The highest number of abandoned calls occurred in September 2021 when 68,119 were left unanswered, according to data obtained by the Scottish Conservatives.

Over the festive period, in December, on more than 46,000 occasions callers were unable to speak to anyone.

The Conservatives said that "shockingly" on January 3, very nearly half of all calls (49.7%) were abandoned, accounting for more than 7,000 abandoned calls on that day alone.

READ MORE: Scottish A&E waiting times suffer 'wholy unacceptable'decline

The Scottish Government said it recognised that some patients had faced longer waits due to increased demand at peak times.

NHS 24 said that some callers might choose to end the call themselves as an automated message directs patients to other health services including 999.

However, Jackie Baillie, Labour's health spokeswoman, said the "damning" statistics showed thousands of Scots had missed out on medical help.

A separate investigation by her party found that between October 2021 to January 2022, 25% or more of daily calls to NHS 24 were not connected on several occasions, with at least a quarter abandoned between the December 18 and January 5.

Shadow Health Secretary Dr Sandesh Gulhane accused Health Secretary Humza Yousaf of "taking his eye off the ball" saying the figures were especially concerning, given that patients have been urged to call NHS 24 before turning up at emergency wards to ease the strain on over-stretched A&E departments.

He warned this had created another dangerous bottleneck in Scotland’s NHS, which is now at “absolute breaking point”.

He said:  “The number of abandoned calls to NHS24 is astonishing and deeply concerning.

“Patients have been encouraged to use NHS 24 as a first port of call before going to Scotland’s desperately over-stretched A&E wards, so some of these calls will relate to serious conditions.

READ MORE: New NHS 24 centre opens in Dundee to increase capacity 

“This has created another dangerous bottleneck in our NHS, which is at absolute breaking point under the SNP. Potentially life-threatening incidents are likely to have been missed as a result of so many calls not being connected.

“Having an average of almost 50,000 calls a month going unanswered is completely unacceptable and unsustainable. It is systematic of a health service in crisis on the SNP’s watch despite the heroic efforts of those working and volunteering in our NHS."

He added: “These figures must act as a catalyst for the SNP’s Health Secretary to urgently outline a plan that will guarantee patients can be confident their calls to NHS24 will be answered at all times.”

NHS 24 said the service had faced an "unprecedented" growth in demand due to the pandemic with Covid symptoms accounting for approximately 20 – 25% of calls during the period in question.

A spokeswoman added: "In addition to the increase in demand due to Covid, NHS 24’s 111 service was required to rapidly move to from a predominantly out of hours service, to a 24/7 operation.

"There has been  a 45 – 50% increase in calls to NHS 24 since early 2020.

"This unprecedented growth in demand for the 111 service means that, at times, people have experienced a longer wait time for their calls to be answered.

"Our automated telephone messaging system gives callers options of alternative routes to safe and effective care at the start of the call, which may be better aligned to their individual needs.

"This clear signposting means people may choose to end their call to 111.

"For example, in the case of an emergency, callers will always be advised to dial 999. Someone calling for information about the Omicron variant may choose to hang up and dial the COVID information line."

Scottish Labour's health spokeswoman Jackie Baillie described the figures as "unacceptable".

She said: “These damning statistics are clear – the SNP’s failure to support NHS 24 has led to thousands of Scots missing out on medical help.

“Throughout the winter A&E services, NHS 24 and ambulance services have been in crisis but Humza Yousaf has looked the other way.

“Staff have worked tirelessly, but with thousands of Scots in need being left hanging on the telephone it is clear that greater support is needed.

“This is unacceptable. Lives are being lost now because of the SNP’s failure to support NHS staff."

A Scottish Government spokesman said: "NHS 24 works hard to ensure calls to its 111 service are answered as quickly and safely as possible, however we recognise that during the pandemic, some patients have experienced longer wait times than normal, due to increased demand during peak periods.

“As a result of increased demand and changes to service delivery we have recently increased funding to NHS 24 by over £20 million for additional recruitment and the addition of a brand new call centre in Dundee, which opened in December.

"We will continue to support the service as it expands both its services and workforce."