Covid: How do I get a lateral flow test?
People are being encouraged by the Welsh government to use up lateral flow tests already at home before ordering more, due to high demand.
It comes as some users ordering rapid home tests were told online that no more kits were available.
The Welsh government said demand for the tests was "very high at present".
First Minister Mark Drakeford urged people last week to test themselves before mixing with others.
How do I get a lateral flow test (LFT)?
Attempts to order testing packs since just after 10:00 GMT on Monday resulted in some users receiving the message: "sorry, there are no more home test kits available right now".
The Welsh government said it expected any issues with meeting demand would be "resolved shortly".
"Lateral flow tests are readily available through pharmacies and community collection sites," it said.
Sudhir Sehrawat, a community pharmacist in Cardiff and Royal Pharmaceutical Society Wales board member, said his pharmacies have seen "increased demand" for test kits since Friday.
"We're finding the amount we can order each day isn't meeting the demand we're expecting," he said.
He said at Lakeside pharmacy in Cardiff, one box of 54 test kits was empty after an hour.
Mr Sehrawat he believed pharmacies were being put in a "restrictive process", only being able to order one box of 54 test kits per day.
"When you're in a busy area or you're the only pharmacy in the whole village, that is quite frustrating.
"Community pharmacy in general is doing its best to meet the challenge, we just need supply to meet demand.
"We're upsetting people by not meeting the demand for lateral flow tests, which the Welsh government have told people to do."
A Boots spokeswoman said there "may be a small number of stores" that are experiencing temporary shortages due to "higher demand in certain areas".
She said in these cases patients would be advised about other pharmacies nearby that have test kits in stock.
"Overall, we have plenty of stock of these tests across the UK and do not have any supply chain issues at present," she said.
The high street chemist said it provides lateral flow test kits at over 2,100 pharmacies in the UK.
Meanwhile, Amy Swarbrick a pharmacy technician at Knights Rhostyllen pharmacy in Wrexham, said they are experiencing no problems with ordering in lateral flow test kits.
"We are getting a lot of people asking for them, especially today," she said.
"The demand might outrun, but as it stands it is fine."
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