Antibiotics are used to treat or prevent some types of bacterial infection. They work by killing bacteria or preventing them from spreading. But they do not work for everything.
Many mild bacterial infections get better on their own without using antibiotics.
Antibiotics do not work for viral infections such as colds and flu, and most coughs and sore throats.
Antibiotics are no longer routinely used to treat:
ear infections in children
When it comes to antibiotics, take your doctor's advice on whether you need them or not. Antibiotic resistance is a big problem – taking antibiotics when you do not need them can mean they will not work for you in the future.
Antibiotics may be used to treat bacterial infections that:
People at a high risk of infection may also be given antibiotics as a precaution, known as antibiotic prophylaxis.
Read more about when antibiotics are used and why they are not routinely used to treat infections.
Take antibiotics as directed on the packet or the patient information leaflet that comes with the medicine, or as instructed by your GP or pharmacist.
Antibiotics can come as:
If you forget to take a dose of your antibiotics, take that dose as soon as you remember and then continue to take your course of antibiotics as normal.
But if it's almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.
There's an increased risk of side effects if you take 2 doses closer together than recommended.
Accidentally taking 1 extra dose of your antibiotic is unlikely to cause you any serious harm.
But it will increase your chances of getting side effects, such as pain in your stomach, diarrhoea, and feeling or being sick.
If you accidentally take more than 1 extra dose of your antibiotic, are worried or you get severe side effects, speak to your GP or call NHS 111 as soon as possible.
As with any medicine, antibiotics can cause side effects. Most antibiotics do not cause problems if they're used properly and serious side effects are rare.
The common side effects include:
Some people may have an allergic reaction to antibiotics, especially penicillin and a type called cephalosporins. In very rare cases, this can lead to a serious allergic reaction (anaphylaxis), which is a medical emergency.
Read more about the side effects of antibiotics.
Some antibiotics are not suitable for people with certain medical problems, or women who are pregnant or breastfeeding. Only ever take antibiotics prescribed for you – never "borrow" them from a friend or family member.
Some antibiotics do not mix well with other medicines, such as the contraceptive pill and alcohol.
Read the information leaflet that comes with your medicine carefully and discuss any concerns with your pharmacist or GP.
Read more about:
There are hundreds of different types of antibiotics, but most of them can be classified into 6 groups.
Page last reviewed: Mon May 2022 Next review due: Mon May 2022