In the heat of summer, patients who carry EpiPens should think twice about leaving them in their car to avoid a decrease in their effectiveness
A small pilot study, published in The Journal of Allergy and Clinical Immunology: In Practice, found that even a single, short-time exposure to heat in a car during a sunny day can decrease epinephrine concentration in autoinjectors. If such degradation turns out to be progressive or cumulative, it could result in significant underdosage of epinephrine during anaphylaxis.
“We want to urge everyone to never expose their EpiPens to high temperatures or leave them in their vehicles,” said first author Dr Piotr Lacwik. “Underdosage during an anaphylaxis episode can have deadly consequences, so it is important patients keep autoinjectors stored correctly.”
Epinephrine autoinjectors (EAIs) have recommended storage temperatures of 20–25°C, with excursions of 15–30°C permitted. During the summer months, however, EAIs may be exposed to high heat accidentally when being stored in locations with unregulated temperatures, such as inside a vehicle.
Alarmingly, the study concluded that despite the decrease in epinephrine concentration in the EAI there were no recognisable changes in the solution’s appearance.
“This is a very small pilot study,” Dr Lacwik said, “but it’s an excellent reminder for patients to take great care when carrying their autoinjectors.”
For their safety, patients should always keep their EpiPens with them and refrain from leaving them inside a car during warm weather, even for a short time.
The Journal of Allergy and Clinical Immunology: In Practice is the official journal of the American Academy of Allergy, Asthma & Immunology.