Patients have been urged not to request antibiotics for coughs and colds due to an increasing resistance to treatments in the population.

It is important for antibiotics to be prescribed only when necessary so the drugs are effective when patients actually need them, the Health Protection Agency (HPA) said.

A new leaflet has been designed so patients have a better understanding of common ailments, and the length of time that they last, so they are less likely to demand antibiotics when they visit the doctor.

The leaflet is being launched to coincide with European Antibiotic Awareness Day (EAAD) on Sunday - which aims to highlight the risks associated with the inappropriate use of the drugs.

"A lot of people with coughs, colds and flu still visit the doctor expecting to be given antibiotics for their treatment and it can be difficult for the doctor to refuse," said Dr Cliodna McNulty, the HPA's lead on EAAD.

"This expectation puts a lot of pressure on the doctor to prescribe antibiotics which is often not necessary and causes increased antimicrobial resistance in the long run.

"Bacteria will always adapt to try and survive the effects of the antibiotic and we have seen that the problem of resistance is growing.

"GP patients who have had antibiotics in the last six months are twice as likely to have an infection with resistant bacteria.

"This is why it is very important that we preserve the antibiotics that we have by not prescribing them where they are not necessary so that they are effective when we really do need them."

The Royal College of General Practitioners (RCGP) helped to develop the patient leaflet as well as additional guidance for GPs.

Dr Michael Moore, RCGP clinical champion for antimicrobial stewardship, added: "The toolkit is aimed at working GPs to give them the means to assess their current practice and to focus on ways to reduce antibiotic prescribing in situations where the evidence shows they are of little or no benefit."

The Department of Health's Chief Medical Officer, Professor Dame Sally Davies, said antibiotic resistance is one of the greatest threats to modern health.

She said: "Antibiotics are losing their effectiveness at a rate that is both alarming and irreversible - similar to global warming.

"I urge patients and prescribers to think about the drugs they are requesting and dispensing.

"Bacteria are adapting and finding ways to survive the effects of antibiotics, ultimately becoming resistant so they no longer work. And the more you use an antibiotic, the more bacteria become resistant to it."