Sir,
In spite of high prevalence of irritable bowel syndrome (IBS), current treatments have not been satisfied absolutely. The potential role of antidepressant in IBS treatment is increasingly investigated. Until now, a few studies have evaluated the effect of fluoxetine on IBS symptoms, but they had different conclusions.[1,2] Therefore, the author designed a randomized double blinded placebo controlled trail to access the effectiveness of fluoxetine on symptoms and quality-of-life in patients with IBS.
The calculated sample size for this trial was 180 patients in 360 groups to receive either fluoxetine 20 mg, fluoxetine 40 mg or placebo for 12 weeks. They were asked to fill out the questionnaires for IBS symptoms at the beginning and the end of the trial.
A total of 22 patients with IBS (17 women, 4 men, mean age 33/7 years old) participated in the trial during 14 months. In spite of our estimation for 15% drop out in sample, 68% of the patients dropped out due to intolerable side effects specially nausea and dyspepsia in 40 mg group, lack of desire to keep on an experimental trial, long duration of the intervention and unacceptable treatment response. Finally, six patients completed the trial to the end. Two cases in fluoxetine 40 mg group, both alternating type IBS reported relief in gastrointestinal symptoms but not abdominal pain. Two cases in fluoxetine 20 mg group, IBS-constipation predominant and IBS-diarrhea predominant reported slightly relief in gastrointestinal symptoms and abdominal pain. Two cases in the placebo group, IBS-constipation predominant and IBS-diarrhea predominant reported completely relief in gastrointestinal symptoms and abdominal pain.
Investigation of the potential effect of fluoxetine in IBS treatment needs to be evaluated in the larger sample. The limitation of our study included sampling from a tertiary center that explains the small sample size and high rate of drop out.
REFERENCES
- 1.Kuiken SD, Tytgat GN, Boeckxstaens GE. The selective serotonin reuptake inhibitor fluoxetine does not change rectal sensitivity and symptoms in patients with irritable bowel syndrome: A double blind, randomized, placebo-controlled study. Clin Gastroenterol Hepatol. 2003;1:219–28. doi: 10.1053/cgh.2003.50032. [DOI] [PubMed] [Google Scholar]
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