Irritable bowel syndrome is a common, recurrent chronic gastrointestinal disorder for which there is no single drug that achieves good treatment outcomes and patients’ quality of life is often negatively affected. Recently, the British Society of Gastroenterology published updated guidelines for the diagnosis and treatment of irritable bowel syndrome. The guidelines cover dietary and psychological treatment, and primary care.
Defecation habits (diarrhea or constipation) is a valid grading scheme. If diarrhea is the main feature, further testing is rarely needed, although other warning signs suggest that further testing may be needed. Careful attention to the medical history is essential for diagnosis. Typically, abdominal pain or discomfort usually resolves with defecation and is associated with changes in stool shape (which usually becomes loose) and frequency.
Associated features may also help confirm the diagnosis, including frequent medically unspecified symptoms, somatic symptoms, and a history of anxiety or depression. Psychological assessment of current anxiety and depressive symptoms is also important.
The presence of warning symptoms, even if nonspecific, requires further investigation. These include: age >50 years, symptoms lasting less than 6 months), weight loss, nocturnal symptoms, family history of colon cancer, rectal bleeding, anemia, and recent antibiotic use. Further testing may be effective when these warning symptoms are present. Also, before further testing, the physician should tell the patient that the most likely diagnosis is irritable bowel syndrome, and these tests can be used to rule out celiac disease and inflammatory bowel disease. Validated tests include a complete blood count, red blood cell sedimentation rate and human endomysial antibody testing.
Many patients are concerned that their symptoms may be a reflection of a serious illness. Patients should be made to confide in their anxiety and have a discussion of their condition during the consultation. Because irritable bowel syndrome is often associated with adverse psychological features and physical symptoms, it can be well managed by grasping the patient’s psychology and by explaining his or her symptoms in depth. Without denying the importance of symptoms, giving patients a definitive diagnosis and reassuring them of the good prognosis of IBS can improve outcomes. Treatment of the associated anxiety and depression often improves other symptoms such as bowel.
Irritable bowel syndrome has more than a single presentation and has many treatment options, each of which benefits only a small percentage of people. Dietary control should be based on a complete dietary history, while controlling each nutrient so that it is not overconsumed. If intake of lactose, wheat and/or insoluble fiber is higher than the general population, then reducing intake of these foods may be helpful. Psychotherapy should be the first line of treatment if anxiety, panic, and depression become the main symptoms. Results from randomized placebo-controlled clinical trials have shown that cognitive behavioral therapy and psychodynamic and interpersonal psychotherapy improve coping for patients for whom other approaches have not been effective, while hypnotherapy improves all symptoms. In addition, relaxation therapy has been beneficial.
In terms of medication, antitussives are safe, but show only a small improvement compared to placebo. Soluble fiber supplementation improves constipation symptoms, while bran and other insoluble fibers may make them worse. Lopamid is effective in relieving urgent and frequent symptoms, but has the potential to exacerbate abdominal pain and discomfort. Antispasmodics and tricyclic antidepressants improve pain, while ovalleaf plantain improves pain along with bowel habits. While 5HT3 antagonists improve systemic symptoms, diarrhea and pain, a few may cause colitis. 5HT4 antagonists improve systemic symptoms, constipation and bloating, while selective 5HT reuptake inhibitors improve systemic symptoms.