Low dose antidepressant therapy can significantly improve the overall quality of life for adolescents suffering from Irritable Bowel Syndrome (IBS), according to a new study.

The study, conducted by researchers at Mattel Children's Hospital UCLA (University of California, Los Angeles), is the first of its kind to look at the effects of amitriptyline, a tricyclic antidepressant, in the pediatric IBS population, researchers said.

The research was conducted between 2002 and 2005 and involved 33 newly diagnosed IBS patients, including 24 girls, between the ages of 12 and 18.

Irritable bowel syndrome causes discomfort in the abdomen, along with diarrhea, constipation or both. Currently, there is no cure, and treatments only lessen the symptoms.

"While research has shown that amitriptyline is effective for adults with IBS, only peppermint oil has been studied in children with this disorder in a double-blind, placebo-controlled fashion," said Dr. Ron J. Bahar, assistant clinical professor of pediatric gastroenterology at Mattel Children's Hospital UCLA and lead author of the study.

"Our results show that amitriptyline significantly improves overall quality-of-life measurements in adolescents and should be a therapeutic option for these patients. We were actually surprised to reach our conclusion with a relatively small number of subjects," J. Bahar said.

The 13-week study consisted of three phases: two weeks of enrollment and symptom scoring, eight weeks of therapy with amitriptyline or a placebo, and three weeks of post-medication "washout" and symptom scoring.

Patients were randomized in a double-blinded fashion to receive the antidepressant or a placebo and were surveyed at two, six, 10 and 13 weeks using a symptom checklist, a pain-rating scale, a pain intensity and frequency scale, and an IBS quality-of-life questionnaire.

The results showed that patients receiving amitriptyline were more likely to experience: an improvement in overall quality of life at six, 10 and 13 weeks, a reduction in IBS-associated diarrhea at six and 10 weeks, reduction in pain near the belly button at 10 weeks and reduction in pain in the right lower quadrant of the abdomen at six, 10 and 13 weeks.

"However, the dose of AMI (amitriptyline) used in this study, as well as IBS treatment for adults, is far less than the dose to treat depression. At these low levels, it could be considered a remedy to treat neuropathic pain associated with chronic pain symptoms, rather than an antidepressant or psychotropic medication," Bahar said.