Men who have sex with men will no longer have to wait four months before giving blood, as changes to who can donate blood come into effect today.
Instead, individual assessments will now be made.
The medical and scientific director at the Irish Blood Transfusion Service has said today is a great day, as "donations become more inclusive without compromising patient safety".
Dr Tor Hervig said there are 75,000 blood donors in Ireland, but more are needed in order to secure blood supply for patients.
He said Ireland is just one year behind the United Kingdom in changing the criteria.
Rules so far have been very good for patient safety, he said, but in a modern society, it would be expected that the criteria are based on an individual and not a group.
"We are number ten in Europe implementing such regulations, and even in these other countries, the other nine countries, the rules are different," he said.
"So, I don't think we are late, I think we're just on time."
Dr Hervig said it remains to be seen if a lifelong ban should remain for those blood donors who have had gonorrhea because it is a curable disease.
