A product recall has been issued due to a problem with a batch of EpiPens, which are used to treat allergic reactions.
It's understood the problem relates to them having an issue with their injector.
The affected devices are 300 microgramme pre-filled pens, with an expiry date of May 2017 and lot number 5FA665G.
The Health Products Regulatory Authority is asking every EpiPen user to check the details on their devices.
If they're affected they should be returned to their pharmacy where a replacement will be given for free.
