www.idosr.org Bethany ©IDOSR PUBLICATIONS International Digital Organization for Scientific Research ISSN: 2579-0730 IDOSR JOURNAL OF BIOLOGY, CHEMISTRY AND PHARMACY 4(1)15-22, 2020.

Overview of (IBS)

Bethany Hoey

School of Nursing, Queensland University of Technology (QUT), Australia. ABSTRACT This article is the overview of irritable bowel syndrome (IBS). Irritable bowel syndrome (IBS) is a group of symptoms including and changes in the pattern of bowel movements without any evidence of underlying damage. These symptoms occur over a long time, often years. Irritable bowel syndrome (IBS) affects between 6–18% of people worldwide. This condition involves changes in frequency or form of bowel movements and lower abdominal pain Diet, stress, poor sleep and changes in gut bacteria may all trigger symptoms. The precise cause of IBS isn't known. Finding ways to deal with stress may help prevent or ease symptoms of IBS. There's no test to definitively diagnose IBS. Your doctor is likely to start with a complete medical history, physical exam and tests to rule out other conditions. IBS is a chronic functional disorder of the with symptoms of abdominal pain and altered bowel habits that include , constipation, or both. Patients who suffer from IBS often have an impaired quality of life. IBS affects 10% to 20% of the general population, but these percentages are likely underestimated, since only a small portion of patients with IBS symptoms seek medical attention. Keywords: Overview, irritable, bowel, syndrome and IBS.

INTRODUCTION Irritable bowel syndrome (IBS) is a group in the absence of worrisome features and of symptoms including abdominal pain once other potential conditions have been and changes in the pattern of bowel ruled out. Worrisome features include movements without any evidence of onset at greater than 50 years of age, underlying damage. These symptoms weight loss, blood in the stool, or a family occur over a long time, often years. It has history of inflammatory bowel disease. been classified into four main types Other conditions that may present depending on whether diarrhea is similarly include celiac disease, common, constipation is common, both microscopic colitis, inflammatory bowel are common, or neither occurs very often disease, bile acid malabsorption, and (IBS-D, IBS-C, IBS-M, or IBS-U respectively). colon cancer [2]. IBS negatively affects quality of life and There is no known cure for IBS. Treatment may result in missed school or work.[9] is carried out to improve symptoms. This Disorders such as anxiety, major may include dietary changes, medication, depression, and chronic fatigue syndrome , and counseling. Dietary are common among people with IBS [1]. measures include increasing soluble fiber The causes of IBS are not clear. Theories intake, a gluten-free diet, or a short-term include combinations of gut–brain axis diet low in fermentable oligosaccharides, problems, gut motility disorders, pain disaccharides, monosaccharides, and sensitivity, including small polyols () [3]. The medication intestinal bacterial overgrowth, may be used to help with neurotransmitters, genetic factors, and diarrhea while may be used to food sensitivity. Onset may be triggered help with constipation. Antidepressants by an intestinal , or stressful life may improve overall symptoms and event. IBS is a functional gastrointestinal reduce pain. Patient education and a good disorder. Diagnosis is based on symptoms doctor–patient relationship are an

