Edwin Poots's defeat on blood donation is not the first time he has faced questions over his role as health minister.
The DUP member has also been criticised for plans to take a legal fight against the extension of adoption rights to northern Ireland's gay and unmarried couples to the UK's highest court. In October last year the ban was held to discriminate against those in civil partnerships and to breach their human rights.
The issue prompted campaigners to set up an online petition calling for the minister to resign or be removed from his post. Following last week's High Court ruling one man has spent £20 registering the website domain name HasEdwinPootsResignedYet.com. In May Mr Poots apologised "unreservedly" at Stormont for stress suffered by residents of care homes planned for closure.
His apology followed a public outcry over plans to close 18 NHS care homes, affecting 307 residents.
The minister told health trusts to drop their care homes policy, saying the closures would instead be handled by the Health and Social Care Board. In January last year Mr Poots faced criticism over a whistleblower probe into a child abuse scandal.
The Irish News revealed the allegations of abuse at Lissue House Hospital in Lisburn, Co Antrim, and Forster Green Hospital in south Belfast in the 1980s and early 1990s.
More than 200 health-care staff received "questionnaires" from the Health and Social Care Board to establish who had leaked reports exposing the revelations.
n scandal: Lissue House Hospital was at the centre of child abuse allegations