Normally patients in need of medical attention are visited by Public Health Nurses at their homes.
But now only essential calls are being answered as nurses are ferried to many rural areas across the county by members of the Civil Defence, Nowdoc cars and the Mountain Rescue vehicles.
Patients are being contacted by phone where a nurse cannot call to their home and a later appointment is being made.
The HSE is also asking family members to visit elderly people to make sure they have everything from adequate medication to blankets.
A number of day centres and meals on wheels services have also been forced to cancel or operate a very reduced service because of the treacherous road conditions as a result of the freezing conditions.
A spokesman for the HSE asked people to be patient as resources are stretched at present.
Letterkenny General Hospital reported a busy couple of days with a number of fractures as a result of falls.
“Thankfully a lot of people are heeding the advice and staying at home and that has greatly reduced pressure on our services.
“We would ask relatives of elderly people to visit them as often as they can and to ensure that they have everything they need from medication to fuel.
“The community health service is stretched at present and simply cannot physically get to many people – especially those living in outlining areas across Co Donegal,” he said.