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www.idosr.org Bethany important part of care. About 10 to 15% of medication specifically proven to ease IBS people in the developed world are pain. believed to be affected by IBS. It is Diarrhea estimated that 45% of people globally are Diarrhea-predominant IBS is one of the affected by IBS. It is more common in three main types of the disorder. It South America and less common in affects roughly one-third of patients with Southeast Asia [4]. It is twice as common IBS. A study of 200 adults found that in women as men and typically occurs those with diarrhea-predominant IBS had, before age 45. The condition appears to on average, 12 bowel movements weekly become less common with age. IBS does more than twice the amount of adults not affect life expectancy or lead to other without IBS. Accelerated bowel transit in serious diseases. The first description of IBS can also result in a sudden, immediate the condition was in 1820 while the urge to have a bowel movement. Some current term irritable bowel syndrome patients describe this as a significant came into use in 1944. source of stress, even avoiding some Signs and Symptoms of Irritable Bowel social situations for fear of a sudden Syndrome (IBS) onset of diarrhea. Additionally, stool in Irritable bowel syndrome (IBS) affects the diarrhea-predominant type tends to between 6–18% of people worldwide. This be loose and watery and may contain condition involves changes in frequency mucus [8]. or form of bowel movements and lower Constipation abdominal pain Diet, stress, poor sleep Although it seems counterintuitive, IBS and changes in gut bacteria may all can cause constipation as well as trigger symptoms. However, triggers are diarrhea. Constipation-predominant IBS is different for each person, making it the most common type, affecting nearly difficult to name specific foods or 50% of people with IBS. Altered stressors that everyone with the disorder communication between the brain and should avoid [5]. This article will discuss bowel may speed up or slow down the the most common symptoms of IBS and normal transit time of stool. When transit what to do if you suspect you have it. time slows, the bowel absorbs more water Pain and Cramping from stool, and it becomes more difficult Abdominal pain is the most common to pass. Constipation is defined as having symptom and a key factor in diagnosis. fewer than three bowel movements per Normally, your gut and brain work week. ―Functional‖ constipation describes together to control digestion. This chronic constipation not explained by happens via hormones, nerves and signals another disease. It is not related to IBS released by the good bacteria that live in and is very common. Functional your gut. In IBS, these cooperative signals constipation differs from IBS in that it is become distorted, leading to generally not painful. In contrast, uncoordinated and painful tension in the constipation in IBS includes abdominal muscles of the digestive tract [7]. This pain that eases with bowel movements. pain usually occurs in the lower abdomen Constipation in IBS also often causes a or the entire abdomen but is less likely to sensation of an incomplete bowel be in the upper abdomen alone. Pain movement. This leads to unnecessary typically decreases following a bowel straining. Along with the usual treatments movement. Diet modifications, such as a for IBS, exercise, drinking more water, diet low in FODMAPs, may improve pain eating soluble fiber, taking probiotics and and other symptoms Other treatments the limited use of laxatives may help [9]. include bowel relaxants like Alternating Constipation and Diarrhea oil, cognitive behavior therapy and Mixed or alternating constipation and hypnotherapy For pain that doesn’t diarrhea affects about 20% of patients respond to these changes, a with IBS. Diarrhea and constipation in IBS gastroenterologist can help you find a involve chronic, recurring abdominal pain. Pain is the most important clue that

