NHS Tayside has been branded a “financial basket case” after it was revealed the health board has spent more than £15 million on agency staff since 2013/14.
The figure was revealed in a freedom of information request.
In 2013/14, NHS Tayside paid £2.4 million to agencies.
But the figure rose to £4.2 million in 2016/17.
Agency costs for the current financial year to January already total more than £2.7 million.
Kevin Keenan, leader of Dundee City Council’s Labour group, urged the health board to address the issue.
He said: “We hear on a regular basis that NHS Tayside is in a financial struggle.
“Of course, the NHS needs staff to operate — however it may be paying over the odds to agencies who are cashing in from this.
“The main issue with NHS Tayside is it seems to be a financial basket case and we need measures put in place to aid that.
“Overspends seem to just grow and grow, they seem to run away with cash. A lot of things need to be addressed in the health service.”
NHS Tayside has repeatedly required bailouts from the Scottish Government.
A report by Sir Lewis Ritchie, head of the group set up to nurse NHS Tayside back to financial health, said it is making progress in reducing its deficit but warned it will be harder to find savings in coming years.
Recently, it was revealed NHS Tayside was paying private medical company Synaptik to help bring down waiting times in its neurology department at Ninewells Hospital.
A spokeswoman for NHS Tayside said reducing the reliance on agency staff is a key priority for the health board.
She said: “In the coming financial year, NHS Tayside will continue to respond to the challenges of continuing to deliver high-quality, safe and effective healthcare to our population, while redesigning our services so they are fit for the future.
“Reducing the use of supplementary staffing will remain a key priority.
“NHS Tayside has a proactive approach to reducing reliance on use of supplementary staffing and actions continue to be taken to manage the appropriate use of temporary agency staff and reduce overall costs.”