FDA Finds Possible New Risks of Bowel DrugApr 28, 2004 | AP Some users of the irritable-bowel treatment Zelnorm have suffered diarrhea so serious they require hospitalization, and four have died from an intestinal problem, the government said Wednesday.
The agency ordered that a precaution about the intestinal condition go on Zelnorm's label, along with a larger warning about severe diarrhea.
Irritable bowel syndrome is a mysterious disorder that gives millions of people, mostly women, abdominal pain and either severe diarrhea or constipation or both. Zelnorm is the only FDA-approved therapy for the constipation-causing form of the ailment. It is supposed to be used only by women.
The drug speeds the colon's movement of stools, so diarrhea is a potential side effect. But the FDA has 21 reports of diarrhea so severe that it caused such complications as low blood pressure and fainting. Sixteen patients required hospitalization, said the FDA's Dr. Robert Justice.
Zelnorm should not be used by anyone who frequently experiences diarrhea, and should be stopped immediately if patients get dizzy or faint, the FDA said.
As for the intestinal inflammation, there were no cases of ischemic colitis in studies of 7,000 Zelnorm patients. But since Zelnorm went on sale in 2002, the FDA has received 20 reports of ischemic colitis, plus three reports of a similar intestinal problem, Justice said. Fourteen patients were hospitalized. Four died, although they had numerous other serious medical conditions, he said.
The FDA advised patients who experience new or worsened abdominal pain or blood in their stools ischemic colitis symptoms to stop taking the drug and call a doctor.