Embattled health chiefs in Tayside last year shelled out nearly £500,000 on locum doctors, amid a growing GP recruitment crisis.
The amount spent on stand-in staff throughout 2016/17 is more than the previous four years combined.
The dramatic rise in spending, revealed to the Scottish Conservatives following a Freedom of Information request, is thought to be as a result of three practices being handed back to the health board.
Across Scotland, GP surgeries are reverting to board control, which critics argue delivers poor value for money.
The Tories have launched a Save Our Surgeries campaign, which is calling for ring-fenced funding and more GP training places.
Mid-Scotland and Fife MSP Liz Smith said: “Unfortunately, this increase in locum funding could just be the start for NHS Tayside as many GP surgeries are considering reverting to board control.
“If a similar increase is witnessed next year then locum GP funding could represent a funding black hole for NHS Tayside.”
She added: “Ultimately, only by increasing the number of GP training places and increasing flexibility will the GP crisis be averted and it’s time that the Scottish Government took meaningful action on this.
“Our Save Our Surgeries campaign is clear – 11% of NHS funding should go straight into general practices so we can help local practices recruit and retain staff.”
The amount paid to doctors for a four-hour shift – £210 – remains unchanged for the past three years.
An NHS Tayside spokeswoman said: “All boards across Scotland are facing a current national shortage of GPs and NHS Tayside is no exception. However, we are taking steps to recruit and retain GPs and look at different ways of delivering care out in our communities.”
She said: “In the past few years, NHS Tayside assumed responsibility for three practices – Lochee and Whitfield Health Centres in Dundee and Brechin Health Centre – which saw the Health Board provide primary care services and GP cover to nearly 15,000 additional patients.
“A major reason for these practices transferring their contracts back to NHS Tayside was due to ongoing challenges to recruit GPs. The rise in GP locum costs can be attributed to these practices.”
She added: “NHS Tayside has worked closely with the three practices to support new models of care with an expanded multidisciplinary team, and offering innovative schemes to attract new GPs to the area.
“This has resulted in successful recruitment of new GPs to all three practices.”
• Locum GP spend on board-run GMS practices:
2012-13 = £19,338
2013-14 = £51,572
2014-15 = £34,873
2015-16 = £187,007
2016-17 = £459,780
• Per the totals above, the largest amounts paid per four-hour session were:
2012-13 = £200
2013-14 = £200
2014-15 = £210
2015-16 = £210
2016-17 = £210