People are again being urged to stay away from Emergency Departments (EDs) and GP surgeries unless it is urgent, following Storm Ophelia.
Three people lost their lives on Monday in separate incidents during the storm - a woman in her 50s in Waterford, a man in his 30s in Tipperary and a man in is 30s in Louth.
Meanwhile as many as 245,000 homes and businesses remain without power and some 20,000 homes are without water.
Met Eireann's ‘Red' level warning remained in place until 1am last night.
The Minister for Health, Simon Harris thanked everyone working in the health service for what he described as a ‘difficult and challenging' day.
While all outpatient appointments were cancelled yesterday, these are resuming today. People have been advised to attend their appointments as planned unless they hear otherwise. Patients will be contacted if their appointment has been cancelled.
However, Minister Harris warned that there will probably be some delays in appointments and discharges over the coming days.
"We do expect some continued disruption over the coming days, but we can expect a gradual return to normal services and that is now our priority.
"Following the significant disruption today, it is expected that both EDs and GPs will be very busy today, so I would ask if you don't have an appointment and if it's not urgent, please don't attend your GP or hospital," he said.
The Irish Medical Organisation (IMO) also warned that EDs will ‘take some days to work through the backlog of patients built up' as a result of Storm Ophelia.
"Doctors and all healthcare professionals have worked around the clock to ensure that patients who needed attention received it. Though the storm made delivering essential care challenging, hospitals and GP practices were available to provide help and emergency support to patients.
"I want to acknowledge the huge effort which doctors put in across the country and thank the public for their support for doctors and other healthcare professionals during the storm period," commented Dr Padraig McGarry of the IMO.
The Irish Nurses and Midwives Organisation (INMO) also highlighted the commitment of frontline staff during the storm.
"In particular, we acknowledge the commitment to maintain, as far as possible, community/home based services and visits. This will continue but we must all be vigilant and aware of neighbours who normally receive such services and may need extra care and attention at this time," commented INMO general secretary, Liam Doran.