A staff shortage led to 50 sex attack victims enduring lengthy journeys to be treated and forensically examined last year.
One woman had to travel in an unmarked garda car to the Mullingar sex assault unit because the 24/7 centre at the Rotunda Hospital in Dublin was closed, a report has revealed.
"I went to the station at 4am and didn't get seen until 3pm in Mullingar. They said there were two other cases in Mullingar before my case," she said.
Patients who cannot access the service locally face a journey of several hours, having been unable to shower or eat and drink anything.
They can then spend three to five hours being treated and examined.
The harrowing accounts emerged in a Department of Health review of the six sexual assault treatment units that was published by Health Minister Simon Harris yesterday.
The extended journeys were found to have a "direct impact" on the level of trauma experienced by patients.
This is particularly the case for those who have not been referred by gardai.
Mr Harris said that among the immediate steps being introduced are an investment of €500,000 and the appointment of more nurses and doctors who are trained in forensic examination.
The report found that the units in Dublin, Galway, Mull- ingar, Cork, Letterkenny and Waterford treated nearly 1,000 patients last year.
Some former patients spoke of feeling "safe" in the unit and another said they "could not fault it".
However, others found the surroundings cold, clinical and unwelcome.
One said they were left on their own with nobody checking on them.
Current and former staff who were interviewed complained about levels of pay and allowances as well as being unsupported in their work, or feeling like the "poor relation of the hospital".
The report points to serious under-investment in the service.
A small number of staff are said to carry the weight of the "out of hours" support.
One in 10 patients are men and half are aged under 25.
A high proportion of victims tend to have an intellectual disability.
A significant number also comes from state settings such as prisons, residential care homes and nursing homes. Some are homeless.
Assaults tend to spike during university freshers' weeks, music festivals, conference events and gigs. Other cases happen at home or in a family.
The report warned that a lack of liaison between services including An Garda Siochana meant some patients needing follow-up support are falling through the cracks.
Mr Harris expressed his concern not only as a minister, but as a citizen.
He said there appeared to be a surge in sex assault cases during public events such as the Leaving Cert results' night.
At the launch of the report, Junior Education Minister Mary Mitchell O'Connor expressed her concern about the "alarming" levels of sexual assault.
The high incidence emerged in a survey by the Union of Students in Ireland.