If you obtained your citizenship by naturalisation, there are some circumstances in which it can be revoked (taken back from you) such as providing false or misleading information. Section 19 of the Irish Nationality and Citizenship Act, 1956 provides for the revocation of certificates of naturalisation. Information for Section 19 can be found here.
How revocation happens
You will be contacted by the Minister for Justice and Equality if your citizenship is to be revoked. If your citizenship is to be revoked, you may apply for an inquiry into the reasons why.