AMBULANCE chiefs for Hartlepool and East Durham referred themselves to health watchdogs after it was discovered patients had been given out of date drugs.
The North East Ambulance Service uncovered the blunder during an internal audit.
It found that medicines past their use by dates, including morphine had been administered by paramedics to patients.
The ambulance trust has referred itself to the care watchdog the Care Quality Commission, and health services regulator Monitor.
But it has stressed people were not put at risk due to the error.
A spokesman for the ambulance service said: “During a routine audit by NEAS, a number of out of date controlled drugs were found to have been administered to patients. In total 75 doses had been administered by 26 paramedics.
“The specific medicines were Morphine, Oramorph oral suspension and Diazamuls.
“No patients were put at risk due to the drugs being out of date.
“The Care Quality Commission and Monitor – a health watchdog – are aware of the situation, along with our commissioners.
“Since the error came to light we have tightened-up our controlled medicines checking procedures.”
The Care Quality Commission said it is satisfied the trust did everything it could on dealing with the blunder.
But it says it will keep an eye on the issue during follow-up inspections over outstanding concerns.
In May, the commission found shortfalls in the trust’s management of medicines and was given a formal warning.
A spokesman for the watchdog said: “We can confirm we were alerted to this matter by the North East Ambulance Service NHS Foundation Trust in April.
“We asked the trust for an action plan and after reviewing that plan we were reassured that the actions taken by the trust to mitigate the risk were robust.”
The news follows a series complaints about the ambulance service including patients with painful injuries waiting hours for ambulances.
The issue has been raised in Parliament by Hartlepool and Easington MPs Iain Wright and Grahame Morris.