More than 1.1m people collected the drugs – which can cause side effects such as nausea – after being diagnosed by the National Pandemic Flu Service.

But figures obtained under a freedom of information request show that of 16,560 people swabbed, 1,932 tested positive.

The Patients Association said this raised questions about the system used.

The flu service was launched last July at the height of the pandemic. It was the first time that prescription drugs had been handed out en masse by the NHS without a patient having to consult a doctor.

Instead, people who felt ill were put through an electronic check-list. Those with swine flu symptoms were then given a voucher number to collect anti-viral drugs, which were used to relieve the illness.

The drugs – Relenza and Tamiflu – both caused a number of side-effects, including nausea and, in some cases, vomiting.

Concerns were also voiced that over-use could have led to resistance – many other countries used them much more sparingly.

There was also a debate about how effective the drugs were.

The independent review of the flu strategy, which was published last week, called for a full evaluation of the flu service, admitting it was a controversial issue.

It cost £13.5m to set it up, although the bill for running it until it closed in February this year has never been published because of commercial sensitivity.

Katherine Murphy, of the Patients Association, said the findings suggested the government had “over-reacted”.

“It is always easy to say in hindsight, but we really do need to review this. It is a low number and we have to bear this in mind when thinking about pandemic planning.”

Dr Richard Vautrey, of the British Medical Association’s GPs committee, agreed “lessons must be learned”.

But he added: “It must be remembered the service played a valuable role relieving the pressure on the health service.”

Shadow health secretary Andrew Lansley said he was looking to change the funding system to tackle the issue.

He added: “Unnecessary emergency admissions create a burden on the NHS. We know that what matters most to patients is the outcome they get and their experience of the NHS – not simply how quickly they are seen.”