Medics have warned the Government they have been hit by a wake-up call after a European court ruled junior doctors' working hours are illegal.
The Irish Medical Organisation (IMO) said it will use the interim finding that training hours for non-consultant medics is a breach of the working time directive in order to ratchet up pressure to get the working week reduced.
The body had lodged a complaint with the European Commission over excessive rosters for junior doctors over the last two years and ramped up their campaign in 2013 with a 24-hour stoppage by medics in hospitals.
Eric Young, assistant director of industrial relations at the IMO, said the decision was a significant vindication for non-consultant hospital doctors (NCHDs) and a significant rebuke for the health service in Ireland.
"This verdict must be a wake-up call for the Irish Government. For years they have forced NCHDs to work excessive hours and that has caused immense hardship and helped create the morale crisis which is forcing young doctors to emigrate from Ireland," he said.
Rosters for some junior doctors in a hospital can still include a 32-hour shift. It is also not uncommon for them to be on a 24-hour shift. The European working time directive sets a bar of 48 hours a week.
The ruling found the Government had breached European law by not counting training hours carried out by junior doctors along with actual working time on the wards.
"We should not have to rely on intervention from Europe on matters like this," Mr Young said.
"Ireland's health service managers must take responsibility and fulfil their legal obligations to employees and to ensure that patients are dealt with in a safe environment."
The IMO said health chiefs had given a commitment that hospitals would comply with EU rules by the end of last year.
The group estimates 230 non-consultant hospital doctors in more than 21 hospitals are working more than 24-hour shifts and that one third of junior doctors routinely work more than 48 hours.
The ruling was issued by the advocate general of the European Court of Justice, an interim decision which is not final or binding but which is normally upheld in the ultimate verdict.
The Department of Health is examining the decision.
Health Minister Leo Varadkar insisted that good progress has been made in bringing doctors' rotas into line with the working time directive and that officials were close to ending 24-hour shifts.
"Reducing average working times to 48 hours or less per week remains a challenge, particularly in smaller hospitals," he said.
Data from the Health Service Executive (HSE) was also released which showed NCHDs were working 51 hours a week at the end of last year - down from 60 hours in 2009 and 54 in 2012.
Health chiefs also said that 400 additional junior doctors have been hired in the last two years in a bid to ease the pressure on the lower medical ranks.
And they said 95% of the shifts junior doctors complete are now less than 24 hours.