Irritable bowel syndrome is a disease of unknown cause, characterized by abdominal pain with either diarrhea or constipation. Many past studies have yielded contradictory and confusing results about the usefulness of fiber, antispasmodics (drugs which reduce stomach contractions), and peppermint oil in treating this disease. This review, a meta-analysis of many such studies, attempted to investigate the efficacy of these agents. This review concludes that “fiber, antispasmodics and peppermint oil were all more effective than placebo in the treatment of irritable bowel syndrome.”
Irritable bowel syndrome is a functional disturbance of the gut, in which no abnormality is visible in the gut, although the patient suffers from symptoms. It is thought that this disease occurs because of hypersensitivity of the gut to stimuli and pain. The prevalence of this disease varies from 5 to 20 percent worldwide. Once affected, patients of this disease experience chronic but intermittent symptoms. There is a need to develop simple therapeutic measures, as most newly discovered drugs for this disease, apart from being expensive, fail to produce the desired effects. Patients with irritable bowel syndrome are often treated by general practitioners. Proving the efficacy of such simple drugs would possibly encourage general practitioners to use such drugs. In the present review, a systematic meta-analysis of 48 articles was done to analyze the effect of fiber, antispasmodics, and peppermint oil in the treatment of irritable bowel syndrome.
This meta-analysis included 12 studies done on the effects of fiber, 22 studies on antispasmodics and four studies on peppermint oil. In all these studies, a clinical trial was done to compare the effects of the drug with placebo or no-treatment condition. These studies were obtained from searching Medline, Cochrane and Embase databases. In all of these studies patients were given treatment for a minimum duration of one week. In the fiber category, some studies were done on bran and some on ispaghula. In antispasmodic category, effects of various different antispasmodics were analyzed.
* Overall, 52 percent of patients assigned to the fiber group had persistent or unimproved symptoms after treatment compared with 57 percent in the placebo group. This beneficial effect was more pronounced with ispaghula while no significant effect was observed with bran.
* About 39 percent of people who were treated with antispasmodics continued to have symptoms. This was 56 percent with placebo. Hyoscine was the most effective antispasmodic.
* Only 26 percent of patients receiving peppermint oil had persistent symptoms, while 65 percent in the control group continued to suffer symptoms.
* Very few adverse effects were observed with the use of all the three therapeutic agents. Side effects increased with the use of antispasmodics.
According to the Jadad scale, which measures the quality of clinical trials, most of the studies included in the present review were moderate to good. In many studies, The Rome criteria to identify irritable bowel syndrome were not applied in all but five of the reviewed studies. Because of the smell of peppermint oil and the texture of ispaghula, participants in the test group were aware that they were consuming that particular drug. This creates bias and results in false findings.
This review has shown that fiber, antispasmodics and peppermint oil are useful in the management of patients suffering from irritable bowel syndrome. Ispaghula is a better option for fiber, and hyoscine is a better antispasmodic, as per the studies reviewed. Recent studies using magnetic resonance imaging have shown that irritable bowel syndrome symptoms include contractions of the gut, which leads to faster transit of food in the intestine. Antispasmodics reduce contractions, while fiber slows down food movement. Moreover, all these drugs are very safe and can be obtained over the counter. Hence they can be safely used as the first line of treatment before trying the newer expensive drugs. Findings of this meta-analysis must be considered while framing the new guidelines for treatment of irritable bowel syndrome.
For More Information:
Effect of Fiber, Antispasmodics, and Peppermint Oil in the Treatment of Irritable Bowel Syndrome
Publication Journal: British Medical Journal, 2008
By Alexander C. Ford; Nicholas J. Talley; McMaster University, Hamilton, Ontario, Canada and Mayo Clinic Florida, Jacksonville, Florida