Gastroenteritis — The Basics

Case study: A 45 year old woman eats leftovers of sushi and salad (1 day in fridge). Two days later, she has diarrhea, stomach cramps, gas, and vomiting…

The Basics

Literally, gastroenteritis means “inflammation of the stomach”. This is the treaded traveler’s diarrhea, also known as Turista. It is an infection of the stomach tract, usually from contaminated food. In developed countries, this is usually caused by a virus and not treated with antibiotics. But in developing countries such as China, it’s much more commonly caused by bacteria, or also a parasite. This is why many travel doctors recommend antibiotics (but not always).

Why So Common?

This is usually a hygiene problem; the food got contaminated somewhere along the chain:

  • in the field (farm animal feces)
  • during shipping and storage (not temperature controlled)
  • during preparation (hand washing, cross contamination, not cooked well)
  • during serving (cook, server, fellow diners sharing utensils)

The Symptoms

Bacteria : Common symptoms include diarrhea (>3 loose stools per day); nausea; vomiting; cramps; no appetite. Less common are fever, blood in stool. Serious symptoms include dehydration. The usual course: starts within 2 weeks of ingestion. Lasts 1-4 days

Parasite: Parasite infections are usually much more subtle and slower onset than other infections; you may have slight cramps and bloating with occasional loose stools, which sometimes last for many weeks. A fever is uncommon. Dehydration is also rare, but if a child has a parasite for months, they could experience weight loss, fatigue and poor school performance.


Unfortunately, no matter how obsessive-compulsive you are, you have a good chance of eventually developing traveler’s diarrhea. A recent study compared these fastitious types with more casual travelers (the ones that would still eat ice cubes, etc) — and lo and behold, both groups got equally infected! I actually find this comforting; we should all relax just a bit while traveling.

But of course, it is best to follow some common sense rules:

  • Hand washing: this is crucial for everyone, not just the cooks. It is especially important after using the toilet. Far too many Chinese toilets still do not have proper soap and towels, so I always carry around Purell-style alcohol gel. The gel kills germs much more effectively — and much quicker — than soap and water. Keep one in your bag, on your desk at work…
  • At home: fruits and veggies — anything that can be peeled, should be! I would not assume that an imported apple would be any safer than local product; there could be pesticides on those, and they traveled long and far to get here. Better to be safe. Leafy greens, especially spinach, should be washed well. I highly recommend the Veggie Wash citrus spray, found in most expat markets. This natural spray kills most bugs and also helps wash off pesticides. As for meats and fish, make sure you cook it well — after inspecting it, and of course after washing your hands.
  • Restaurants: Even a 5-star can have infected foods, if the busboy or chef didn’t wash their hands properly. Also, look for the Beijing Health Department sanitation ratings at the front door. It’s usually a big blue sign with letters on it; A is top, B is ok. If you see C or D, then maybe you should think twice before entering.
  • Street food: buyer beware! For obvious sanitary reasons, the food here is riskier. Food poisoning is also much more common, especially in the summer months. If any food is left out in the heat for only one hour, the bacteria start multiplying. And where is the cook’s bathroom, or fridge, or cutting boards? Something to ponder…



  • Lomotil is the best choice to slow down non-serious diarrhea (aka not bloody). This medicine will slow down diarrhea for almost everyone. But some people don’t like the feeling, and it doesn’t make the infection go away quicker.
  • Smecta – charcoal. This powder is usually taken for 3 days; it helps to firm up the stool and also decreases the overall severity a bit — if you can tolerate the taste. There’s a new strawberry flavor for kids and queasy adults.
  • Medilac-S: this is “good bacteria”, a powder you put in water 3 times a day. It helps replenish your stomach with healthy bacteria, and also improves overall symptoms and length. Good stuff. Also has a kids version Medilac-Vita.

Nausea: ginger (jiang) is great in any form for nausea and stomach cramps. Mints usually also work well, as do salt crackers. Doctors can prescribe stronger medicines.

Dehydration: This is the #1 problem with diarrhea; thousands of children die needlessly every year in poverty-stricken regions worldwide due to lack of access to simple rehydration salts. You can buy these packets in clinics (Oral Rehydration Salts) and keep in the house or while traveling.
It’s important to realize that if you can’t keep any foods down, just drinking water is not enough to stay hydrated; you need salt and sugar as well. The salt packets are best for infants; mild diarrhea in adults usually can be handled with some type of clear broth soup (chicken soup with ginger; miso; wonton), or Pocari Sweat-type bottled waters. Be aware that some juices make your diarrhea more watery.
Healthy foods: Try salt crackers to get some basic nutrients. Leafy steamed greens with garlic and vinegar are great — and on every Chinese menu. Soups and rice broth (zhou) are a good start.

When To Go To The Doctor

Most gastro is easily managed at home with OTC medicines and a bit of TLC. If your diarrhea or vomiting is severe, or you feel dehydrated, or have a very high fever, you should see your doctor. But overall, for the average gastro, there’s nothing wrong with waiting a few days. And no, you don’t automatically need antibiotics. Even if it is bacterial, much of the time your body’s immune system can handle it just fine. A general rule — diarrhea for one week (7 days), even if mild, is probably not viral and needs evaluation.

In Your Travel Kit

The second worse problem, when traveling and developing diarrhea, is not to have medicine ready! It’s always a good idea to throw some basics into your carry-on:

  • Lomotil (aka immodium) – most important, especially to get you through a long flight
  • Antibiotic – it’s not a bad idea to carry either ciprofloxacin or azithromycin. Your doctor will need to prescribe this.
  • Others: Smecta (charcoal); medilac; bismuth (Pepto-Bismol)

Slide Show

I created a simple slide show about gastroenteritis, which you can watch full-screen below by clicking on the Menu button:

(Most of this text is a reprint from a year ago here…)

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