California Poison Control System in San Diego, and colleagues wrote. “Since 2007, the price of this potentially lifesaving medication has risen more than 400%. This sharp increase has caused patients to ask health care practitioners whether they can use expired EpiPens because they cannot afford to replace them.”
Cantrell and colleagues examined the potency of EpiPens 1 to 50 months past their expiration date. Over 2 weeks, they collected 31 unused, expired EpiPens (epinephrine, 1 mg/mL) and nine EpiPen Jrs (epinephrine, 0.5 mg/mL) from patients and practitioners at a community clinic to analyze for color changes, expiration date and epinephrine concentration.
They used liquid chromatography–tandem mass spectrometry to quantitatively analyze two separate samples of each device’s epinephrine concentration. Two transitions were used to monitor epinephrine. In addition, epinephrine-d6 was used as an internal standard to quantify epinephrine by isotope dilution.
Data showed that none of the EpiPens were discolored. Furthermore, at least 90% of the stated amount of epinephrine was retained in 65% of EpiPens (n = 19) and 56% of EpiPen Jrs (n = 5).
“The process for establishing expiration dates for EpiPens should be revised, and ... in the setting of outpatient anaphylaxis without other therapeutic alternatives, patients and caregivers should consider the potential benefits of using an expired EpiPen,” Cantrell and colleagues concluded. – by Alaina Tedesco
Disclosure: The researchers report no relevant financial disclosures.