Exams and Tests

Most food poisoning is mild and passes in a few days, so most people don't go to a doctor for a diagnosis. You can often diagnose food poisoning yourself if others who ate the same food as you also become ill.

If you do go to your doctor, he or she will make the diagnosis based on your symptoms, a physical exam, and your medical history. Your doctor will ask where you have been eating and whether anyone who ate the same food has the same symptoms.

Sometimes the following tests are done.

• A stool culture may be done if your doctor suspects that you have eaten contaminated food, your symptoms are severe, or the diagnosis is uncertain.
• Blood tests may be done to help find out whether the food poisoning is caused by bacteria or to rule out other causes. A complete blood count and a chemistry screen can help show whether you are severely ill or dehydrated.
• If you are pregnant or have an impaired immune system and have been exposed to toxoplasmosis, you may need a toxoplasmosis test. For more information, see the topic Toxoplasmosis During Pregnancy.

Your doctor may need to report your condition to the health department. This is done to help the government track the condition and identify possible outbreaks.

Treatment Overview

In most cases, the diarrhea and other symptoms of food poisoning go away in 2 to 3 days, and you don't need treatment. It may be longer than 2 to 3 days until you feel normal again.

All you have to do is manage symptoms, especially diarrhea, and avoid complications until the illness passes. In most cases, dehydration caused by diarrhea is the main complication. To learn how to care for yourself at home, see Home Treatment.

The goal of treatment is to replace fluids and electrolytes lost through vomiting and diarrhea. If dehydration is severe and can't be managed at home, you may need treatment in the hospital, where fluids and electrolytes may be given to you by inserting a needle into your vein (intravenously).

Medicines that stop diarrhea (such as Imodium) can help with your symptoms. But these medicines shouldn't be used in children or in people with a high fever or bloody diarrhea. Antibiotics are rarely used and only for certain types of food poisoning or in severe cases. Pregnant women with listeriosis or toxoplasmosis may receive antibiotics.

Extra precautions should be taken to prevent dehydration in children. To learn more about treating dehydration in children, see Home Treatment.

For more information on treating diarrhea or dehydration, see the topic:

• Diarrhea, Age 11 and Younger
• Diarrhea, Age 12 and Older
• Dehydration

And for more information on treatment for specific organisms, see Cause.

Botulism, E. coli infection, and infection during pregnancy

For botulism and some cases of E. coli poisoning, immediate and intensive medical care is usually needed.

For more information, see:

• Botulism.
• E. Coli Infection.

Pregnant women should always consult their doctors if they think they may have food poisoning, because the infection can be passed on to the fetus.

Toxoplasmosis and listeriosis can also harm your baby. If you are diagnosed with either of these conditions during pregnancy, you will be treated with antibiotics. For more information on toxoplasmosis, see Toxoplasmosis During Pregnancy.