People are being urged not to ask their doctor for antibiotics as part of a new campaign aimed at tackling growing resistance to the drugs.
An estimated 5,000 people die every year in England due to the fact antibiotics no longer work for some infections, according to Public Health England (PHE), which has launched the Keep Antibiotics Working campaign.
England's Chief Medical Officer, Professor Dame Sally Davies, has warned of a "post-antibiotic apocalypse", where antibiotics no longer work for serious infections.
The Government wants to see a further drop in antibiotic prescribing by GPs with the aim of combating the threat from resistance.
Antimicrobial resistance (AMR) occurs when bacteria changes in such a way that the medication used to treat them - in this case antibiotics - becomes ineffective.
The new campaign tells people to always trust their doctor, nurse or pharmacist on when to take antibiotics. It says that if they are prescribed, they should be taken as directed and never saved for later or shared with others.
Antibiotics do not work on many common conditions, such as colds, flu, earache, sore throats and some chest infections.
However, people should see their GP if they have prolonged symptoms and develop other issues such as a sickness, a very high temperature or shortness of breath.
Dame Sally said: "Without effective antibiotics, minor infections could become deadly and many medical advances could be at risk - surgery, chemotherapy and Caesareans could become simply too dangerous.
"But reducing inappropriate use of antibiotics can help us stay ahead of superbugs.
"The public has a critical role to play and can help by taking collective action.
"I welcome the launch of the Keep Antibiotics Working campaign, and remember that antibiotics are not always needed so always take your doctor's advice."
Melissa Mead, whose son William died from sepsis due to a chest infection that could have been treated with antibiotics, said she backed the campaign but warned there should be "less of a taboo" over prescribing antibiotics when needed.
William, from Cornwall, had been ill for six to eight weeks before he died and had been seen by GPs six times before his death.
The doctors failed to diagnose a chest infection and eventual pneumonia which led to the sepsis that killed him. A report into his death said there was pressure on GPs to reduce antibiotic prescribing.
Mrs Mead said: "Earlier intervention with antibiotics would have saved William's life. It was clinically evident he needed them."
Professor Paul Cosford, medical director at PHE, said: "Antibiotic resistance is not a distant threat, but is in fact one of the most dangerous global crises facing the modern world today.
"Taking antibiotics when you don't need them puts you and your family at risk of developing infections which in turn cannot be easily treated with antibiotics.
"Without urgent action from all of us, common infections, minor injuries and routine operations will become much riskier."
Experts have suggested that, in just over 30 years, antibiotic resistance will kill more people globally than cancer and diabetes combined.
Health Minister Steve Brine said: "This Government is firmly committed to combating drug-resistant infections and refuses to allow modern medicine to grind to a halt - simple steps can make a huge difference."