Ticking sound with epinephrine autoinjector is normal

Use of this device requires training to assure it’s used correctly. Proper instructions are also printed on the pen. Despite this, we sometimes hear about people using the pen incorrectly, holding it upside down and injecting their thumb instead of their thigh muscle.

by Michael R. Cohen, R.Ph.

Published Nov. 20, 2014, 9:21 a.m. ET

Epinephrine is a medication that's important to have on hand if you or a loved one has severe allergies to a particular substance like certain medications, bee stings, etc. The good news is the drug can be prescribed by your doctor as an autoinjector that can be carried on the person at all times, kept with a parent of a child who suffers from severe allergies or even held in a strategic location, like your child's school.

People who use autoinjectors are likely to be familiar with a product called EpiPen or EpiPen Jr. for kids. Use of this device requires training to assure it's used correctly. Proper instructions are also printed on the pen. Despite this, we sometimes hear about people using the pen incorrectly, holding it upside down and injecting their thumb instead of their thigh muscle.

There's another autoinjector called the Auvi-Q that's designed to prevent this type of error. It also facilitates proper injection by talking you through the process. There are digital voice instructions throughout the injection process beginning after the device is activated.

Auvi-Q has LED light cues that flash green during injection and red after the device has been used. Prior to injection, Auvi-Q must be removed from its case and the needle guard must be pulled off. You can view the Auvi-Q demonstration here. The device will make a distinct click and hiss sound when activated.

According to the package insert, the base that houses the needle will lock in place after injection so it can't be reused. The voice instruction system will continue to remind the user that the Auvi-Q has been used, and its LED lights will continue to blink red until the cover is put back on or until the battery eventually runs out. But if the cover is not replaced on the device, the electronic voice speaker makes a "ticking" sound as the battery drains and can't fully power the device.

This sound might alarm someone who thinks the ticking noise means that a calamitous event is about to happen. Emergency department staff alerted us to this recently after the family of a patient who used an Auvi-Q auto-injector brought it in without the case. Staff later heard a ticking sound coming from a needle disposal box where the device had been discarded. This is normal and no, it's not going to explode.

We can assume that many patients and healthcare staff will not replace the device back into the case after emergency use. Therefore, know that if the cover isn't replaced the device will emit a ticking sound as the battery dies. We have notified the companies about this ticking sound, which may cause hospital staff to call security if the source of the ticking noise is not realized.