Food poisoning occurs when you swallow food or water that contains bacteria, parasites, viruses, or toxins made by these germs. Most cases of food poisoning are from common bacteria such as Staphylococcus or E. coli.
Food poisoning can affect one person or a group of people who all ate the same contaminated food. It more commonly occurs after eating at picnics, school cafeterias, large social functions, or restaurants.
The germs may get into the food you eat (called contamination) in different ways:
Food poisoning often occurs from eating or drinking:
Food poisoning can be caused by:
Infants and elderly people are at the greatest risk for food poisoning. You are also at higher risk if:
Pregnant and breastfeeding women have to be especially careful to avoid food poisoning.
The symptoms from the most common types of food poisoning generally start within 2 - 6 hours of eating the food. That time may be longer (even a number of days) or shorter, depending on the cause of the food poisoning.
Possible symptoms include:
Your health care provider will examine you for signs of food poisoning, such as tenderness in the abdomen and dehydration. Your provider will also ask about foods you have eaten recently.
Tests to find the cause may be done on your:
Even if you have food poisoning, however, these tests may not be able to prove it.
In rare but possibly serious cases, your health care provider may order one or more of the following procedures:
You will usually recover from the most common types of food poisoning within a couple of days. The goal is to make you feel better and avoid dehydration.
If you have diarrhea and are unable to drink fluids (for example, due to nausea or vomiting), you may need medical attention and fluids given through a vein (by IV). This is especially true for young children.
If you take diuretics, you need to manage diarrhea carefully. Talk to your health care provider -- you may need to stop taking the diuretic while you have the diarrhea. Never stop or change medications without talking to your health care provider and getting specific instructions.
For the most common causes of food poisoning, your doctor would NOT prescribe antibiotics.
You can buy medicines at the drugstore that help slow diarrhea. Do not use these medicines without talking to your health care provider if you have bloody diarrhea or a fever. Do not give these medicines to children.
If you have eaten toxins from mushrooms or shellfish, you will need medical attention right away. The emergency room doctor will take steps to empty out your stomach and remove the toxin.
Most people fully recover from the most common types of food poisoning within 12 - 48 hours. Serious complications can arise, however, from certain types of food poisoning.
Dehydration is the most common complication. This can occur from any of the causes of food poisoning.
Less common but much more serious complications include:
Call your health care provider if:
Go to the emergency room or call 911 if:
See: Preventing food poisoning