The HSE is expecting to ramp up the number of coronavirus tests being carried out from today.
A new online system is being rolled out so GPs can order tests for their patients.
Out of hours services were flooded with calls over the weekend.
President of the Irish Medical Organisation, Dr Padraig McGarry, says it means there'll probably be a backlog this morning.
"Patients shouldn't be ringing up looking for a test unless they really have clinical symptoms.
"People with respiratory symptoms should ring up and get access through a GP
"However what is much more important is that people with respiratory symptoms should self isolate - that's the most important thing."
