People have been turning up to pharmacies for lateral flow tests 'every five minutes' over the Christmas period - and have often been unable to get one.
Leyla Hannbeck, chief executive of the Association of Independent Multiple Pharmacies, said it has been a 'huge problem' in recent weeks.
She said patients are often unable to find the Covid tests in pharmacies because of 'patchy and inconsistent' supplies.
She added that the current daily influx of 900,000 tests has not been meeting the high demand.
READ MORE: The one thing experts are asking people to do when taking a lateral flow test
Leyla Hannbeck told the BBC’s Today Programme: “What our members are telling us is that demand for the lateral flow tests is very high at the moment due to the current guidelines around self-isolation.
“Pharmacies are reporting that every five minutes, approximately, somebody comes into the pharmacy asking for a test.
“But, unfortunately, because of the issues around supply being patchy and inconsistent, it means that those who come for the test don’t always get it, which is very stressful not just for the pharmacy team but for the patient.
“The scale of the problem is huge because the demand is high, because of the current guidelines.
“People are doing the responsible thing by wanting to be tested and we are in the Christmas area of time, and the New Year is just around the corner and people want to be with family and friends.”
"We want to make sure that the message is clear to the Government that the supply needs to be consistent,” she added.
“People can get it easily from pharmacies if the supply is consistent.”
This comes after lateral flow tests became unavailable for home delivery again yesterday, with people urged to go to pharmacies instead.
This was at least the sixth time the tests have been unavailable for delivery.
Work and Pensions minister Chloe Smith said people should 'persevere' in their efforts to secure Covid tests.
She told BBC Breakfast: “Of course, what we’re seeing is increased demand for testing, which is good and sensible because that’s part of people having been cautious, I think, and being sensible around Christmas and around New Year.
"So, we’re seeing spikes of demand.
“What we’ve done in response to that then is double the delivery capacity – so we’ve taken action to make sure that people can get testing kits delivered to them at home.
"An additional method to that, of course, is going to a pharmacy.
“I quite understand that people will be wanting to make sure that the testing kits are there – that follows on from people having been doing the right thing in being cautious and in wanting to be tested, perhaps before big events or family gatherings.
“What I would say is to please persevere with either making use of your friendly local pharmacy or using the delivery method on the Gov.uk website.
“Even whilst there have been periods of great demand on that, and every so often we’ve had to replenish the means behind the scenes there, that is happening and the delivery is occurring."
The UK Health Security Agency has said there are now nearly 900,000 test kits being supplied per day – which is double the delivery capacity seen before December 18.
The UKHSA has said tests may be temporarily unavailable on the government website at points throughout the day due to “exceptionally high demand” and urged people not to order more tests before using the ones they have.
A spokesperson said: “During periods of exceptional demand there may be temporary pauses in ordering or receiving tests, to ensure we manage distribution across the system and support changing requirements for LFD and PCR tests.
“Reduced postal schedules also impact on delivery capacity over the Christmas period.
“Rapid tests are available to order directly to people’s homes via gov.uk and availability is refreshed regularly throughout the day.
“We encourage people to re-visit the site every few hours if they are unable to order tests as more will become available – and to please ensure they are making use of any tests they already have at home before ordering or collecting more.”
