Letterkenny General Hospital says the current delays within the Emergency Department are the result of high numbers of people attending with flu related.
A reduced numbers of medical staff available due to a combination of recruitment difficulties and sickness is also adding to the problem.
Letterkenny General Hospital says it is taking all necessary steps to deal with the current surge, which includes the deferral of elective surgery.
People are asked to avoid attending the Emergency Department where possible. People who are attending the Emergency Department are being told they can expect delays.
Hospital management is encouraging the public to keep Emergency Departments for emergencies and would advise people to contact their GP, GP Out of Hours services or Pharmacist in the first instance.
Due to the high number of emergency admissions recently, patients who are due for a planned admission as an inpatient this week should ring Letterkenny General Hospital beforehand to confirm the availability of a bed.