The latest figures from Public Health England found that 5.6 million people a year are being prescribed an opiate-based medicine in England alone, with at least 25 per cent using the drugs for three months or more.

The medication is usually used for pain relief after operations, patients suffering musculoskeletal disorders or cancer or those needing end of life care.

But they can result in addiction, dependency and an increased risk of falls and early death, and the Royal College of Anaesthetists says there is little evidence that they help with long-term chronic pain.

In April, the National Institute for Health and Care Excellence issued guidance suggesting they should not be given to people with long-term pain.

According to the Priory Clinic, 50 million prescriptions were written for opioids last year – an increase of 35 per cent in the last decade. During that time, overdoses have increased by 87 per cent to 12,000 and deaths by 41 per cent to 4,000 a year.

Of the 115,000 prescriptions written every day, five result in a death. The researchers said that the rise of “physician prescribing habits”, rather than the needs of patients, accounted for the increase in opioid prescribing.

The study involved a feedback intervention over a year in which GPs were given two-monthly updates on the number of people at their practice being prescribed opioids.

Doctors were reminded of the need to “initiate opioids with caution” and to review whether patients should continue to receive opioids when there is no benefit.  

Dr Tracey Farragher, an epidemiologist at the University of Manchester and analyst on the study, said: “This study is a great example of how health records can improve patient care by providing up-to-date information to doctors about how many of their patients are being prescribed opioids.”

The research was published in the journal Plos Medicine.