Food poisoning is an illness caused by eating foods that have harmful organisms in them. These harmful germs can include bacteria, parasites, and viruses. They are mostly found in raw meat, chicken, fish, and eggs, but they can spread to any type of food. They can also grow on food that is left out on counters or outdoors or is stored too long before you eat it. Sometimes food poisoning happens when people don't wash their hands before they touch food.
Most of the time, food poisoning is mild and goes away after a few days. All you can do is wait for your body to get rid of the germ that is causing the illness. But some types of food poisoning may be more serious, and you may need to see a doctor.
The first symptom of food poisoning is usually diarrhea. You may also feel sick to your stomach, vomit, or have stomach cramps. Some food poisoning can cause a high fever and blood in your stool. How you feel when you have food poisoning mostly depends on how healthy you are and what germ is making you sick.
If you vomit or have diarrhea a lot, you can get dehydrated. Dehydration means that your body has lost too much fluid.
Germs can get into food when:
Because most food poisoning is mild and goes away after a few days, most people don't go to the doctor. You can usually assume that you have food poisoning if other people who ate the same food also got sick.
If you think you have food poisoning, call your local health department to report it. This could help keep others from getting sick.
Call your doctor if you think you may have a serious illness. You may need to see your doctor if your diarrhea or vomiting is very bad or if you don't start to get better after a few days.
If you do go to the doctor, he or she will ask you about your symptoms (diarrhea, feeling sick to your stomach, or throwing up), ask about your health in general, and do a physical exam. Your doctor will ask about where you have been eating and whether anyone who ate the same foods is also sick. Sometimes the doctor will take stool or blood samples and have them tested.
In most cases, food poisoning goes away on its own in 2 to 3 days. All you need to do is rest and get plenty of fluids to prevent dehydration from diarrhea. Drink a cup of water or rehydration drink (such as Pedialyte) each time you have a large, loose stool. Soda and fruit juices have too much sugar and shouldn't be used to rehydrate.
Antibiotics usually aren't used to treat food poisoning. Medicines that stop diarrhea (antidiarrheals) can be helpful, but they should not be given to infants or young children. You shouldn't take antidiarrheals if you have a high fever or have blood in the diarrhea, because they can make your illness worse.
If you think you are severely dehydrated, you may need to go to the hospital.
You can prevent most cases of food poisoning with these simple steps:
Food poisoning is an illness caused by eating or drinking contaminated food. You can get food poisoning by eating food contaminated by harmful organisms, such as bacteria, parasites, and viruses.
The most common ways that harmful organisms are spread are:
The symptoms of food poisoning usually affect your stomach and intestines (gastrointestinal tract).
The time it takes for symptoms to appear, how severe the symptoms are, and how long the symptoms last depend on the infecting organism, your age, and your overall health.
The very young and the very old may be most affected by food poisoning. Their symptoms may last longer, and even the types of food poisoning that are typically mild can be life-threatening. This may also be true for pregnant women and people with impaired immune systems, such as those who have long-lasting (chronic) illnesses.
Not all food poisoning causes diarrhea, nausea, vomiting, and belly cramps. Some types of food poisoning have different or more severe symptoms. These can include weakness, numbness, confusion, or tingling of the face, hands, and feet.
Gastrointestinal symptoms, such as diarrhea and vomiting, can also be caused by organisms that aren't necessarily spread through food. These organisms are mainly spread through water or personal contact. Conditions caused by these organisms include infection with the parasite Giardia lamblia.
Learn more about specific food poisoning organisms, including how they are spread, their symptoms, and their treatment:
You may become ill with food poisoning after you eat food that contains bacteria, viruses, or other harmful organisms. Most cases of food poisoning follow the same general course.
After you eat a contaminated food, there is an hours-to-days delay before you notice symptoms. The contaminating organism passes through the stomach into the intestine, attaches to the intestinal walls, and begins to multiply. Some organisms stay in the intestine. Some produce a toxin that is absorbed into the bloodstream. And others directly invade body tissues. Your symptoms depend greatly on the type of organism that has infected you.
Different organisms cause similar symptoms, especially diarrhea, vomiting, and stomach cramps. Diarrhea and vomiting are a normal response as the body tries to rid itself of harmful organisms. Unless the illness is part of a recognized outbreak, it's difficult to identify the infecting organism. Lab tests usually aren't done.
