Symptoms of food poisoning 

The length of time it takes for the symptoms of food poisoning to develop will vary depending on the type of bacteria involved and how much contaminated food is eaten.

The incubation period (the time between eating contaminated food and the onset of symptoms) can be as short as a few hours or as long as several weeks.

Read more about the causes of food poisoning and the differences in incubation periods.

The most common symptoms of food poisoning are:

Vomiting usually only lasts for a day or so, but it can sometimes last longer. Diarrhoea will often last for a few days, although you may continue to have an upset stomach for about a week or so.

Other symptoms of food poisoning include:

  • stomach cramps
  • abdominal pain 
  • loss of appetite
  • a high temperature of 38°C (100.4°F) or above
  • muscle pain
  • chills

Most people make a full recovery 1-2 days after the onset of symptoms.

When to seek medical advice

Most cases of food poisoning do not require medical treatment. However, you should seek medical advice if you have any of the following signs or symptoms:

  • vomiting that lasts more than two days
  • you are unable to keep liquids down for more than a day
  • diarrhoea that lasts for more than three days
  • blood in your vomit
  • blood in your stools
  • seizures (fits)
  • changes in your mental state, such as confusion
  • double vision 
  • slurred speech
  • signs of severe dehydration, such as a dry mouth, sunken eyes and an inability to pass urine, or passing small amounts of dark, strong-smelling urine

Pregnancy

Always contact your GP if you get food poisoning during pregnancy. Extra precautions may be needed. 


Reporting food poisoning

If you think your food poisoning has been caused by a restaurant or other food-related business, report it to your local environmental health department.

Environmental health officers will investigate and, if necessary, ensure that the business involved improves its standards of hygiene to prevent it happening again.

The Food Standards Agency provides further details about reporting poor hygiene standards in a food outlet.

Page last reviewed: 27/03/2013

Next review due: 27/03/2015