Investigation into RNSH patient incident

Investigations have been launched into a "distressing" incident in which a man spent 20 hours unconscious in a Sydney hospital toilet cubicle, says NSW Health Minister Jillian Skinner.

The man went to the Royal North Shore Hospital on Monday for a routine appointment in the outpatient clinic, but when he failed to present himself to the clinic staff, he was listed as a "no show", Ms Skinner has been told.

"Royal North Shore Hospital has initiated a major investigation into this case - in particular, how the gentleman remained unnoticed in a toilet cubicle until Tuesday morning after becoming incapacitated," the minister said in a statement.

"This is a distressing case and I extend my sympathy to this gentleman and his family."

The hospital has added checks of public toilets in outpatient areas to its end-of-day shutdown procedures, Mr Skinner said.

The minister has asked RNSH to keep her informed of the investigation progress and any other measure that could prevent a similar incident.