The government will examine claims the NHS was slow to take a "dangerous" automatic syringe out of service.

It follows a whistleblower's warning, reported in the Sunday Times, that the devices could have caused widespread deaths among elderly patients.

The syringes, for powerful painkillers, were permitted to be used until 2015.

Heath Secretary Jeremy Hunt said there were questions over how quickly the NHS reacted "when we knew these syringes were dangerous".

NHS officials issued warnings of the risk of fatalities from user error in the 1990s but the devices continued to be permitted by the NHS until three years ago.

Doctors were concerned that confusing two models of the infusion pumps could lead to a day's dose of drugs being delivered in one hour.

Mr Hunt said: "We need to be absolutely certain that the NHS does react as quickly as possible when you have suggestions a piece of equipment is not safe.

"Urgent guidance was sent out in 2010 and they were finally removed from use in 2015 but we will look at whether that was as quick as it should have been."

Last week the government inquiry into hundreds of deaths at the Gosport War Memorial Hospital found more than 450 patients died after being given powerful painkillers inappropriately.

Speaking to the Sunday Times, the whistleblower said the decision makers on the inquiry panel had "ignored" evidence that the devices caused fatalities because they were worried about a national scandal.

The newspaper claims the syringes were also linked to overdose-related deaths in Wales, South Yorkshire, North Yorkshire, Derbyshire, Devon, Cornwall and the Isles of Scilly.

"Anyone who has lost their granny over the past 30 years when opiates were administered by this equipment will be asking themselves, 'Is that what killed Granny?'," the whistleblower told the paper.

Mr Hunt said claims of a cover-up had been "categorically denied" by the independent panel, who had a "free hand", adding "if they thought there was an issue with the syringe drivers I know they would have said so".

Media playback is unsupported on your device Media caption Hundreds of lives were cut short due to prescribed opioids at Gosport War Memorial Hospital

What were the syringe warnings?

The syringe drivers, called Graseby MS26 and Graseby MS16A, were loaded with capsules and programmed to release drugs into a patient's bloodstream over an extended period

They delivered drugs at different rates - MS26 delivered in mm per 24 hours, MS16A delivered in mm per hour

Cases emerged of the drivers being confused, causing dangerous over-infusion of drugs

The NHS's Purchasing and Supply Agency (PSA) said the devices appeared "very similar aside from colour"

Hazard notices were issued by the Medicines and Healthcare products Regulatory Agency (MHRA) to ensure NHS staff knew the difference between the models

In 1994, the NHS in Scotland issued a hazard notice warning of the risk of death due to confusion between the two models causing drugs to be delivered at the incorrect rate.

Australia and New Zealand had programmes in the late 2000s to remove the devices from use.

A 2008 paper by the NHS's Purchasing and Supply Agency (PSA), which closed in 2010, said the devices were an "essential component of palliative care".

An estimated 40,000 devices - a quarter of the worldwide total - were in the UK, the majority in primary care.

The syringes were briefly mentioned in the report released on Wednesday looking into the deaths at Gosport War Memorial Hospital.

The report said: "The panel has considered issues concerned with the particular syringe drivers, known by their tradename of Graseby, and is aware of the hazard notices which applied.

"The panel's analysis does not rest upon any issue relating to these notices."

A Department of Health and Social Care spokesman said: "While there is a range of statutory requirements to monitor and improve safe management and use of controlled drugs, we would not hesitate to take further action to improve safety."