Diagnosis

A diagnosis is based on a physical exam and a review of things that may be causing vomiting, diarrhea or other symptoms. Questions from your health care provider will cover:

  • Your symptoms.
  • Food or drinks you've had recently.
  • Symptoms in people who ate with you.
  • Recent changes in the drugs you take.
  • Recent travel.

Your health care provider will examine you to rule out other causes of illness and check for signs of dehydration.

Your provider may order tests including:

  • Stool sample tests to name the bacteria, viruses, parasites or toxins.
  • Blood tests to name a cause of illness, rule out other conditions or identify complications.

When one person or a family gets food poisoning, it's hard to know what food was contaminated. The time from eating the contaminated food to the time of sickness can be hours or days. During that time, you may have had one or several more meals. This makes it difficult to say what food made you sick.

In a large outbreak, public health officials may be able to find the common food all of the people shared.

Treatment

Treatment for food poisoning depends on how severe your symptoms are and what caused the illness. In most cases, drug treatment isn't necessary.

Treatment may include the following:

  • Fluid replacement. Fluids and electrolytes, maintain the balance of fluids in your body. Electrolytes include minerals such as sodium, potassium and calcium. After vomiting or diarrhea, it's important to replace fluids to prevent dehydration. Severe dehydration may require going to the hospital. You may need fluids and electrolytes delivered directly into the bloodstream.
  • Antibiotics. If the illness is caused by bacteria, you may be prescribed an antibiotic. Antibiotics are generally for people with severe disease or with a higher risk of complications.
  • Antiparasitics. Drugs that target parasites, called antiparasitics, are usually prescribed for parasitic infections.
  • Probiotics. Your care provider may recommend probiotics. These are treatments that replace healthy bacteria in the digestive system.

Drugs for diarrhea or upset stomach

Adults who have diarrhea that isn't bloody and who have no fever may take loperamide (Imodium A-D) to treat diarrhea. They also may take bismuth subsalicylate (Pepto-Bismol, Kaopectate, others) to treat an upset stomach. These nonprescription drugs are not recommended for children.

Ask your doctor about these options.

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Lifestyle and home remedies

For most people, symptoms improve without treatment within 48 hours. To help keep yourself more comfortable and prevent dehydration while you recover, try the following:

  • Let your stomach settle. Eat after your stomach is settled and you are hungry again.
  • Replace fluids. Replace fluids with water, sports drinks, juice with added water or broths. Children or people at risk for serious illness should drink rehydration fluids (Pedialyte, Enfalyte, others). Talk to your doctor before giving rehydration fluids to infants.
  • Ease back into eating. Gradually begin to eat bland, low-fat, easy-to-digest foods, such as soda crackers, toast, gelatin, bananas and rice. Stop eating if you feel sick to your stomach again.
  • Avoid certain foods and substances until you're feeling better. These include dairy products, caffeine, alcohol, nicotine, and fatty or highly seasoned foods.
  • Rest. Rest to recover from illness and dehydration.

Preparing for your appointment

You'll likely see your primary health care provider. In some cases, you may need to see a specialist in infectious diseases.

Be prepared to answer the following questions.

  • When did your symptoms begin?
  • Have the symptoms been continuous, or do they come and go?
  • Have you had bloody diarrhea or stools?
  • Have you had black or tarry stools?
  • Have you had a fever?
  • What have you recently eaten?
  • Did anyone who ate the same food have symptoms?
  • Have you recently traveled? Where?
  • What drugs, dietary supplements or herbal remedies do you take?
  • Had you taken antibiotics in the days or weeks before your symptoms started?
  • Have you recently changed medications?
Feb. 23, 2024
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  2. Definition & facts of food poisoning. National Institute of Diabetes and Digestive and Kidney Diseases. https://www.niddk.nih.gov/health-information/digestive-diseases/food-poisoning/definition-facts. Accessed Nov. 7, 2022.
  3. Symptoms & causes of food poisoning. National Institute of Diabetes and Digestive and Kidney Diseases. https://www.niddk.nih.gov/health-information/digestive-diseases/food-poisoning/symptoms-causes. Accessed Nov. 7, 2022.
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  12. LaRocque R. Approach to the adult with acute diarrhea in resource-rich settings. https://www.uptodate.com/contents/search. Accessed Nov. 7, 2022.
  13. Treatment for food poisoning. National Institute of Diabetes and Digestive and Kidney Diseases. https://www.niddk.nih.gov/health-information/digestive-diseases/food-poisoning/treatment. Accessed Nov. 7, 2022.
  14. Eating, diet and nutrition for food poisoning. National Institute of Diabetes and Digestive and Kidney Diseases. https://www.niddk.nih.gov/health-information/digestive-diseases/food-poisoning/eating-diet-nutrition. Accessed Nov. 20, 2022.
  15. Four steps to food safety: Clean, separate, cook, chill. U.S. Centers for Disease Control and Prevention. https://www.cdc.gov/foodsafety/keep-food-safe.html. Accessed Nov. 7, 2022.
  16. Leftovers and food safety. U.S. Department of Agriculture. https://www.fsis.usda.gov/food-safety/safe-food-handling-and-preparation/food-safety-basics/leftovers-and-food-safety. Accessed Nov. 20, 2022.
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