For the second time in five days, the Mid-Western Regional Hospital in Limerick has appealed to people not to attend its emergency department because of overcrowding.
There were 38 people on trolleys at the hospital this morning, the highest in the country.
Beaumont Hospital in Dublin had 37, and both Connolly Hospital in Blanchardstown and Our Lady of Lourdes Hospital in Drogheda had 27 patients waiting on trolleys for beds.
Hospital authorities in Limerick say they have not been able to explain why the department has been so busy in recent days.
They say no particular sickness or illness is evident as being the cause.
Members of the public have been asked not to attend the emergency department in Limerick unless it is absolutely necessary.
They are asked to attend their GPs instead, who have also been informed of the situation at the hospital.