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Traveler’s Diarrhea



Jonathan Gotfried

, MD, Lewis Katz School of Medicine at Temple University

Reviewed/Revised Oct 2021 | Modified Sep 2022

Traveler’s diarrhea is an infection characterized by diarrhea, nausea, and vomiting that commonly occur in travelers to areas of the world with poor water purification.

  • Traveler's diarrhea can be caused by bacteria, parasites, or viruses.

  • Organisms that cause the disorder are usually acquired from food or water, especially in developing countries where the water supply may be inadequately treated.

  • Nausea, vomiting, abdominal cramping, and diarrhea can occur with any degree of severity.

  • The diagnosis is usually based on the doctor's evaluation, but sometimes stool is tested for organisms.

  • Preventive measures include drinking only bottled carbonated beverages, avoiding uncooked vegetables or fruits, not using ice cubes, and using bottled water to brush teeth.

  • Treatment involves drinking plenty of safe fluids and sometimes taking antidiarrheal drugs or antibiotics.

Traveler’s diarrhea occurs when people are exposed to bacteria, viruses, or, less commonly, parasites to which they have had little exposure and thus no immunity. The organisms are usually acquired from food or water (including water used to wash foods). Traveler’s diarrhea occurs mostly in countries where the water supply is inadequately treated. The bacteria Escherichia coli (E. coli) is the organism most likely to cause traveler’s diarrhea, particularly the types of E. coli that produce certain toxins E. coli Gastroenteritis E. coli gastroenteritis is a type of gastroenteritis in which certain strains of the bacterium Escherichia coli infect the large intestine and cause diarrhea and sometimes other... read more <i >E. coli</i> Gastroenteritis and some viruses such as norovirus Norovirus Gastroenteritis Gastroenteritis is inflammation of the lining of the stomach and small and large intestines. It can be caused by the norovirus. Norovirus is very contagious and spreads from person to person... read more Norovirus Gastroenteritis , which has been a particular problem on some cruise ships.

Travelers who avoid drinking local water may still become infected by brushing their teeth with an improperly rinsed toothbrush, drinking bottled drinks with ice made from local water, or eating food that is improperly handled or washed with local water. People who take drugs that decrease stomach acid (such as antacids, H2 blockers, and proton pump inhibitors) are at risk of developing a more severe illness.

Symptoms of Traveler’s Diarrhea

The following symptoms of traveler's diarrhea can occur in any combination and with any degree of severity:

  • Nausea

  • Vomiting

  • Intestinal rumbling

  • Abdominal cramping

  • Diarrhea

  • Fever

These symptoms begin 12 to 72 hours after ingesting contaminated food or water. Vomiting, headache, and muscle pain are particularly common in infections caused by norovirus. Rarely, diarrhea is bloody. Most cases are mild and disappear without treatment within 3 to 5 days.

Diagnosis of Traveler’s Diarrhea

  • A doctor's evaluation

  • Rarely stool tests

Diagnostic tests are rarely needed, but sometimes stool samples are tested for bacteria, viruses, or parasites.

Prevention of Traveler’s Diarrhea

  • Safe consumption of food and water

Travelers should eat only in restaurants with a reputation for safety and should not consume any food or beverages from street vendors. Cooked foods that are still hot when served are generally safe. Salads containing uncooked vegetables or fruit and salsa left on the table in open containers should be avoided. Any fruit should be peeled by the traveler. Travelers should drink only bottled carbonated beverages or beverages made with water that has been boiled. Even ice cubes should be made with water that has been boiled. Buffets and fast food restaurants pose an increased risk of infection.

Preventive antibiotics are recommended only for people who are particularly susceptible to the consequences of traveler’s diarrhea, such as those whose immune system is impaired, those who have inflammatory bowel disease, those who have HIV, those who have received an organ transplant, and those who have severe heart or kidney disease. The antibiotic most commonly recommended is rifaximin.

Treatment of Traveler’s Diarrhea

  • Fluids

  • Drugs that stop diarrhea (antidiarrheal drugs)

  • Sometimes antibiotics or antiparasitic drugs

When symptoms occur, treatment includes drinking plenty of fluids and taking drugs that stop diarrhea such as loperamide. These drugs are not given to children under 2 years of age, and their use is limited in children 2 to 18 years of age. Antidiarrheal drugs are also not given to people who have recently used antibiotics, who have bloody diarrhea, who have small amounts of blood in the stool that are too small to be seen, or who have diarrhea and fever. Antibiotics are not necessary for mild traveler's diarrhea.

If diarrhea is more severe (3 or more loose stools over 8 hours), antibiotics are usually recommended (for adults, ciprofloxacin, levofloxacin, azithromycin, or rifaximin and, for children, azithromycin). Antibiotics are not given if a virus is the cause. Antiparasitic drugs are given if a parasite is identified in the stool.

Travelers are encouraged to seek medical care if they develop fever or blood in the stool.

More Information

The following English-language resource may be useful. Please note that THE MANUAL is not responsible for the content of this resource.

Drugs Mentioned In This Article

Generic Name Select Brand Names
Anti-Diarrheal, Imodium A-D, Imodium A-D EZ Chews , K-Pek II
Cetraxal , Ciloxan, Cipro, Cipro XR, OTIPRIO, Proquin XR
Azasite, Zithromax, Zithromax Powder, Zithromax Single-Dose , Zithromax Tri-Pak, Zithromax Z-Pak, Zmax, Zmax Pediatric
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