Failure of the terminal ileum to reabsorb bile salts may result from Crohn's disease, or ileal resection, and it occurs in many patients with microscopic colitis. Bile salts in the colon cause diarrhoea which is relieved by colestyramine. The dose required is titrated against symptoms, starting with 8 g bd. Colestyramine can also bind to many drugs and reduce their bioavailability (see p. 131).
IRRITABLE BOWEL SYNDROME (IBS)
This condition affects 20% of the population and is the commonest reason for referral to a gastroenterologist. It is manifested by a variety of gastrointestinal symptoms including disordered bowel habit (constipation, diarrhoea or both), abdominal pain and bloating. Upper gastrointestinal symptoms manifest as nonulcer dyspepsia (see Chapter 31). All these symptoms occur in the absence of demonstrable pathology in the gastrointestinal tract, although patients with IBS often have abnormalities of gut motility. Another feature of the condition is visceral hypersensitivity; patients with IBS have lower thresholds for pain from colonic distension induced by inflating balloons placed in the bowel. A proportion of patients develop their IBS symptoms after an episode of gastroenteritis and in many emotional stress is an important precipitating factor. Associated psychopathology, with anxiety and sometimes depression, are common.
The mainstay of treatment, after investigation when appropriate, is to reassure the patient of the entirely benign nature of the disorder and the good prognosis. Those with predominant constipation should be encouraged to increase the fluid and fibre content of their diet. Unprocessed bran can lead to troublesome bloating and wind and a bulking agent such as ispaghula husk is often better tolerated.
Diarrhoea can be treated with an antimotility drug such as loperamide, the dose being adjusted to symptoms. Codeine phosphate is effective although it may cause sedation.
Antispasmodics (see below) are given for abdominal pain, although there is little objective evidence for their efficacy from controlled clinical trials. The generation of evidence is complicated by the variable nature of IBS symptoms, the patients who suffer from them, and the high rate of placebo response in this condition. There are two main classes of antispasmodic, the antimuscarinic drugs and drugs which are direct smooth muscle relaxants.
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Did you ever think feeling angry and irritable could be a symptom of constipation? A horrible fullness and pressing sharp pains against the bladders can’t help but affect your mood. Sometimes you just want everyone to leave you alone and sleep to escape the pain. It is virtually impossible to be constipated and keep a sunny disposition. Follow the steps in this guide to alleviate constipation and lead a happier healthy life.