The Psychiatric Nurses Association (PNA) is calling for a complete review of the Vision for Change policy on mental health.
It also wants the closure of acute beds to be stopped until such a review has been completed.
Speaking on RTÉ's News at One, PNA General Secretary Des Kavanagh said he is extremely worried about people who have taken their own lives following, what the PNA describes as, premature discharge from care or refusal of admission to acute psychiatric care.
He said the Carlow, Kilkenny and South Tipperary regions are highlighted by the Health Service Executive as being the most accurate reflection of the Vision for Change policies recommendations.
If this is the case, he said, it raised serious concern about how they are being implemented.
Mr Kavanagh said that on some occasions, despite the best efforts of all staff and families, some people will take their own lives.
However, he said, when the numbers of suicides have reached the levels that they now have, his members have to cry stop and alarm the community, politicians and HSE management that they cannot stand over what is happening.