Patients with irritable bowel syndrome usually present with the following symptoms:
Altered Bowel Habits: Both constipation and diarrhea can occur in the patients suffering from irritable bowel syndrome, however, one of them may predominate in a single patient. Those with constipation pass hard, infrequent stools. In contrast, those with diarrhea have low volume stools but with frequent defecation.
Abdominal distension: Bloating and gas causes abdominal distention in these patients. Abdominal distention typically worsens during the day.
Other symptoms: Patients of irritable bowel syndrome may have sexual dysfunction, urinary frequency, urgency and dysuria may be present. Other non-specific symptoms include nausea, vomiting and heart burn.
Entire Body System
Studies of IBS among patients with chronic fatigue syndrome have reported a prevalence ranging from 35-92%. The prevalence of IBS among patients with chronic fatigue syndrome is reported to be 14%. [ncbi.nlm.nih.gov]
In the mid 19th century Beard, 55 an American neurologist, published a paper on "neurasthenia", a term he used to describe individuals with unexplained chronic fatigue and lassitude (nervous exhaustion). [doi.org]
These symptoms are similar to other symptom complexes like chronic fatigue and the so called ‘candida syndrome’, and many seek help from alternative medicine. [citeseerx.ist.psu.edu]
Asian foods high in FODMAPs include Korean foods (kimchi, doenjang, ssamjang, and mandu), Japanese foods (gyozas), Thai foods (tom yum soup and some curry paste), Chinese foods (dim sum, wonton, man tou, red been sweet soup, and green bean soup), and Vietnamese [doi.org]
- Abdominal Pain
The incidence of cholecystectomy was higher in irritable bowel syndrome and abdominal pain and normal bowel groups than in controls and altered bowel and no abdominal pain group. [ncbi.nlm.nih.gov]
Saito, James Moriarty and Cathy Schleck, A case-control comparison of direct healthcare-provider medical costs of chronic idiopathic constipation and irritable bowel syndrome with constipation in a community-based cohort, Journal of Medical Economics, [doi.org]
Mean annual direct health care costs were 5049 for IBS, 6140 for diarrhoea, 7522 for constipation and 7646 for abdominal pain. [ncbi.nlm.nih.gov]
Some people with the disorder have constipation. Some have diarrhea. Some go back and forth between constipation and diarrhea. Although ibs can cause a great deal of discomfort, it does not harm the intestines. [icd9data.com]
Convert to ICD-10-CM : 564.1 converts approximately to: 2015/16 ICD-10-CM K58.9 Irritable bowel syndrome without diarrhea Approximate Synonyms Colon spasm Colon spasm w diarrhea Colon spasm with diarrhea Colonospasm Irritable bowel syndrome w diarrhea [icd9data.com]
Prifinium bromide's efficacy in the treatment of abnormal bowel movements was most evident in patients with diarrhea and slightly less evident in patients with alternation of diarrhea and constipation, and in constipated patients. [ncbi.nlm.nih.gov]
People with IBS may have diarrhea, constipation, or both. Some people with IBS have only diarrhea or only constipation. Some people have symptoms of both or have diarrhea sometimes and constipation other times. [web.archive.org]
People with IBS may go back and forth between having constipation and diarrhea or have or mostly have one or the other. If you have IBS with diarrhea, you will have frequent, loose, watery stools. [nlm.nih.gov]
Ispaghula therapy resulted in improvement in global symptoms and satisfying bowel movements (P less than 0.001) but produced no change in abdominal pain or flatulence. [ncbi.nlm.nih.gov]
A person should also see a doctor if their symptoms get progressively worse, stools are pale, bulky, very offensive smelling and difficult to flush away (this may indicate a problem with absorbing fat), or if they are concerned about their symptoms. [mydr.com.au]
Metcalfe DD (2000) Differential diagnosis of the patient with unexplained flushing/anaphylaxis. Allergy Asthma Proc 21(1):21–24 CrossRef PubMed Google Scholar 31. Lafont E et al (2014) Causes and diffential diagnosis of flush. [doi.org]
Mannix, Menstrual-Related Pain Conditions: Dysmenorrhea and Migraine, Journal of Women's Health, 17, 5, (879), (2008). B. [doi.org]
[…] that 26 percent of children with recurrent abdominal pain were diagnosed with IBS, making it a common reason for school absenteeism. 7 Seventy percent of patients with IBS are women; 48 to 79 percent of patients with chronic pelvic pain, dyspareunia, dysmenorrhea [web.archive.org]
