The Irish Nurses and Midwives Organisation have asked Letterkenny University Hospital to review their security after staff were approached by anti-vaccination protestors.
Members of staff at the hospital contacted the INMO after the incidents in the grounds of the hospital in recent days.
It is understood that staff were approached by inside and outside the hospital by protesters.
Staff were shouted at and followed in at least three incidents outside the hospital.
Staff were also filmed inside the hospital while carrying out their duties.
It follows a high-profile incident in which a Covid-19 patient was taken from the hospital against medical advice of doctors.
Mr Joe McCarron was taken out of the hospital on Tuesday last but rushed back in on Thursday and is now fighting for his life.
Mr McCarron’s family have now apologised for their actions and described the behaviour of those who accompanied Mr McCarron as “reckless.”
A spokesman for the INMO said they could not comment on individual cases of staff members.
However, the spokesman confirmed that a review of security at the Letterkenny facility has been requested.
He said “Busy clinical staff cannot be expected to deal with this kind of behaviour or be subjected to this kind of abuse.
“Management need to protect staff and patients. We have requested an immediate review of security to prevent patient endangerment.
“The HSE and hospital management across the country must have preventative plans in place.”
A Garda spokesman confirmed they responded to two incidents at the hospital in recent days following disturbances there.
Asked if Garda patrol around the hospital had increased the spokesman added “An Garda Síochána does not comment on operational matters.
“Local Garda management have implemented a policing plan to ensure any incidents that occur in this district are treated as urgent.”