Lesley Griffiths announces £82m for under-pressure NHS
The NHS in Wales will get an extra £82m to help it balance the books.
A bigger-than expected increase in emergency hospital admissions for patients aged 85 and over was putting "significant strain" on services.
The Welsh government said extra "contingency funding" would help the NHS cope with pressures.
Health minister Lesley Griffiths fiercely denied the money was a "bailout" for local health boards (LHBs).
She has previously warned LHBs not to expect bailouts at the end of the year and said they must hit their financial targets.
The extra funding comes after the Wales Audit Office (WAO) forecast the NHS is likely to be £70m in the red by the start of the next financial year in April 2013, with a worst-case scenario of a £130m deficit.
Appearing before a committee of AMs on Wednesday, Mrs Griffiths said she was responding to "unprecedented" pressures on the NHS this year, particularly in emergency care.
A mid-year review by officials in her department found the increased number of elderly patients needing to be seen at hospital was bigger than predicted and could have a knock-on effect by delaying treatment for other patients.
The extra funding is roughly equivalent to 1.5% of the entire NHS budget.
The minister said: "While the review shows a number of quality improvements this year within NHS Wales, changing demographics are having a greater impact on the NHS than originally forecast.
"Disruption to emergency services over a sustained period therefore has an effect on planned services, meaning a risk of targets being missed.
"This additional funding will allow the NHS to manage current pressures and maintain quality of care."
She added she was looking at providing more "flexibility" for LHBs, who have a legal duty to break even.
The Conservatives' shadow health minister Darren Millar said the extra cash might not be enough if the bleakest assessment of the LHBs' finances proves correct.
He said: "NHS funding is an unsustainable disaster. Contingency funds have now become routine accounts and bailouts commonplace."
Plaid Cymru said the boards should be directly accountable to the assembly's cross-party health committee, with regular monitoring to make sure their finances do not "spiral out of control".
Plaid health spokeswoman Elin Jones said the government "has simply not got a grip on the health service".
Welsh Liberal Democrat leader Kirsty Williams said: "I struggle to see how this can be described as anything other than a bailout.
"Simply rejigging money around is not going to solve all of the problems in our NHS."
The Welsh NHS Confederation, which represents health boards, welcomed the funding and said the NHS is trying to save £220m this year, on top of £600m over the last two years.
Helen Birtwhistle, its director, said: "The NHS continues to operate in an extremely difficult financial environment but all staff are working very hard to find necessary savings at the same time as making improvements to the safety and quality of care."
Meanwhile the prime minister has attacked Labour's running of the health service in Wales.
During Prime Minister's Questions, David Cameron told MPs: "The Labour Party is in charge in Wales and they have cut the NHS in Wales by eight per cent.
"As a result waiting times are up, waiting lists are down, quality is down, that's what you get with Labour and the NHS."
Mr Cameron was responding to Labour claims that he had broken his promise to increase spending on the NHS in England in real terms.