The low down on Irritable Bowel Syndrome

Introduction: Irritable bowel syndrome (IBS) is the most common referral to a gastroenterologist.The prevalence is between 14% to 24% in women and 5% to 19% in men in the US and Britain. It cost US $1.6 billion in 1998 mostly in medication and diagnostic tests.

While volumes have been written, which make stimulating reading, on the pathogenesis of IBS namely brain gut neural dysfunction, visceral hypersensitivity, sympathetic and parasympathetic imbalance, role of gut infection etc., purpose of this review is to focus on practical management of IBS.

Diagnosis could be made on the basis of Rome II clinical criteria which states IBS consists of abdominal pain or discomfort lasting any 12 weeks in the preceding 12 months which has two of the following features e.g., a) relieved by defaecation, b) onset associated with a change in stool frequency and c) onset associated with a change in stool form (appearance). This criteria is deemed to be sufficient if patient does not have “Red flags” /alarm symptoms when investigations and endoscopy would be warranted (1).

Red flags/ Alarm symptoms: These constitute weight loss, anaemia, occult blood in stool, travel history to areas with endemic parasites, night time symptoms, onset of symptoms after 50yr of age, family history of bowel cancer or inflammatory bowel disease, arthritis or dermatitis and signs of malabsorption and thyroid dysfunction.

Endoscopy ( gastroscopy and or colonoscopy): should be considered when a patient have “Red flags”, when a patient has failed to respond to treatment for IBS over 1-2 months, and when a patient has expressed significant anxiety over the possibility of organic disease (2).

Lactose Hydrogen breath test: could be undertaken also given that lactose intolerance is found in 25% of IBS patients which is about the same as found in the general population.

TSH: Thyroid dysfunction is found in 6 % of IBS compared to 5-9% prevalence in the general population.

Coeliac antibodies: should also be considered in diarrhoea type IBS.

Anorectal manometry: may be required to differentiate between constipation predominant IBS and outlet constipation and Levator Ani syndrome.

Management of IBS:

There are three types of IBS generally recognised.

Diarrhoea predominant IBS

These patients are recognized by their morning multiple loose bowel actions with cramps and a sense of incomplete defaecation. Bloating may or may not be a feature. Investigations should include stool microscopy, routine blood tests, coeliac antibodies, TSH and possibly lactose H2 breath test. If these tests are normal, I start with a low dose of fibre e.g., Metamucil one spoon daily after food. This more often than not firms up bowel actions and reduces frequency. Failing above , tricyclic antidepressants e.g., amitriptyline at a small dose e.g., 25 mg nocte or antispasmodics e.g., mebeverine with prn loperamide would work. On the other hand, if stool microscopy demonstrates red cell and or white cells then a colonoscopy would be required.

Constipation predominant IBS: These patients are recognized by their constipation, bloating and lower abdominal pain. Investigation should include an AXR to confirm faecal loading, routine blood tests and TSH. Initial treatment should be started with sterculia (normafibe) which, unlike most fibres rarely aggravate the bloating. Failing, combination of sterculia and frangula (granacol/ normacolo plus) could be used with or without lactulose. Bloating respond to prokinetic agents e.g., tagaseroid (Zelmac) 3mg bd ac or metoclopramide (maxolon) 5mg tds ac. Failing satisfactory response in a month, a colonoscopy should be considered.

Alternating constipation and diarrhoea type IBS: Typically these patients describe no bowel action for 2-3 days with progressive bloating followed by a spell of 4-5 episodes of diarrhoea over a day. Then the cycle repeats itself. Underlying problem is progressive constipation with subsequent clearance. Thus, the investigations are those of AXR during the constipation phase, TSH, routine blood tests and stool microscopy during the diarrhoeal phase of the cycle. Treatment initially with fibre e.g., sterculia/nucolox regularly over several weeks could avert the diarrhoeal phase from manifesting altogether. Tagaseroid(zelmac) / metoclopramide may be needed for the bloating. Likewise antispamodics are rarely required for the diarrhoeal phase once constipation has been prevented from developing. Failing adequate response, a colonoscopy should be considered.

Other facets of IBS management: Overall benign nature of the condition should be emphasized. Regular diet should be encouraged without missing meals. Intake of fruits and cruciferous vegetables should be encouraged. If you are skilled( I am not in this regard), consider taking history of abuse (physical or sexual). Some 40% of IBS patients have history of abuse and 30% of these patients never sought any help. Psychotherapy is likely to help the symptoms.


1.Chey WD et al.Clinical Update 2004,11:1-4.

2.Olden KW.Gastroenterology 2002,122:1701-1714.

Editorial: Gastroenterologist’s Perspective on Clopidogrel

In the hospital setting, I am having to deal with Clopidogrel related GI bleeding, on an average, once a fortnight mostly in the setting of combination of Clopidogrel and Aspirin. While the combination of Clopridogrel and Aspirin may be better than Clopidogrel or Aspirin alone for the prevention of occlusion of the coronary or other vascular stents, the two drugs used together is a morbid combination from Gastroenterologist’s point of view. Aspirin causes the ulcer and Clopidogrel ensures continued bleeding. On an average, these patients require 8-9 units of transfusion as well as platelet transfusion before they stop bleeding over 2-3 days. While the risk/benefit ratio for the combination of Aspirin and Clopidogrel will see more debate in the future and would certainly be the subject of rigorous interrogation with scientific studies, I urge, in the meantime, all patients requiring open access endoscopic procedures, which may involve biopsy and polypectomy , discontinue their clopidgrel at least 10 days before their procedure in consultation with their general practitioner /cardiologist/ vascular surgeon. Serious bleeding has been reported when such minor procedure such as endoscopic biopsy was taken. I am happy to discuss these issues on the phone or undertake a pre-procedure consultation with these patients.

Bhaskar Chakravarty

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