Information for the public

Human and animal bites: do I need antibiotics?

There is a risk of infection from a human or animal bite if it breaks the skin. Signs of infection include redness and swelling, which may feel hot and painful, and a fever. There may be discharge (liquid that leaks from the bite) or an unpleasant smell.

You do not need antibiotics if the bite has not broken the skin. Using antibiotics when they are not needed means they may not work as well in the future. This is a serious health risk, so NICE has written advice about when to offer antibiotics for some common conditions.

However, you will be offered antibiotics if the bite is infected. If there is discharge from an infected bite, your doctor should take a sample to check which bacteria are causing the infection. They may offer you a different antibiotic when the results of these tests come back. Most infected bites get better after 5 to 7 days of antibiotics.

Sometimes you may be offered a short course of antibiotics (for 3 days) to prevent an infection developing. This depends on:

  • what bit you
  • whether the skin is broken or bleeding
  • how deep the bite is or how much damage it has caused.

You may also need antibiotics if you are at risk of a serious infection because of where the bite is on your body, or if you have an underlying health condition.

Your doctor should explain that antibiotics can cause side effects.

Seek medical help if:

  • signs of infection suddenly get worse at any time or you feel very unwell
  • you have not started to feel better 1 to 2 days after you start antibiotics.

You may have to go to hospital if you have signs of a serious illness, such as sepsis, or if the wound is severe.

Making decisions together

Decisions about treatment and care are best when they are made together. Your health professionals should give you clear information, talk with you about your options and listen carefully to your views and concerns.

If you cannot understand the information you are given, tell your health professional.

Read more about making decisions about your care.

Where can I find out more?

The NHS website has more information about:

This organisation can give you advice and support: St John Ambulance, 08700 104950.

NICE is not responsible for the content of this website.

We have also written information on why antibiotics should be used wisely.

We wrote this guideline with health professionals and members of the public. All the decisions are based on the best research available.

ISBN: 978-1-4731-3901-5

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