Kalloo, the director of gastroenterology and hepatology at The Johns Hopkins Hospital.

CNN: Coming clean about my first colonoscopy

If these drugs, which tend to suppress the immune system, are given in doses that are too high, the immune system can be compromised, says Robert Summers, a professor in gastroenterology and hepatology at the University of Iowa who helped run the trials.

WSJ: In a Squeaky-Clean World, a Worm Might Help Fight Disease

Abstract of presentation to the North American Society of Pediatric Gastroenterology, Hepatology, and Nutrition, Annual Meeting, October 20-22, 2005, Salt Lake City, Utah.

FORBES: Anti-Vaccine Activists Apparently Immune To Science