Almost 400,000 patients called the NHS 111 helpline in the last week, official figures reveal.
This is the highest volume of calls this year and an increase on a fifth compared to the previous week.
Yet more than 35,000 of these patients hung up because their call was not answered quickly enough.
The number of unanswered calls was double that of the previous week while the volume of calls rose by a fifth
This is more than twice the number compared to the week before and suggests the helpline is struggling to cope with demand.
Elsewhere, several A&E units having been urging the public to stay away as they are extremely busy.
They include the Derriford Hospital in Plymouth where patients were warned they would face a six hour wait to be seen.
The Royal Cornwall hospital, the North Cumbria University Hospitals and the Bradford Teaching Hospitals also urged patients to think-twice before showing up.
Figures from NHS England also show that half of children’s intensive care units were dangerously full in the run-up to Christmas.
The worst day was on December 19 when 18 of the 38 paediatric intensive care units in England were completely full, with no spare beds.
But other measures of hospital pressure have improved over the Christmas period and NHS bosses praised the hard work of their staff.
They include bed occupancy which were 84.2 per cent on Christmas eve – the last count – down from 95.3 per cent a week earlier.
Only six hospitals imposed A&E ‘diverts’ – whereby they reroute ambulances to other hospitals during busy periods – down from 30 the previous week.
Almost 400,000 patients called the NHS 111 helpline in the past week – but 35,000 hung up because their call was not answered quickly enough
Some 812 beds were closed to the winter vomiting bug, down from 1,071 beds the previous week.
These latest figures cover the week up to the 24th of December, the pressures on the NHS are typically at their highest in early January.
There were a total of 396,262 calls to the NHS 111 helpline but 35,012 patients hung up because they weren’t answered within 30 seconds.
An NHS England spokesman said: ‘The NHS has been busy in the run up to Christmas, with record levels of 111 calls.
‘Despite this, ambulance handover delays, bed occupancy and norovirus levels all dropped thanks to the hard work of NHS staff.
‘Additional winter funding will be used to open over 1,500 additional beds in the coming weeks, and the public can continue to play their part by using local pharmacies and NHS 111 for medical advice, along with the GP appointments available 8am-8pm throughout the holiday period.’
But Jonathan Ashworth MP, Labour’s Shadow Health Secretary, said: ‘Despite the very best efforts of our brilliant NHS staff, our findings today reveal a distressing picture of the unprecedented pressures on paediatric intensive care units across the country.
‘With the New Year fast approaching and demand likely to further increase, the Government must urgently explain in the New Year how they will avoid another intolerable slump in care this winter.’