Nurses and midwives have confirmed they will hold the first in a series of strikes on the last Wednesday of this month.
If a row over pay and conditions isn't solved, there'll be more 24 hour stoppages on February 5th, 7th, 12th, 13th and 14th.
Workers say they also want to fix problems with staff recruitment and retention, and conditions for patients.
They say the HSE is not able to hire enough nurses and midwives, because wages are here are too low and working conditions are better in other countries.
The strike will see INMO members withdraw their labour for 24 hours, providing only lifesaving care and emergency response teams.
The Government has repeatedly ruled out granting the 12% pay rise sought by nurses and says there would be knock on claims across the public sector.
The number of staff nurses fell by 1,754 (6%) between 2008 and 2018.
This would be only the second national strike ever for members of the Irish Nurses and Midwives Organisation.
INMO General Secretary Phil Ní Sheaghdha said going on strike is "the last thing a nurse or midwife wants to do", but said staff "are not able give patients the care they deserve under these conditions".
INMO President Martina Harkin-Kelly said "Ireland’s patients deserve better than this understaffed health service".
"The public health service no longer pays a competitive wage, so we can no longer get the necessary number of nurses and midwives", she said.
The Health Minister believes the planned action could be avoided.
Simon Harris will invite the INMO to talks next week, as he says there is "clear" and "essential" need for engagement.