The most common problem encountered by visitors to foreign countries is traveler's diarrhea. Traveler's diarrhea is caused by consuming contaminated food or drink. Food purchased from street vendors, in particular, is often unsafe. However, diarrhea may also result from less obvious sources, such as brushing one's teeth with contaminated water, or eating with dirty utensils. Generally, bottled or canned carbonated drinks, or drinks made with boiled water, are safe, and cooked food is relatively safe if it is eaten while still hot.
Fruits are less likely to cause diarrhea if they are peeled immediately before being eaten.
There are a number of medications which are usually effective for treating diarrhea, such as Pepto-Bismol, Imodium, or Lomotil. Affected persons should take lots of liquids, such as noncaffeinated bottled drinks or soup. Several of the diseases common in Cambodia are transmitted by mosquitos. Some simple precautions can greatly decrease the risk of contracting these diseases. Wear long-sleeved shirts and long pants, and try to remain indoors as much as possible after sunset.