You probably already know that epinephrine is the medication of choice for life-threatening allergic reactions (anaphylaxis). In fact, the Centers for Disease Control (CDC)* recommends epinephrine using as initial treatment for these allergy emergencies.
Epinephrine auto injector becomes handy while injecting a measured dose or doses of epinephrine. But, are they useful when they freeze?
A study by the American College of Allergy, Asthma, and Immunology (ACAAI) Annual Scientific Meeting has now offered the answer to the question. The study suggests that the device will still work but it’s better to use a ‘thawed’ device than nothing at all.
Julie Brown, MD, abstract author said, “Since many people who live in cold climates use an EAI, we wanted to explore the effects of freezing on how an EAI functions. Lead author and researcher Alex Cooper took 104 same-lot pairs of EAIs and froze one of each pair for 24 hours, while the other was kept at recommended temperatures as a control.”
“Once the frozen devices were thawed, they and their controls were injected into meat. The meat and devices were weighed both before and after firing. The change in meat weight and device weight was similar between frozen-thawed devices and their controls, indicating that freezing did not affect how the EAIs functioned once they were thawed.”
Allergist Anne Ellis, MD, chair of the ACAAI Anaphylaxis Committee said, “Many people who use EAIs have been concerned about the current shortage of EpiPens. It’s important for those who have severe, life-threatening reactions to their allergies to have confidence in the EAIs they carry and know they’ll work in an emergency. This study showed that even when an EAI has been unintentionally frozen, the risk is low that it will malfunction.”
“The study did not examine the amount of epinephrine remaining in the solution after it had been frozen. We know epinephrine is a somewhat unstable compound, and that’s why the shelf life of EAIs is so short.”
The ACAAI Annual Meeting is November 15-19, 2018 at the Washington State Convention Center in Seattle.
Abstract Title: The Effects of Freezing on Epinephrine Auto-Injector Device Function
Author: Julie Brown, MD, Alex Cooper