Printing the cost of drugs on their packaging is one of Jeremy Hunt’s latest ideas for helping the health service save money.

Arguing that patients need to use NHS resources responsibly, the health secretary said that ministers “intend to publish the indicative medicine costs to the NHS on the packs of all medicines costing more than £20.” Alongside the price, the phrase “funded by the UK taxpayer” will be printed. “This will not just reduce waste by reminding people of the cost of medicine, but also improve patient care by boosting adherence to drug regimes,” he said.

This is not a new idea, neither is it a good one.

As the BMA pointed out when the King’s Fund suggested the idea in 2011, the high cost of some drugs would mean that such a move might deter some patients, such as the elderly, from taking their medicines.

In 2010, researchers from the University of London’s School of Pharmacy pointed out that printing prices on drug packaging may not be possible under European law and that most experts were “more inclined to think that it would cause more problems than it would solve.”

The organisation Pharmacy Voice has also criticised Hunt’s latest proposals. “Although this may seem superficially attractive, there is little evidence that it will have the desired effect, and there may be unintended negative consequences,” it says. “The value of a medicine to an individual is about a good deal more than the price,” it adds.

In any case, the move might not actually save money. To do so, any reduced use of medicines would have to be appropriate, otherwise the health service would face additional costs from patients not taking their medicines as prescribed. The cost saving in reduced medicines use would also have to be greater than the increased salary costs of healthcare workers spending time explaining pharmaceutical pricing, and the importance of treatment compliance, with patients. Savings would also have to offset the cost to the NHS of pharmacists having to work out and print the prices on drug packaging.

Only pricing those over £20 may achieve some of Hunt’s aims in creating a greater perceived value to patients of the medicines they receive. But it clouds the argument over cost transparency when so many medicines are far cheaper than the NHS prescription charge that patients are asked to pay.

The move also throws up all sorts of questions. It is not clear what price would be printed. Costs to the NHS vary across primary and secondary care, and from week to week. For any generic medicines included in the Category M section of the Drug Tariff, the effective cost to the NHS is not determined until weeks or months after the drugs have been dispensed.

It is also not clear why medicines been selected for this special treatment. The UK uses the money it spends on pharmaceuticals, particularly those dispensed in primary care, extremely efficiently.

Ambulances could just as easily have the cost to the taxpayer of each call out plastered on their sides, and all NHS staff could have the hourly cost to the taxpayer of their salaries printed alongside their name badges. But neither of those possibilities is being put forward by the health secretary.

Aside from the lack of evidence that the measure would achieve its desired aims, and the difficulties in applying it in practice, I am uncomfortable about the idea in principle. We should accept that patients are generally trustworthy and have not, by and large, willingly chosen to have illnesses that need expensive treatment.

A patient whose medicine is priced at more than £20 does not need to know the cost to the NHS more than a patient whose condition is less expensive for the NHS. The NHS does not put prices on its patients in that way and we should not want to shame them by telling them how much they are costing taxpayers.

Tom Moberly is the editor of BMJ Careers. Follow Tom on Twitter @tommoberly.