[…] circadian rhythm, history of abuse, anxiety, and depression   It has also been seen with many other pain syndromes and functional disorders such as fibromyalgia, chronic fatigue syndrome, tempromandibular joint disorder, chronic pelvic pain, and dysmenorrhea [physio-pedia.com]
Headache. 2014 Nov-Dec;54(10):1644-6. doi: 10.1111/head.12429. Epub 2014 Jul 18. Author information 1 Montefiore Headache Center, Department of Neurology, Albert Einstein College of Medicine, Bronx, NY, USA. [ncbi.nlm.nih.gov]
Abdominal pain (OR 1.01; 95% CI: 0.98–1.03; P 0.05), nausea (OR 1.00; 95% CI: 0.98–1.02; P 0.05), vomiting (OR: 0.99; 95% CI: 0.98–1.01; P 0.05), and headache (OR 1.01; 95% CI: 0.98–1.03; P 0.05) did not differ significantly between the rifaximin [doi.org]
The diagnosis of irritable bowel syndrome is difficult. It was once considered a diagnosis of exclusion; however, this belief is no longer valid. The diagnosis is based on history, general physical examination, laboratory investigations and radiographic studies .
The findings in history and general physical examination often indicate iron deficiency anemia. Weight loss is also a common feature. A family history of certain gastrointestinal disorders including celiac disease, inflammatory bowel disease and colorectal carcinoma is often present.
The following investigations are necessary to establish the diagnosis with certainty.
Blood studies include:
- Complete blood count: This is used to rule out anemia, inflammation and infection.
- Electrolyte levels: They can demonstrate electrolyte imbalance and dehydration in metabolic disorders.
History-specific examinations in irritable bowel syndrome include:
- Hydrogen breath test
This test excludes bacterial overgrowth in patients presenting with diarrhea and the complaints of lactose and fructose intolerance.
- Tissue transglutaminase antibody test
- Thyroid function test
- Erythrocyte sedimentation rate
- C-reactive protein
History specific imaging studies
These studies include:
- Barium studies of the upper gastrointestinal tract are performed to detect any obstruction or inflammatory condition (such as Crohn’s disease)
- Abdominal CT scan is also required to look for tumors, obstruction and pancreatic diseases.
History specific procedures
History specific procedures include:
Over the years, the unexplained gastrointestinal symptoms of the irritable bowel syndrome have been described in various terms, including mucous colitis, spastic colitis, nervous colon, and irritable colon. [dx.doi.org]
Isgar B, Harman M, Kaye MD, Whorwell PJ: Symptoms of irritable bowel syndrome in ulcerative colitis in remission. Gut 24:190-192, 1983 Google Scholar 8. [doi.org]
The management of irritable bowel syndrome includes dietary measures and psychological support.
The dietary measures that are recommended in the patients suffering from irritable bowel syndrome are listed below.
- Fiber supplementation is essential to improve symptoms of constipation and diarrhea
- Polycarbophil compounds (Fibercon) are highly recommended
- Adequate water intake is necessary
- Caffeine avoidance is recommended to limit anxiety
- Legumes should be avoided to limit bloating
- Lactose and/or fructose intake should be restricted
- Gluten free diet is also beneficial 
A number of other drugs have a beneficial role in the management of irritable bowel syndrome. These drugs are:
The life expectancy in the patients suffering from this disease is the same as that in healthy population. Female patients may have an increased risk of ectopic pregnancies and miscarriages; however, there is no association with stillbirth.
There is no specific cause for the development of irritable bowel syndrome.
Enteric infection may lead to the development of irritable bowel syndrome in the majority of the cases. A study demonstrated the prevalence of irritable bowel syndrome in patients suffering from enteritis caused by Giardia lamblia to be as high as 46.1% as opposed to only 14% in the controls .
Since irritable bowel syndrome is more common in families, genetic factors may also play a predisposing role. Other predisposing factors include inflammatory processes like food intolerance, lack of dietary fibers in the diet and alterations in the gut microbiota  . Anxiety, excessive worry and sexual or physical abuse are also contributing factors.
