Certain types of EpiPens and their generic counterparts may fail or delay injection of lifesaving epinephrine for severe allergic reactions, the U.S. Food and Drug Administration warns.
Problems may occur in EpiPen 0.3 mg and EpiPen Jr 0.15 mg auto-injectors and authorized generic versions due to device malfunctions and user errors, according to the agency.
The devices may activate prematurely if the blue safety release is removed using sideways force, the FDA said. For example, a person may hold a device with one hand and try to remove the safety release with their thumb.
Before use, the device should be held in one hand and the safety release should be removed by pulling straight up with the other hand, the FDA said.
Some EpiPen devices also may have a blue safety release that is slightly raised, the FDA said. If that's the case, the device may activate prematurely, which could delay or prevent emergency use.
In addition, some EpiPen devices may not slide out of their carrier tube easily or at all due to a slight deformity on the tube's rim, the FDA said.
User errors can also delay or prevent injection. Users must remove the blue safety release and ensure that the orange needle-end of the device is in contact with the outer thigh before and during activation.
The FDA said the device must be pushed firmly against the outer thigh until it clicks -- which means that injection has started. It should be held in place for at least three seconds following activation.
"It is important for health care providers, patients and caregivers to periodically review the EpiPen user instructions and practice using the EpiPen trainer to ensure proper understanding and utilization of the EpiPen auto-injector," the FDA said in an agency news release.
The FDA called on pharmacists to inspect the devices before dispensing them to patients. It advised patients who have an issue with their auto-injector to contact EpiPen manufacturer Mylan at 800-796-9526 to get a replacement at no additional cost.
The U.S. National Library of Medicine has more on epinephrine injection.