Date of Award


Degree Type

Selective Evidence-Based Medicine Review

Degree Name

Master of Science in Health Sciences - Physician Assistant


Physician Assistant Studies

Department Chair

John Cavenagh, PhD, PA-C


Objective: The objective of this selective EBM review is to determine whether or not the use of antidepressants improves the quality of life and decreases the severity of symptoms in patients with IBS.

Study Design: Review of three English language, double-blind, randomized controlled trials published in 2009.

Data sources: Randomized controlled trials comparing the use of three different antidepressants to a controlled placebo were found on PubMed, OVID and the Cochrane database.

Outcome(s) Measured: Primary end point was overall bowel symptom score at the end of twelve weeks. Secondary end points include individual BSS for each irritable bowel syndrome subset, constipation, pain, or discomfort. Other secondary end points assessed adequate relief of symptoms, IBS-quality of life, and rectal sensitivity. Outcomes were measured through the use of questionnaires.

Results: Three randomized controlled trials were included in this review. The study by Abdul-Baki H. indicated that imipramine was superior to treating IBS when compared to placebo, making this the only therapy evaluated in this review to be effective. Study by Ladabaum U. indicated that citalopram was less effective than placebo. Study by Saito Y. determined that St. John’s Wort was less effective than placebo in decreasing symptoms of IBS.

Conclusions: The results of the study using imipramine concluded that the drug was effective in reducing symptoms and improving quality of life for patients with IBS. The other two studies concluded that the therapy drugs were less effective than the placebo in treating symptoms of IBS. The population studied in some of the studies was not very large and one study had a majority of females which are factors that should be changed in future studies.