Meanwhile, Dr Surachok Tangwiwat, Food and Drug Administration (FDA)’s deputy secretary-general, said the agency has given four companies the green light to sell test kits over the counter.
He said consumers must check if the test kit has a “for citizens” stamp before purchasing.
"Rapid antigen test kits will also be available at hospitals, clinics and pharmacies from Friday," he said.
He also advised people against buying Covid-19 test kits online, saying that it is against the law to advertise these devices without permission.
“People who find test kits being advertised can call the 1556 FDA hotline,” he added.
Dr Thongchai Keeratihattayakorn, permanent secretary of the Public Health Ministry, said people who are not at risk should not waste their money on these kits.
Dr Supakit Sirilak, director-general of the Department of Medical Sciences, explained that antigen tests use saliva or samples from the nose cavity, while the more accurate antibody test uses blood samples.
He also advised at-risk people who test negative to take the antigen test again three to five days later and isolate themselves.
"Those who test positive, should inform public health agencies near their home and separate themselves. They should seek medication if they have trouble breathing,” he said.
He also advised people to disinfect used test kits and put them in a bag before discarding them.