Oct. 28, 2008 (Washington, D.C.) -- An experimental antibiotic has been shown to cut short the curse of many trips abroad: traveler's diarrhea.
Researchers studied nearly 300 American students who were struck by diarrhea while visiting Mexico or Peru. Those who took the new pill, known as prulifloxacin, "were totally well within a day," says researcher Herbert DuPont, MD, director of the Center for Infectious Diseases at the University of Texas School of Public Health in Houston.
In contrast, more than half of the students who took a placebo still had diarrhea five days later, DuPont tells WebMD. "Prulifloxacin was generally well-tolerated, with a safety profile identical to that of placebo."
The findings were presented here at a joint meeting of the American Society for Microbiology and the Infectious Diseases Society of America.
Millions of Travelers Struck Each Year
Intestinal illness caused by contaminated food and drink is the most common malady afflicting international travelers, particularly in developing countries.
Of the 100 million travelers who visit developing tropical countries each year, about 40% develop agonizing bouts of diarrhea and cramping that last for days, DuPont says.
Up to 10% of them go on to develop irritable bowel syndrome, or IBS, a chronic disorder of the intestines that causes belly pain, cramping or bloating, and diarrhea or constipation, he says. "Traveler's diarrhea is a bigger deal that we thought, causing this syndrome that can last for years, even decades."
Once-Daily Dosing an Advantage
The reason antibiotics work so well against travelers' diarrhea is that about 80% of cases are caused by bacteria, DuPont says. In contrast, only about 10% to 15% of cases of diarrheal illness in the U.S. are caused by bacteria, he says.
Mary MacGregor, DO, of The Travel Medicine Source in Morton Grove, Ill., says the antibiotic Cipro is often used to treat travelers' diarrhea. But new options are always "reasonable," she says. MacGregor was not involved with the study.
DuPont says an advantage of prulifloxacin is that it only has to be taken once a day. In contrast, Cipro and Noroxin, another antibiotic commonly used to treat travelers' diarrhea, are typically taken twice a day, according to the CDC.
Prulifloxacin is already on the market in Japan, Italy, and some other countries, where it is mainly used to treat urinary tract infections.
The new study was supported by Optimer Pharmaceuticals Inc., which makes the drug.