A man living in Health Service Executive-supported accommodation died on a weekend when no staff were available, an inquest has heard.

John O'Hanrahan, 37, of Castlecurragh Vale, Blanchardstown, Dublin died on 8 February 2015.

His family were notified of his death the following day by the man's psychiatrist, Dublin District Coroner's Court heard.

Hostel worker Denise Campbell carried out supervisory and housekeeping duties at the five-bedroom house in Blanchardstown.

There were four residents living there at the time, she said.

The deceased man's father, Noel O'Hanrahan, told Coroner Dr Myra Cullinane he thought there was no staff at the facility on the day of his son's death.

Ms Campbell confirmed there was no staff available.

"There was no weekend staff available to work that weekend," she said. "It happens every now and then."

Ms Campbell said she arrived at work on Monday 9 February at 8am.

She called the residents to get up for work or attend their individual activities.

When she got no response from Mr O'Hanrahan, she entered his room; he was unresponsive and his body was cold, she said.

Mr O’Hanrahan had suffered a period of instability in early January 2014 when he stopped taking his medication, the court heard.

However, he was doing well at the house and was described as being in good form prior to his death.

Mr O’Hanrahan had gone to his mother's house on the Saturday, his father told the court. He returned to the house on Saturday night.

He had a number of medications in his system at the time of his death, including xanax, valium and the anti-psychotic drug clozapine.

A post-mortem examination report found he died due to the combined central nervous system depressive effects of xanax, diazepam and clozapine, according to Pathologist Dr Eamonn Leen.

A toxicology report showed he also had zopiclone, a sleeping pill, and morphine in his system at the time of his death.

None of the substances were present in toxic levels but the combined effect is "extremely sedating", the coroner said.

"The depression of the central nervous system deprives you of the stimulus to breathe, you enter into a deep coma from which you do not recover," Dr Cullinane said.

Returning a verdict of death by misadventure, the coroner offered her condolences to the family.

"Clearly he had difficulties but he was very well loved and supported and he was getting some stability back into his life," Dr Cullinane said.