A primary care trust (PCT) which covers Suffolk and Norfolk is facing a £9.9m budget deficit by the end of the year, board members have heard.
The Great Yarmouth and Waveney PCT, which already had a shortfall of £2m, had been expected to break even but now is facing a host of new costs.
These include £3m of unplanned hospital charges it had to pay for.
The PCT said it is looking at ways of reducing "unnecessary expenditure" and will ensure high quality health care.
'Inroads into debt'
At an extraordinary meeting of the PCT on Wednesday the board heard the trust also faced a £1m shortfall on the income from dental patient charges and £1m extra payments to primary care contractors.
The merger of the Great Yarmouth and the Waveney PCTs is set to cost up to £2.1m.
Mike Stonard, PCT chief executive, said: "We have adopted a proven financial recovery process that has previously delivered significant results elsewhere in the NHS and I believe we can make significant inroads into this figure by reducing unnecessary expenditure.
"We will take great care to ensure we continue to provide high quality health care services to the people of Great Yarmouth and Waveney."