Section 39 workers are demanding pay restoration in line with other health sector employees.
The healthcare workers took a pay cut in 2008 and now want it restored.
They are demonstrating ahead of a day of strike action across the country on the 18th of September.
SIPTU says an agreement between parties was made to ensure pay cuts would begin to be restored by the end of this year but it has not happened yet.
Paul Bell SIPTU Health Division Organiser wants the Health Minister to intervene: "We do not have any confidence at this stage that this matter is going to be resolved unless the Department of Public Expenditure make the call to support funding for these organisations.
"We do understand that compromises have to be made but the business of negotiation normally means that we can reach an end with a compromise.
Barbara Clinton is a care assistant for 28 years with Westin Care in County Mayo.
She says they want justice and parity with public servants working in health agencies.
"We do exactly the same work as Section 38 but we're not recognised even though the linkage has been made but we seem to be second class citizens and we want our money back.
"We've all taken a massive hit and it's time, we want our money back."