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One of the most important therapeutic measures is reassuring the patient that they have no fatal or otherwise threatening disease, because this is the major concern of patients seeking medical help. Dietary advice may be given and medication is an option in most forms.
A questionnaire in 2006 designed to identify patients’ perceptions about IBS, their preferences on the type of information they need, as well as educational media and expectations from health care providers, revealed misperceptions about IBS developing into other conditions, including colitis, malnutrition, and cancer.
The survey found IBS patients were most interested in learning about foods to avoid (60%), causes of IBS (55%), medications (58%), coping strategies (56%), and psychological factors related to IBS (55%). The respondents indicated that they wanted their physician to be available via phone or e-mail following a visit (80%), have the ability to listen (80%), and provide hope (73%) and support (63%).
Diet
There are a number of dietary changes a person with IBS can make to prevent the overreaction of the gastrocolic reflex and lessen pain, discomfort, and bowel dysfunction. Having soluble fiber foods and supplements, substituting soy or rice products for milk products, being careful with fresh fruits and vegetables that are high in insoluble fiber, and eating frequent meals of small amounts of food, can all help to lessen the symptoms of IBS. Foods and beverages to be avoided or minimized include red meat, oily or fatty and fried products, milk products (even when there is no lactose intolerance), solid chocolate, coffee (regular and decaffeinated), alcohol, carbonated beverages (especially those also containing sorbitol), and artificial sweeteners. However, care should be taken to avoid adding foods to the diet to which the patient is allergic or intolerant.
Definitive determination of dietary issues can be accomplished by testing for the physiological effects of specific foods. The ELISA food allergy panel can identify specific foods to which a patient has a reaction. Other testing can determine if there are nutritional deficiencies secondary to diet that may also play a role. Removal of foods causing IgG immune response as measured using the ELISA food panel has been shown to substantially decrease symptoms of IBS in several studies.
There is no evidence that digestion of food or absorption of nutrients is problematic for those with IBS at rates different from those without IBS. However, the very act of eating or drinking can provoke an overreaction of the gastrocolic response in some patients with IBS due to their heightened visceral sensitivity, and this can lead to abdominal pain, diarrhea, and/or constipation.
Several of the most common dietary triggers are well-established by clinical studies at this point; research has shown that IBS patients are hypersensitive to fats and fructose.
It also appears that some foods are more difficult for the gut as evidenced by elevated food-specific IgG4 antibodies being present, while others increase colonic contractions, which may be painful, due to increased visceral sensitivity in IBS sufferers.
Fiber
In patients who do not have diarrhea predominant irritable bowel, soluble fiber at doses of 20 grams per day can reduce overall symptoms but will not reduce pain. The research supporting dietary fiber contains conflicting, small studies that are complicated by the heterogeneity of types of fiber and doses used. The one meta-analysis that controlled for solubility found that only soluble fiber improved global symptoms of irritable bowel and neither type of fiber reduced pain. Positive studies have used 20-30 grams per day of psyllium seed (also called ispaghula husk). One study specifically examined the effect of dose and found that 20 grams of ispaghula husk was better than 10 grams and equivalent to 30 grams per day An uncontrolled study noted increased symptoms with insoluble fibers. It is unclear if these symptoms are truly increased compared to a control group. If the symptoms are increased, it is unclear if these patients were diarrhea predominant (which can be exacerbated by fiber), or if the increase is temporary before benefit occurs.
Medication
Initial treatments
Medications may consist of stool softeners and laxatives in constipation-predominant IBS, and antidiarrheals (e.g., opioid or opioid analogs such as loperamide (Imodium®), diphenoxylate (Lomotil®)) or Codeine in diarrhea-predominant IBS for mild symptoms.
Anti-diarrheal agents
Randomized controlled trials have shown loperamide reduces diarrhea with an inconsistent effect on pain.
Laxatives
Regarding laxatives for patients who do not adequately respond to fiber, osmotic agents (polyethylene glycol, sorbitol, and lactulose) are good choices in order to avoid 'cathartic colon' which has been associated with stimulant laxatives. Among the osmotic laxatives, a randomized controlled trial found greater improvement from 2 sachets (26 grams) of polyethylene glycol (PEG) [MiraLax or GlycoLax] versus or 2 sachets (20 grams) of lactulose . Another randomized controlled trial found no difference between sorbitol and lactulose.
