Tests recently went on sale at Lidl.
The World Health Organisation says people could be making "inappropriate decisions" if they rely on the result from an antigen test.
The tests, which recently went on sale in Lidl, get a result quicker - but aren't as accurate as other types such as PCR.
The Chief Medical Officer has strongly recommended against people buying and using antigen tests themselves.
Dr Margaret Harris from the WHO says people could get false reassurance from the result:
.
The World Health Organisation says antigen tests are a useful tool that can be used in some settings.
Dr Harris says they can play a role in some instances:

Body Found At Wheatfield Prison Sparks Garda Investigation
Families Could Face €1,000 Rise In Annual Food Bills Amid Farming Crisis
Over Half of Cigarette Packs Surveyed In Newbridge And Naas Had No Irish Duty Paid
Celbridge Brewery CEO Warns Of Mounting Costs Facing Craft Beer Sector
Amhrán na Laoch Songwriting Competition Confirmed for Irish Music Month 2026
Government Announces Major Overhaul of Anti-Money Laundering Rules
Maynooth University Hosts Special Solar Eclipse Event This Evening
Johnstown Mother Says Today's Solar Eclipse Means Something Extra Special For Her And Her Son