The studies were presented in Los Angeles, at Digestive Disease Week 2006, an international meeting of doctors, researchers, and academics.
One of the studies used cognitive behavioral therapy to teach IBS patients new ways to handle their condition. The other two studies tested hypnosis in IBS patients who hadn't been helped by other treatments.
Cognitive behavioral therapy and hypnosis were each linked to improvements in gastrointestinal symptoms, the studies show.
The hypnosis researchers included Magnus Simren, MD, of Sahlgrenska University Hospital's internal medicine department in Gothenburg, Sweden.
Hypnotherapy is already used to treat IBS patients, mainly at a few highly specialized gastrointestinal centers, Simren told reporters in a conference call. His team used two more common settings: a university hospital and a county hospital.
Exactly how hypnosis helps IBS isn't clear. Simren, a gastroenterologist, admits having his doubts that patients would give it a try.
"When I started with this, I was a little bit afraid that patients would be hesitant, that they would think this is hocus-pocus. But they are very open-minded to this," he says.
"When I speak to the patient, I tell them that this is a way that you can get control over your symptoms," says Simren. "They are quite satisfied with that explanation."