People in the Northern Sound region have been advised that "long delays are to be expected" at Cavan General Hospital's Emergency Department.
Patients are being told to expect "long delays" due to a "significant increase in attendances" and a "prolonged period of increased activity".
Those with non-emergency needs are asked to seek alternative medical assistance from a GP or pharmacy.
Cavan General Hospital has requested the public's "continued support in hospital avoidance where possible" and has thanked the public for its support.