UHG has issued a public appeal as the hospital remains under very significant pressure.
Those attending are being asked to consider where the Emergency Department is the right pathway for their care needs.
The hospital has been under heavy pressure all week, partly due to a peak in flu cases.
It says flu cases rose by almost 40 percent in the two weeks to January 1st, and COVID-19 is circulating at high levels.
As a result, those presenting with non-urgent issues, could face very long waiting times for treatment.
Professor John O’Donnell, Consultant in Emergency Medicine, has this advice on alternatives to visiting the Emergency Department: