In his opening address to the Fianna Fáil Ard Fheis this evening, party leader Micheál Martin said there was "mounting chaos" in the health system under the stewardship of Minister James Reilly.
He said many hospitals would be pushed to the edge of viability under Government plans to overhaul the hospital system.
Calling for a restoration of the Treatment Purchase Fund, Mr Martin said it was a cost effective way of delivering for patients.
He also called for a No vote in the forthcoming referendum on the abolition of the Seanad.
While he acknowledged there was a need for Seanad reform, he said the referendum represented a power grab by the Government.
He said the Government was seeking more control while reducing scrutiny.
Up to 4,000 delegates are expected at the Fianna Fáil Ard Fheis which got underway at the RDS this evening.
Delegates will debate party reorganisation and abortion legislation as well as attending a range of workshops.
Among motions up for debate is one that seeks to give the membership more say in choosing a leader, and deciding whether to enter any coalition arrangement in the future.
Another motion that is less likely to be adopted, proposes that any TD who was sitting during the last government and who did not contest the last election, be barred from standing again.
Four motions committing the party to a pro-life approach and opposing abortion legislation are due to be debated tomorrow.
It is the second Ard Fheis since the party was nearly obliterated at the last general election.