The North-Eastern Health Board, whose area recorded a 12 per cent increase in population in the latest census, is € 9 million over budget.
The board's chairman, Mr Declan Breathnach, says that the Department of Health must step in to ensure that it is able to continue to provide services.
Figures for the first six months of this year show more people have used services in the health board's five acute hospitals in Drogheda, Dundalk, Navan, Cavan and Monaghan.
The board now has 200 more staff than it had budgeted for by the end of June. A report from its finance officer says that outside of wages, the excess cost of medical items, where inflation is estimated to exceed 10 per cent, "is causing severe budgetary difficulties".
It is critical of expenditure being brought back in line for the second half of the year to avoid carrying forward any deficit to next year. This could mean deferring some proposed developments as well as reducing staff numbers.
Mr Breathnach attributed the budget overrun to meeting the health needs of an ageing population, asylum-seekers, childcare and transport. "The Department of Health and the Minister have to take cognisance of the fact that we have the largest increase of any health board and we have been trying to live within our means since 1986, when we knew our population was greater than that forecast by the Central Statistics Office," he said.
Transport costs were €1.45 million over budget, while pathology costs were €860,000 over and office expenses and medical/surgical supplies were both more than €600,000 over budget.
In the hospitals there had been an 18 per cent increase in day cases, a 12 per cent rise in attendance at casualty departments and a 13 per cent rise in births. The largest increase was 33 per cent in renal dialysis.
The report says that the increase in the size of the indigenous population, increased births, an increase in the elderly population and an increase in non-nationals coming to live in the health board area have had the greatest impact on the board.