Antispasmodics
The use of antispasmodic drugs (e.g. anticholinergics such as hyoscyamine) may help patients, especially those with cramps or diarrhea. A meta-analysis by the Cochrane Collaboration concludes that if 6 patients are treated with antispasmodics, 1 patient will benefit (number needed to treat = 6). Antispasmodic drugs are also available in combination with tranquilizers or barbiturates, such as Librax® (chlordiazepoxide and clidinium) and Donnatal® (mixed salts of belladonna alkaloids and phenobarbital), respectively. However, the value of the combination therapies is not clear as the role of tranquilizers is not established.
Drugs affecting serotonin (5-HT)
Drugs affecting serotonin (5-HT) in the intestines can help reduce symptoms. Serotonin stimulates the gut motility and so agonists can help constipation predominate irritable bowel while antagonists can help diarrhea predominant irritable bowel:
Agonists
* Tegaserod, a selective 5-HT4 agonist for IBS-C, is available for relieving IBS constipation in women and chronic idiopathic constipation in men and women. ALERT: Tegaserod has been withdrawn from the USA market by the FDA. As of March 30, 2007, the Food and Drug Administration (FDA) has requested that Novartis Pharmaceuticals voluntarily discontinue marketing of Zelnorm (tegaserod) based on the recently identified finding of an increased risk of serious cardiovascular adverse events (heart problems) associated with use of the drug. Novartis has agreed to voluntarily suspend marketing of the drug in the United States. The USA FDA had issued two previous warnings about the serious consequences of Tegaserod. In 2005, Tegaserod was rejected as an IBS medication by the European Union. Tegaserod, marketed as Zelnorm in the United States, was the only agent approved to treat the multiple symptoms of IBS (in women only), including constipation, abdominal pain and bloating. A meta-analysis by the Cochrane Collaboration concludes that if 17 patients are treated with typical doses of tegaserod, 1 patient will benefit (number needed to treat = 17).
* Selective serotonin reuptake inhibitor anti-depressants (SSRIs), because of their serotonergic effect, would seem to help IBS, especially patients who are constipation predominant. Initial crossover studies and randomized controlled trials support this role.
Antagonists
* Alosetron, a selective 5-HT3 antagonist for IBS-D, which is only available for women in the United States under a restricted access program, due to severe risks of side-effects if taken mistakenly by IBS-A or IBS-C sufferers.
* Cilansetron, also a selective 5-HT3 antagonist, is undergoing further clinical studies in Europe for IBS-D sufferers. In 2005, Solvay Pharmaceuticals withdrew Cilansetron from the United States regulatory approval process after receiving a "not approvable" action letter from the FDA requesting additional clinical trials.
Other agents
Anti-depressents include both tricyclic antidepressants (TCAs) and the newer selective serotonin reuptake inhibitors (SSRIs). In addition to improving symptoms via treating any co-existing depression, TCAs have anti-cholinergic actions while SSRIs are serotonergic. Thus in theory, TCAs would best treat diarrhea-predominant IBS while SSRIs would best treat constipation-predominant IBS. A meta-analysis of randomized controlled trials of mainly TCAs found 3 patients have to be treated with TCAs for one patient to improve (number needed to treat = 3). A separate randomized controlled trial found that TCAs are best for patients with diarrhea-predominant IBS. SSRIs are discussed above under 'Drugs affecting serotonin'.
Recent studies have suggested that rifaximin, a non-absorbable antibiotic, can be used as an effective treatment for abdominal bloating and flatulence, giving more credibility to the potential role of bacterial overgrowth in some patients with IBS.
A double-blind, randomized, placebo-controlled trial compared the multi-herbal extract Iberogast versus placebo in the treatment of all three forms of irritable bowel syndrome. This multi-target phytopharmaceutical was found to be significantly superior to placebo via both an abdominal pain scale (p value = 0.0009) and an IBS symptom score (p value = 0.001) after four weeks of treatment.
