The HSE is under fire for spending over €500,000 on private ambulance services at South Tipp General Hospital last year.
This compares with just over €4,300 in 2011.
Sinn Féin is hitting out at the huge increase in the outlay for hospitals in Tipperary.
At Nenagh General it went from just €283 in 2012 to almost €70,000 in 2017.
The Health Minister is putting the increase down to the use of private ambulances to transfer patients which frees up the national fleet to deal with emergencies.
Sinn Féin general election candidate for Tipperary Ciara McCormack said the centralisation of ambulance control to Portlaoise is adding to the problems.