Prevention

Watch what you eat

The general rule of thumb when traveling to another country is this: Boil it, cook it, peel it or forget it. But, it's still possible to get sick even if you follow these rules.

Other tips that may help decrease your risk of getting sick include:

• Don't consume food from street vendors.
• Avoid unpasteurized milk and dairy products, including ice cream.
• Avoid raw or undercooked meat, fish and shellfish.
• Steer clear of moist food at room temperature, such as sauces and buffet offerings.
• Eat foods that are well cooked and served hot.
• Stick to fruits and vegetables that you can peel yourself, such as bananas, oranges and avocados. Stay away from salads and from fruits you can't peel, such as grapes and berries.
• Be aware that alcohol in a drink won't keep you safe from contaminated water or ice.

Don't drink the water

When visiting high-risk areas, keep the following tips in mind:

• Avoid unsterilized water — from tap, well or stream. If you need to consume local water, boil it for three minutes. Let the water cool naturally and store it in a clean covered container.
• Avoid locally made ice cubes or mixed fruit juices made with tap water.
• Beware of sliced fruit that may have been washed in contaminated water.
• Use bottled or boiled water to mix baby formula.
• Order hot beverages, such as coffee or tea, and make sure they're steaming hot.
• Feel free to drink canned or bottled drinks in their original containers — including water, carbonated beverages, beer or wine — as long as you break the seals on the containers yourself. Wipe off any can or bottle before drinking or pouring.
• Use bottled water to brush your teeth.
• Don't swim in water that may be contaminated.
• Keep your mouth closed while showering.

If it's not possible to buy bottled water or boil your water, bring some means to purify water. Consider a water-filter pump with a microstrainer filter that can filter out small microorganisms.

You can also chemically disinfect water with iodine or chlorine. Iodine tends to be more effective, but is best reserved for short trips, as too much iodine can be harmful to your system. You can purchase water-disinfecting tablets containing chlorine, iodine tablets or crystals, or other disinfecting agents at camping stores and pharmacies. Be sure to follow the directions on the package.

Follow additional tips

Here are other ways to reduce your risk of traveler's diarrhea:

• Make sure dishes and utensils are clean and dry before using them.
• Wash your hands often and always before eating. If washing isn't possible, use an alcohol-based hand sanitizer with at least 60% alcohol to clean your hands before eating.
• Seek out food items that require little handling in preparation.
• Keep children from putting things — including their dirty hands — in their mouths. If possible, keep infants from crawling on dirty floors.
• Tie a colored ribbon around the bathroom faucet to remind you not to drink — or brush your teeth with — tap water.

Other preventive measures

Public health experts generally don't recommend taking antibiotics to prevent traveler's diarrhea, because doing so can contribute to the development of antibiotic-resistant bacteria.

Antibiotics provide no protection against viruses and parasites, but they can give travelers a false sense of security about the risks of consuming local foods and beverages. They can also cause unpleasant side effects, such as skin rashes, skin reactions to the sun and vaginal yeast infections.

As a preventive measure, some doctors suggest taking bismuth subsalicylate, which has been shown to decrease the likelihood of diarrhea. However, don't take this medication for longer than three weeks, and don't take it at all if you're pregnant or allergic to aspirin. Talk to your doctor before taking bismuth subsalicylate if you're taking certain medications, such as anticoagulants.

Common harmless side effects of bismuth subsalicylate include a black-colored tongue and dark stools. In some cases, it can cause constipation, nausea and, rarely, ringing in your ears (tinnitus).