Enteric coated peppermint oil capsules has been advocated for IBS symptoms in adults and children; however, results from trials have been inconsistent. Peppermint may exacerbate gastroesophageal reflux disease.
For severe diarrhea-predominant IBS, more potent opioids may be used, such as codeine or propoxyphene (Darvon®); refractory cases may even be treated with paregoric, or, more rarely, deodorized tincture of opium or morphine sulfate. The use of opioids remains controversial due to the lack of evidence supporting their benefit and the potential risk of tolerance, physical dependence and psychological dependence (addiction).
Cannabis has theoretical support for its role, but has not been subject of clinical studies. Although illegal in the United States, it has been prescribed to patients in nations such as Canada. Some of the argued benefits of cannabis are the reduction of pain and nausea, appetite stimulation, and assisting in falling asleep.
New Drugs Under Development
New drugs are currently under development for IBS and offer opportunities for gaining access to drug alternatives to those listed above. Trying new drugs for IBS often involves joining a clinical trial and trying an investigational medicine for a period of time to determine if it is effective in treating your IBS symptoms while monitoring the drug for safety and tolerance. Investigational drugs are not yet approved by the FDA but if you are accepted into the trial and respond well you may be given the opportunity to continue using the drug even after the clinical trial is complete. If you are interested in participating in clinical trials for IBS you should ask your doctor about existing clinical trials opportunities or ask to be referred to a GI specialist that would have clinical trials available. You may also use the various resources on the bottom of the page to learn more about IBS clinical trials.
Psychotherapy and hypnotherapy
There is a strong brain-gut component to IBS, and cognitive therapy may improve symptoms in a proportion of patients in conjunction with antidepressants . In a randomized controlled trial of referred patients, cognitive behavioral therapy helped even though patients in this study did not have any psychiatric diagnoses.
Gut-directed or gut-specific hypnotherapy or self-hypnosis is one of the most promising areas of IBS treatment. Current research shows that symptom reduction/elimination from IBS hypnotherapy can last at least five years.
Alternative treatments
Probiotics
Probiotics are generally accepted to be potentially beneficial strains of bacteria and yeast, often found in the human gut. One research study has shown a clear link between the ingestion of Lactobacillus plantarum LP299V and sufferers of IBS who reported resolution of their abdominal pain [64]. Another study showed the utility of B. infantis 35625, a strain of Bifidobacteria in normalizing bowel movement frequency in sufferers of IBS. Some practitioners of Integrative Medicine, now recommend a strain of Lactobacillus known commonly as "LGG" after its discoverers Gorbach and Goldin. This strain in particular has shown an ability to endure the acidic environment of the stomach and survive until presentation to the intestinal tract.
A prospective placebo-controlled study found patients with diarrhea predominant IBS taking Saccharomyces boulardii, a probiotic yeast, had a significant reduction on the number and improvement in consistency of bowel movements.
Acupuncture
Many sufferers of IBS seek relief using Acupuncture, a component of Traditional Chinese Medicine. The meta-analysis by the Cochrane Collaboration concluded 'Most of the trials included in this review were of poor quality and were heterogeneous in terms of interventions, controls, and outcomes measured. With the exception of one outcome in common between two trials, data were not combined. Therefore, it is still inconclusive whether acupuncture is more effective than sham acupuncture or other interventions for treating IBS'. One practitioner of Tradtional Chinese Medicine asserts that IBS has become a bit of a "garbage diagnosis" for some medical practitioners. Traditional Chinese Medicine does not recognize the Western diagnosis of IBS per se, as the named condition has no definitive single test for diagnosis, clear cause, or cure. Traditional Chinese Medicine approaches IBS on an individual symptom-by-symptom basis, rather than recognizing a standard "IBS" diagnosis, which then warrants a blanket "IBS" treatment . According to the National Institutes of Health, "Preclinical studies have documented acupuncture's effects, but they have not been able to fully explain how acupuncture works within the framework of the Western system of medicine that is commonly practiced in the United States."
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Important notice:
The content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other
qualified health provider with any questions you may have regarding a medical condition.
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