In most cases, you recover in a few days to a week as toxins are flushed from your system. You may feel weak for several days after other symptoms go away.
Most of the time, food poisoning is mild and passes in a few days. But the symptoms and course of some types of food poisoning may be more severe. To learn more, see Symptoms for a list of specific organisms.
In rare cases, food poisoning can result in kidney or joint damage.footnote 2
People at increased risk of becoming ill with food poisoning and of having more severe symptoms include:
Things that increase your risk for getting food poisoning include:
Call 911 or other emergency services immediately if:
Call your doctor now if:
Talk to your doctor if:
If you think you have eaten contaminated food, call your local Poison Control Center. They can answer questions and tell you what to do next.
Watchful waiting is a wait-and-see approach.
Watchful waiting may be okay if you have diarrhea, stomach cramps, and other symptoms of a stomach infection (gastroenteritis). Most people recover from these gastrointestinal illnesses at home in several days without medical treatment. Likewise, some cases of bacterial food poisoning are mild and pass in several days.
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:
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.
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.
Extra precautions should be taken to prevent dehydration in children.
To learn more about treating dehydration, including in children, 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.
For more information on treatment for specific organisms, see Symptoms.
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. To learn more, see Toxoplasmosis During Pregnancy.
You can prevent most cases of food poisoning by being careful when you prepare and store food. Wash your hands and working surfaces while preparing food, cook foods to safe temperatures, and refrigerate foods promptly. Be especially careful when you cook or heat perishable foods, such as eggs, meats, poultry, fish, shellfish, milk, and milk products. Also take extra care if you are pregnant, have an impaired immune system, or are preparing foods for children or older people.
The following steps can help prevent food poisoning (adapted from the U.S. Centers for Disease Control and Prevention).
Many counties in the United States have extension services listed in the phone book. These services can answer your questions about safe home canning and food preparation.
To learn more, see Symptoms for a list of specific organisms.
Most cases of food poisoning will go away in a few days with rest and care at home. The following information will help you recover.
Dehydration is the most frequent complication of food poisoning. Older persons and children should take special precautions to prevent it.
To prevent dehydration, take frequent sips of a rehydration drink (such as Pedialyte). Try to drink a cup of water or rehydration drink for each large, loose stool you have. Sports drinks, soda pop, and fruit juices contain too much sugar and not enough of the important electrolytes that are lost during diarrhea, so they shouldn't be used to rehydrate. You can make your own rehydration drink.
Try to stay with your normal diet as much as possible. Eating your usual diet will help you to get enough nutrition.
Dehydration in children
Take extra precautions to prevent dehydration in children.
For children who are breastfeeding or bottle-feeding, continue the regular breast milk or formula feeding as much as possible. You may have to feed more often to replace lost fluids. Give an oral rehydration solution (ORS), such as Pedialyte, between feedings only if you see signs of dehydration.
For older children, give ½ cup [ 4 fl oz (118 mL)] to 1 cup [ 8 fl oz (237 mL)] of water, milk, or a rehydration drink each hour, and try to keep feeding your child his or her usual diet. Foods to try include potatoes, chicken breast without the skin, cereal, yogurt, and fresh fruits and vegetables. Try to avoid foods that have a lot of fat or sugar. Supplement feedings with small sips or spoonfuls of a rehydration drink or clear liquid every few minutes.
Medicines aren't used routinely in food poisoning. Medicines that stop diarrhea (antidiarrheals) can help with your symptoms. These medicines (such as Imodium) shouldn't be used if you have a fever or bloody diarrhea, because they can actually make you sicker. Don't give antidiarrheals to children.
Types of food poisoning that may be treated with medicines include:
- Centers for Disease Control and Prevention (2010). Campylobacter. Available online: http://www.cdc.gov/nczved/divisions/dfbmd/diseases/campylobacter.
- McGauly PL, Mahler SA (2011). Foodborne and waterborne diseases. In JE Tintinalli, ed., Tintinalli's Emergency Medicine: A Comprehensive Study Guide, 7th ed., pp. 1062–1070. New York: McGraw-Hill.
To learn more about Healthwise, visit Healthwise.org.
© 1995-2021 Healthwise, Incorporated. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.