An investigation was launched after a Sheffield man took an overdose while waiting for a mental health bed.
Sheffield Health & Social Care NHS Foundation Trust said a man took a 'non-fatal' overdose of prescription drugs as he was waiting for an inpatient bed to manage his risk of self-harm.
NHS bosses have said an internal investigation was launched and steps have been taken to avert this sort of incident in future in a report published by the Sheffield Clinical Commissioning Group.
The incident, which has only come to light in recent weeks, has raised concerns from Sheffield Central MP Paul Blomfield who said the current funding system for mental health was 'putting lives at risk'.
The investigation and the implementation of a subsequent action plan is believed to have taken over a year.
The report said further training has now been provided to staff which includes improving the access to psychological therapies in order to aid early recognition and referral.
Health bosses have written a protocol for the identification, checking and removing of surplus medication. This may now extent to the Sheffield mental health Crisis House.
Reported 'systems weakness of telephone contact' with the Home Treatment Team between 5 & 6pm has now been addressed.
Kevan Taylor, chief executive of Sheffield Health & Social Care NHS Foundation Trust said: “In June 2015 one of our service users had a planned admission scheduled for a medication change. Shortly before the planned admission, the service user took a non-fatal overdose of medication at home.
"We recognised the serious nature of the incident and we have conducted our own thorough internal investigation into the circumstances leading up to and during the incident. A comprehensive action plan was developed and has now been completed. Both the service user and their family were involved in the investigation and the findings and actions have been shared with them.”
Central MP Paul Blomfield said:"By failing to fund mental health services properly, the Government is putting lives at risk. It's a huge problem. One in four of us will face mental health problems at some stage in our lives. But the services aren't there when they're needed. Mental health services need a fair share of an NHS budget that is just too small."
But Health Secretary Jeremy Hunt said: "I am proud that, under this government, 1,400 more people are accessing mental health services every day compared to 2010 and we are investing more in mental health than ever before, with plans for 1 million more people with mental health conditions to access services by 2020. But we recognise that there is more to do so as will proceed with plans to further improve mental health provision."