There are five dementia patients on the waiting list for residential care in the Western Trust while a brand new £5m facility in Enniskillen lies virtually empty.
Gnangara residential home, which can accommodate 30 people, opened in October but so far only three people have been placed there.
It has emerged one person is currently waiting for a place in a residential home in Enniskillen, while another four are on waiting lists in Omagh and Londonderry.
Tommy Gallagher, the SDLP MLA for Fermanagh/South Tyrone and a member of the Stormont health committee, said it is a “crazy situation”, particularly in light of the current financial pressures facing the health and social services in Northern Ireland.
Mr Gallagher said: “The sums don't add up here. It is costing over £2,000 per week to keep patients suffering from dementia and other complications in hospital when the medical staff would like to see them discharged. And yet the trust isn't able to find placements costing about half of that in settings such as this.”
The home is owned and run by the Fold Housing Association and receives patients through referral from the Western Trust.
It has 29 full-time staff and offers patients accommodation in apartments or bungalows.
Fold Housing Association has said running costs since October had reached £165,000.
However, Health Minister Michael McGimpsey has defended the situation and said more people will be referred to Gnangara over time.
He said: “It will take time for the trust to arrange all the placements. That is part of the future. The £5m is the investment in dementia services in that area and the number of patients will build.”
A spokesman for the Western Health and Social Care Trust said it welcomed the development of the Gnangara facility.
He said the trust was told in late December that Gnangara had received registration from the Regulation and Quality Improvement Authority.
“Following this, the trust has been working with Fold in identifying people suitable for the newly opened facility,” he added.
“Such a process involving discussion with clients and families and ensuring that they are content with the chosen accommodation does take time.
“New accommodation takes time to build occupancy and the trust will continue to work with Fold to use this facility. Another two people are considering availing of the Gnangara facility.”
The spokesman said the budget was “under significant pressure”, the financial environment was “very challenging” and that the trust would continue to prioritise resources to those with the greatest need.