Health workers in Derry are to join other NHS workers across the North in a 12-hour strike from 9.00am today.
Ambulance crews will join the stoppage from noon.
It is the third stoppage by members of the GMB and Unite unions in a row over pay.
In a statement, a spokesperson for Northern Ireland's Department of Health said contingency arrangements were in place to ensure that patient safety was not compromised.
Unite's health officer, Kevin McAdam, said unions would increase the industrial action in March if no settlement was reached.
Subscribe or register today to discover more from DonegalLive.ie
Buy the e-paper of the Donegal Democrat, Donegal People's Press, Donegal Post and Inish Times here for instant access to Donegal's premier news titles.
Keep up with the latest news from Donegal with our daily newsletter featuring the most important stories of the day delivered to your inbox every evening at 5pm.