Patients should be able to pay for drugs which are not available on the NHS and still receive the rest of their treatment free, doctors said yesterday.

At the end of a heated debate, the British Medical Association was accused of voting for a move which would mean the end of a "free" NHS for all patients Doctors stopped short of demanding government action to change the rules immediately. Instead the BMA, which is holding its annual representative meeting in Edinburgh, called for a Royal Commission to review all the evidence.

Patients across the UK who want to pay for a new medicine which is not offered by the NHS can be told they have to get all their treatment privately.

Some doctors believe it is cruel to place desperate patients in this situation, but for others allowing so-called "co-payments" raises the spectre of cancer sufferers lying side-by-side on a ward receiving different types of chemotherapy because one is wealthier than the other. There are fears it will threaten the principle of universal free healthcare.

Orthopaedic surgeon Gordon Matthews, from Buckinghamshire, told the conference he was arguing for co-payments not only as a doctor but as the husband of "a most cherished wife" with end-stage colon cancer.

He said a tax-funded system could not provide limitless funds and it was right that bodies such as the National Institute for Health and Clinical Excellence (Nice) rationed treatments. But he said that it was not ethical to exclude patients from NHS care because they had made a personal decision to spend money on treatment "when they are clinging to their lives".

Dr Stephen Austin, from the BMA consultants' committee, similarly said forcing patients to leave the NHS if they wanted to pay for new drugs was "healthcare rationing in its most brutal and cruel form".

But Dr Jacky Davis, a consultant radiologist and member of the BMA council from London, pleaded with delegates to vote against co-payments. She said: "We have never had patients in adjacent beds receiving different treatments because of their ability to pay."

Dr Kevin O'Kane, from London, claimed the motion was "poisonous". He said: "I see it as a nail in the lid of the NHS coffin."

The final vote reflected the torn nature of the discussion. A total of 62.8% agreed "patients should have the choice to purchase non-health service treatments and medications if they wish and still receive the rest of their treatment and medication on the health service without being forced to pay for all their treatment privately".

But they narrowly rejected a motion saying the government must permit co-payments across the UK, with the poll split 49.8% in favour and 50.2 against.

Instead the creation of the commission, to investigate the potential consequences and report back by next summer, was endorsed by 70.9% to 29.1%.

A series of riders, intended to stop any introduction of co-payments leading to a wider range of NHS charges, was also agreed.

In England, a review of the practice of denying NHS services to those who want to pay for aspects of treatment has been ordered. There have been high-profile cases of patients forced outside the NHS because they wanted a particular drug. Linda O'Boyle, 64, from Essex, paid £11,000 for an eight-week course of a drug called Cetuximab with the hope of prolonging her life, and was then unable to receive care from the heath service.

A Scottish Government spokesperson said: "The Scottish Parliament Public Petitions Committee Report on the availability on the NHS of cancer treatment drugs has recently set out a number of recommendations for the provision of cancer drugs in Scotland.

"The cabinet secretary for health and wellbeing will be considering these carefully and will respond in due course."