Millions of patients in the UK do not have access to a GP at night, an investigation has revealed.
At least six health boards were forced to operate out-of-hours services without a single family doctor on occasion last year.
Sick patients were tended to by paramedics or an experienced nurse instead.
A national snapshot shows the number of night shifts where a doctor was unavailable has almost trebled from 57 in 2017 to 146 in 2018, according to figures in the Daily Mail.
Meanwhile, serious incidents in out-of-hours care – where care has fallen way below that expected – have risen by a quarter.
Experts have blamed a shortage of GPs and lack of cash to tempt already overworked doctors into covering antisocial hours.
Dr Richard Vautrey, of the British Medical Association, said the GP workforce is under severe strain, with the number of doctors continuing to fall despite repeated government pledges to recruit more.
“Combined with rapidly increased demand from a population with more complex health needs, this staffing shortfall means workload has reached unmanageable levels,” he warned.
The figures follow an investigation by GP magazine Pulse. Of the 79 health authorities which responded to the Freedom of Information requests, seven admitted to having to run at least one shift with no doctor in the last two years because of staffing pressures.
The majority occurred at one of three regions in Wales, alongside two clinical commissioning groups, or CCGs, in England and two in Scotland.
Hywel Dda University Health Board, which covers 384,000 patients, had no GP cover 125 times last year – almost three times the 42 times it operated without a GP in 2017.
In England, two CCGs reported struggling to fill out-of-hours shifts in 2018. Tower Hamlets, which looks after 331,000 patients in east London, experienced the problem three times in 2018, and North East Lincolnshire, which covers 169,000 patients, had two instances last year.
In Scotland, one health board – NHS Borders, which covers a population of 115,020 – responded with figures showing the problem is worsening. Across 2016 and 2017 it had only two occasions of no GP cover, rising to eight in 2018.
Collectively, more than 2.1 million patients were left without an out-of-hours GP at least once.