The Health Sciences Authority (HSA) is investigating the unauthorised distribution and supply of antigen rapid test (ART) kits manufactured by Singapore-based company SG Diagnostics.

They are meant for professional use in "healthcare settings by healthcare professionals who are trained to administer the test and validate the results", the authority said yesterday in response to queries from The Straits Times.

The kits should not be used by untrained lay users, who may derive inaccurate results, the HSA said, adding that this could lead to them not getting timely treatment if they have Covid-19, or failing to take necessary precautions to protect themselves and the people around them.

SG Diagnostics had urged consumers in an advertisement in ST Classifieds on Tuesday to stop using the product.

When ST called the SG Diagnostics hotline listed in the ad, an operator said buyers are advised to return the ART kits to suppliers and ask for a refund.

ST understands that while the kits can already be bought over the counter in some countries, they have not yet been approved for general sale here.

Sellers had put up listings on e-commerce platforms such as Shopee, Lazada and Carousell, pricing a box of two kits at about $18. Listings for group orders were also seen on shopping platform WeBuy. Many of the listings have been taken down.

The kits were also seen to be for sale in physical stores such as IT retailer Challenger.

The HSA said regulatory and enforcement actions under the Health Products Act will be taken against any party involved in unauthorised distribution and supply of the kits.

It advised consumers to purchase and use self-administered ART kits approved in Singapore.

The list of kits can be found on the HSA's website.

For inquiries on returning the kits, consumers should call the SG Diagnostics hotline on 8030-5766 or send an e-mail to info@sgdiagnostics.com