Irritable bowel syndrome affects both men and women and occurs most commonly in individuals between 30 and 50 years of age. In Western countries, female-to-male ratio is 2:1. According to the epidemiological data from the United States, around 5 to 9% of men and 14 to 24% of women are affected.
The global incidence of irritable bowel syndrome is estimated to be 1-2% annually while the prevalence is around 10 to 15%. Prevalence is similar in white and black population but lower in Hispanics.
The pathogenesis of irritable bowel syndrome includes several components which are further explained below:
Altered gastrointestinal motility: The electrical activity of the bowel is disturbed which causes altered gastrointestinal motility of both the small and large gut.
Visceral hyperalgesia: There is hypersensitivity of the small and large gut is increased, particularly with rapid distention. This is more common in women and in the patients in whom this disease is predominantly characterized by diarrhea.
Psychopathology: There is no well-known association between psychopathic disturbances and the pathogenesis of irritable bowel syndrome. Yet, patients under medical care are highly prone to the development of depression, panic and anxiety. These patients usually present with history of suicidal attempts .
Microscopic inflammation: Inflammation of both the colon and the small bowel have been demonstrated in the patients suffering from irritable bowel syndrome . The number of lymphocytes and enteroendocrine cells in the bowel is also increased. The latter secrete serotonin, the action of which causes diarrhea.
Irritable bowel syndrome can be prevented by ensuring proper hygiene. The use of high fiber diet is also helpful.
Irritable bowel syndrome (IBS) is a chronic gastrointestinal disorder that is characterized by abdominal pain, altered bowel habits (diarrhea, constipation or both) without any underlying obvious pathologic change in the small and large gut. The disease is not life threatening condition but it can disrupt the quality of life.
- Wensaas KA, Langeland N, Hanevik K, Morch K, Eide GE, Rortveit G. Irritable bowel syndrome and chronic fatigue 3 years after acute giardiasis: historic cohort study. Gut. Feb 2012;61(2):214-219.
- Shepherd SJ, Parker FC, Muir JG, Gibson PR. Dietary triggers of abdominal symptoms in patients with irritable bowel syndrome: randomized placebo-controlled evidence. Clinical gastroenterology and hepatology : the official clinical practice journal of the American Gastroenterological Association. Jul 2008;6(7):765-771.
- Kassinen A, Krogius-Kurikka L, Makivuokko H, et al. The fecal microbiota of irritable bowel syndrome patients differs significantly from that of healthy subjects. Gastroenterology. Jul 2007;133(1):24-33.
- Miller V, Hopkins L, Whorwell PJ. Suicidal ideation in patients with irritable bowel syndrome. Clinical gastroenterology and hepatology : the official clinical practice journal of the American Gastroenterological Association. Dec 2004;2(12):1064-1068.
- Bercik P, Verdu EF, Collins SM. Is irritable bowel syndrome a low-grade inflammatory bowel disease? Gastroenterology clinics of North America. Jun 2005;34(2):235-245, vi-vii.
- Spiegel BM, Farid M, Esrailian E, Talley J, Chang L. Is irritable bowel syndrome a diagnosis of exclusion?: a survey of primary care providers, gastroenterologists, and IBS experts. The American journal of gastroenterology. Apr 2010;105(4):848-858.
American College of Gastroenterology Task Force on Irritable Bowel S,
- Brandt LJ, Chey WD, et al. An evidence-based position statement on the management of irritable bowel syndrome. The American journal of gastroenterology. Jan 2009;104 Suppl 1:S1-35.
- Biesiekierski J, Newnham, ED, Irving, PM, Barrett, JS, Haines, M, Doecke, JD, et al. Gluten causes gastrointestinal symptoms in subjects without celiac disease. The American journal of gastroenterology. 2011;106(3):508-514.
- Thumshirn M, Coulie B, Camilleri M, Zinsmeister AR, Burton DD, Van Dyke C. Effects of alosetron on gastrointestinal transit time and rectal sensation in patients with irritable bowel syndrome. Alimentary pharmacology & therapeutics. Jul 2000;14(7):869-878.
- Bardhan KD, Bodemar G, Geldof H, et al. A double-blind, randomized, placebo-controlled dose-ranging study to evaluate the efficacy of alosetron in the treatment of irritable bowel syndrome. Alimentary pharmacology & therapeutics. Jan 2000;14(1):23-34.