More than 340,000 NHS 24 calls were abandoned before the caller spoke to an operator during the first nine months of 2022.
Almost 120,000 of the dropped calls occurred during July, August and September, while July saw the longest single wait recorded for the year, with one caller waiting almost three hours to get through.
This is despite pressure on the NHS typically decreasing during the summer months.
Waits of two hours or more were also recorded in January, March, May, June and September.
The figures showed that, so far this year, the average time for waiting to speak to an operator stands at 19 minutes and four seconds.
In July, the average waiting time was nearly 24 minutes.
It comes after the launch of a new NHS 24 call centre in Dundee, which was announced in January as a move to “help facilitate the increase in demand for the NHS 24 service”.
The Scottish Conservatives, which submitted the Freedom of Information (FOI) request the data came from, has called on Health Secretary Humza Yousaf to “get a grip” on the country’s health system.
Scottish Conservative shadow cabinet secretary for health, Sandesh Gulhane said: “This is just another symptom of Humza Yousaf’s dire mismanagement of our NHS.
“It is shocking and deeply worrying that hundreds of thousands of Scots chose to abandon their calls to the NHS 24 helpline because it was taking them so long to speak to an operator.
“Patients are doing the right thing by calling NHS 24 for advice before attending A&E or their GP surgery. Yet, as it stands, Scots are waiting so long on the phone that a huge number are giving up before getting the crucial medical advice they need.
“Not only is this likely to pile even more pressure on our buckling A&E departments and ambulance service, but it’s extremely dangerous for patients who may need urgent medical advice.
“Unless Humza Yousaf gets a grip on Scotland’s floundering emergency health care system, we will only see more and more NHS services overwhelmed this winter.
“The health secretary must take urgent action to fix the interconnected crises in our NHS or many more patients will suffer over the coming months.”
The Scottish Government has been contacted for comment.
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