Adult Traveler's Diarrhea
The most common medical problem befalling international travelers is a gastrointestinal infection-producing diarrhea. Travelers’ diarrhea refers to an acute illness of sudden onset with watery diarrhea, abdominal cramps, mild nausea without much vomiting, and general malaise.
The disease occurs in travelers to underdeveloped countries, where poor sanitation promotes ingestion of contaminated food or water. In third world countries, animal and human waste is the predominant form of agricultural fertilizer. Application of this fecal material to food crops leaves a thin film of contamination on the outside of fruits or vegetables. The food in turn transmits bacterial and viral induced diarrheal illnesses. The local populace is generally immune by long exposure; travelers are not. In contrast, developed countries use industrial fertilizer this is an inorganic manufactured material, eliminating this problem.
The watery diarrhea associated with such infections is usually self-limited, resolving in 4-6 days. Unfortunately, however, it represents a significant inconvenience to travelers with busy itineraries and relatively short vacations. Consequently, symptomatic treatment of travelers’ diarrhea is appropriate and important. Prophylactic antibiotic treatment on the other hand is not considered safe or particularly efficacious. If a diarrhea illness is accompanied by high fever (higher than 101°), severe abdominal pain, passage of bloody stools or unrelenting vomiting, medical care should be sought, instead of initiating the self-treatment outlined below.
Prevention of Traveler’s Diarrhea
Prevention of diarrhea is possible with some foresight, by selecting safe food and water while traveling. Food should be thoroughly cooked. Uncooked dishes, salads, raw fruits, vegetables, and dairy products should be avoided. Fruits, from which a peel can be removed such as bananas or oranges, are safe. Bottled or boiled water should be used only, both for drinking and for brushing one’s teeth. Ice cubes and non-boiled cold drinks should not be ingested. It is safest to eat only obviously hot, well-cooked food items in hotels, restaurants, and homes. The sanitation of small cafes and street vendors must be suspect.
Treatment of Traveler’s Diarrhea
There are three aspects of treatment. The most important is to avoid dehydration, due to loss of body fluids. Diarrhea is a salty, high potassium liquid that can rapidly result in weakness and lightheadedness on the basis of fluid loss and electrolyte imbalance. Recommended fluids are those that contain, both sodium and potassium, as well as sugar. The sugar is important to facilitate the absorption of the salts. The replenishing fluid should be safe, i.e. noninfectious – one does not want to get a second infection on top of the first. Examples of fluids are the W.H.O. oral hydration formula, Pedialyte for Children, canned fruit juices, and Gatorade (8 ounces mixed with ¼ tsp of Morton’s Light Salt supplies more sodium and potassium). These should be taken in sufficient quantities to quench thirst to produce a moderate urine output.
Antimotility agents such as Imodium or Lomotil are of some benefit. In the past it was thought that such drugs may prolong the diarrhea illness, but that has not been shown to be the case. They are generally considered safe as long as there is neither high fever nor blood in the stool. These agents simply decrease the frequency of stooling. They do not have an effect on the amount of fluid loss or diarrhea. Hence, diarrhea will be more voluminous when it occurs but will not occur as frequently. Imodium is available over-the-counter in the United States. Lomotil is a prescription item. Either should be used per the package directions.
Traveler’s diarrhea can be treated with antibiotics including Cipro or azithromycin. These agents can be combined safely with antimotility drugs mentioned above. These drugs are not safe in pregnancy or individuals with allergies to them. Sunscreen should be worn when taking Doxycycline or Bactrim, since either of them can enable a sun induced itchy rash.
Parasitic Diarrheas are common in developing countries. They are unresponsive to the above course of therapy, so any diarrhea illness that persists beyond several days and has been unresponsive to antibiotic therapy may represent a parasitic infection that requires medical attention. For the wilderness traveler, empiric therapies, which may be appropriate to have along, are available for prolonged diarrheal illnesses. This can be discussed with your travel medicine physician.
Finally, as preventative therapy, Pepto-Bismol has been shown to decrease travelers’ diarrhea by half. The dosage is two tablets before meals and at bedtime. Stools and tongue may turn black at that dose. Although safe for weeks, Pepto-Bismol should not be extended indefinitely, and because it is salicylate based, should not be given to children.