Hospital patients recovering from surgery are being discharged into hostels for homeless people if they have no one to care for them, says the voluntary body, Trust.
Other people end up in hostels because they lose their flats when they are hospitalised, says the organisation in a new booklet.
Trust provides a medical and clothing service for homeless people at Bride Road in Dublin. It is chaired by Prof James McCormick and directed by Ms Alice Leahy.
"It is unfair to expect untrained hostel staff to be able to care for very ill residents," says the booklet. Convalescence beds should be provided for homeless people recovering from illness to ensure they will be better able to cope when they return to hostels or the streets, it says.
It also highlights a need to help homeless people to face up to problems with drink.
"Given that many of the people who are homeless drink to anaesthetise themselves against cold and wet conditions, and the pain of living on the streets, it makes sense to offer them safe accommodation in the first place to help them stop drinking."
Young women who are pregnant, whether they become homeless as a result of their pregnancy or become pregnant when they are homeless, also need special attention, it says.
Trust and Dublin Corporation have launched a one-day training programme on homelessness. The Homeless Experience programme is aimed at voluntary, statutory and community groups working with homeless people, and consists of a training pack supported by a one-day training course. The programme will be offered to groups throughout the State.