The government rejected advice from its expert advisers on swine flu, who said there was no need for the widespread use of Tamiflu and suggested that the public should simply be told to take paracetamol.

An independent panel set up by the Department of Health warned ministers that plans to make the stockpiled drug widely available could do more harm than good, by helping the flu virus to develop resistance to the drug.

But ministers pressed ahead with a policy of mass prescription, fearing the public would not tolerate being told that the millions of doses of Tamiflu held by the state could not be used during a pandemic, one of the committee members has told the Guardian.

"It was felt ... it would simply be unacceptable to the UK population to tell them we had a huge stockpile of drugs but they were not going to be made available," Professor Robert Dingwall, a member of the Committee on Ethical Aspects of Pandemic Influenza, said.

Today one of the country's foremost flu experts called for the national helpline to be shut down to stop hundreds of thousands of doses of Tamiflu going out in an unregulated way, which could render it useless when a more dominant strain returns in the autumn.

As it became clear that the current outbreak only had mild symptoms, the committee recommended that antivirals should only be given to those in high risk categories, like pregnant women or people with existing respiratory illnesses. It suggested the government explain to people that they would not be given medicine they did not need and should use off-the- shelf flu treatments.

"There were discussions within the Health Protection Authority and the Department of Health, once it became clear that swine flu was a relatively mild infection, about whether to reserve antivirals for high-risk groups and to advise the general population to treat themselves with paracetamol or ibuprofen," said Dingwall, director of the Institute for Science and Society at Nottingham University.

"Some people wanted to take a long-term view of the risk of resistance developing and to seek to preserve the effectiveness of antivirals for the next pandemic, which may be more severe."

Last month, the government launched the national pandemic flu service which authorised more than 511,000 courses of Tamiflu and Relenza treatment during its first fortnight in operation.

Oxford University researchers have warned that antivirals are not a "magic bullet" against flu, and that resistance to the drug could develop, making it useless to fight any future and potentially more serious pandemic flu strain.

The concern was seconded by flu expert Hugh Pennington, emeritus professor at Aberdeen University, who called for the national flu line to be shut down.

"I am concerned about the vast amount of Tamiflu that is going out almost unregulated," he told the Guardian. "We are increasing the possibility that the flu will become resistant sooner or later. At the moment there is no desperate need for Tamiflu. We should be reconsidering its issue, rather than encouraging its use.

"I think we should stop the national pandemic flu service. It was put there for an outbreak of far higher mortality than we have. If you get a resistant strain that becomes dominant in the autumn, Tamiflu will then be useless."

A senior government adviser, Prof Peter Openshaw, said the government was told during the early stages of the current outbreak of the "significant side effects" that Tamiflu was causing in some people.

"I think there was, in some quarters, a slight over-optimism about the acceptability of prophylactic medication and its effectiveness," said Openshaw, a member of the Scientific Advisory Group for Emergencies. "Maybe some of the less clinical scientific advisers perhaps slightly over-inflated expectations of the ease and efficiency of antiviral treatment. Many of us who do clinical work and are clinically trained had a bit more of a jaundiced view of how things may turn out."

Openshaw said antivirals were effective only if used within 36 to 48 hours of symptoms developing. "If the treatment is delayed they are relatively ineffective.

"On the other hand, we do have this large stockpile available and I think there is an advantage in trying to treat cases early, in order to reduce the severity and the number of patients who end up needing hospital care."

Such a policy could "blunt" a spike of cases, reducing pressure on health resources, he said.

The pandemic ethical committee was set up at the request of Sir Liam Donaldson, the chief medical officer, to assist planners and policy makers with ethical aspects of decisions they face in a pandemic, such as how to allocate scarce drugs when many people are sick.

At its last meeting in May, when it was already becoming clear that the current H1N1 strain was causing a relatively mild disease in most people, the committee discussed the government's antiviral strategy.

Members feared that the widespread use of antivirals in the current outbreak was incompatible with the principle of minimising harm, minutes from the meeting show. The current outbreak did not alter the risk of a more serious flu pandemic developing in the future. There would be ethical concerns if the blanket use of antivirals compromised their effectiveness in the future.

Members said it was important to use antivirals in the most appropriate way, not just because the government had a stockpile of the drugs. The committee called on the government to explain to the public that they were no cure for flu.

The committee concluded that it would be appropriate to offer antivirals as treatment only for those in risk groups, or with underlying conditions.

In a statement, the Department of Health said: "Protecting the public is the prime concern of our strategy, which has been shaped by advice from the most eminent specialists from the beginning.

"There is still doubt about how swine flu affects people – a safety-first approach is the best approach. This means offering antivirals when required. However, we will keep this policy under review as we learn more about the virus and its effects. This is in line with the views of both the Committee on Ethical Aspects of Pandemic Influenza and of the Scientific Advisory Group for Emergencies.