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www.idosr.org Bethany changes in bowel movements are not Fatigue and Difficulty Sleeping related to diet or common, mild Over half of people with IBS report infections. This type of IBS tends to be fatigue. In one study, 160 adults more severe than the others with more diagnosed with IBS described low stamina frequent and intense symptoms. The that limited physical exertion in work, symptoms of mixed IBS also vary more leisure and social interactions. from one person to another. Therefore, Another study of 85 adults found that the this condition requires an individualized intensity of their symptoms predicted the treatment approach rather than ―one-size- severity of fatigue. IBS is also related to fits-all‖ recommendations [10]. insomnia, which includes difficulty falling Changes in Bowel Movements asleep, waking frequently and feeling Slow-moving stool in the intestine often unrested in the morning. In a study of becomes dehydrated as the intestine 112 adults with IBS, 13% reported absorbs water. In turn, this creates hard poor sleep quality. Another study of 50 stool, which can exacerbate symptoms of men and women found that those with IBS constipation. Prompt movement of stool slept about an hour longer yet felt less through the intestine leaves little time for refreshed in the morning than those absorption of water and results in the without IBS [12]. Interestingly, poor sleep loose stools characteristic of diarrhea. IBS predicts more severe gastrointestinal can also cause mucus to accumulate in symptoms the following day. stool, which is not usually associated with Anxiety and Depression other causes of constipation. Blood in IBS is linked to anxiety and depression, as stool may be a sign of another, potentially well. It’s unclear whether IBS symptoms serious medical condition and deserves a are an expression of mental stress or visit to your doctor. Blood in stool may whether the stress of living with IBS appear red but often appears very dark or makes people more prone to black with a tarry consistency [11]. psychological difficulties [13]. Whichever Gas and Bloating comes first, anxiety and digestive IBS Altered digestion in IBS leads to more gas symptoms reinforce one another in a production in the gut. This can cause vicious cycle. In a large study of 94,000 bloating, which is uncomfortable. Many men and women, people with IBS were with IBS identify bloating as one of the over 50% more likely to have an anxiety most persistent and nagging symptoms of disorder and over 70% more likely to have the disorder. In a study of 337 IBS a mood disorder, such as depression. patients, 83% reported bloating and Another study compared levels of the cramping. Both symptoms were more stress hormone in patients with common in women and in constipation- and without IBS. Given a public speaking predominant IBS or mixed types of IBS. task, those with IBS experienced greater Food Intolerance changes in cortisol, suggesting greater Up to 70% of individuals with IBS report stress levels (35). that particular foods trigger symptoms. Causes of Irritable Bowel Syndrome (IBS) Two-thirds of people with IBS actively The precise cause of IBS isn't known. avoid certain foods. Sometimes these Factors that appear to play a role include: individuals exclude multiple foods from  Muscle contractions in the the diet. Why these foods trigger intestine. The walls of the symptoms is unclear. These food intestines are lined with layers of intolerances are not allergies, and trigger muscle that contract as they move foods don’t cause measurable differences food through your digestive tract. in digestion. While trigger foods are Contractions that are stronger and different for everyone, some common last longer than normal can cause ones include gas-producing foods, such gas, bloating and diarrhea. Weak as FODMAPs, as well as lactose and intestinal contractions can slow gluten. food passage and lead to hard, dry stools.

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www.idosr.org Bethany  Nervous system. Abnormalities in in your feet, then concentrate on the nerves in your digestive slowly letting all of the tension go system may cause you to [14]. Next, tighten and relax your experience greater than normal calves. Continue until the muscles in discomfort when your abdomen your body, including those in your stretches from gas or stool. Poorly eyes and scalp, are relaxed. coordinated signals between the  Mindfulness training. This stress- brain and the intestines can cause reduction technique helps you focus your body to overreact to changes on being in the moment and letting that normally occur in the go of worries and distractions. digestive process, resulting in Risk factors pain, diarrhea or constipation. Many people have occasional signs and  Inflammation in the intestines. symptoms of IBS. But you're more likely Some people with IBS have an to have the syndrome if you: increased number of immune-  Are young. IBS occurs more system cells in their intestines. frequently in people under age 50. This immune-system response is  Are female. In the United States, IBS associated with pain and diarrhea. is more common among women.  Severe infection. IBS can develop Estrogen therapy before or after after a severe bout of diarrhea menopause also is a risk factor for (gastroenteritis) caused by bacteria IBS. or a virus. IBS might also be  Have a family history of IBS. Genes associated with a surplus of may play a role, as may shared bacteria in the intestines (bacterial factors in a family's environment or overgrowth). a combination of genes and  Changes in bacteria in the gut environment. (microflora). Microflora are the  Have a mental health "good" bacteria that reside in the problem. Anxiety, depression and intestines and play a key role in other mental health issues are health. Research indicates that associated with IBS. A history of microflora in people with IBS sexual, physical or emotional abuse might differ from microflora in also might be a risk factor. healthy people. Diagnosis of Irritable bowel syndrome Prevention of Irritable Bowel Syndrome (IBS) (IBS) There's no test to definitively diagnose Finding ways to deal with stress may help IBS. Your doctor is likely to start with a prevent or ease symptoms of IBS. complete medical history, physical exam Consider trying: and tests to rule out other conditions [15].  Counseling. A counselor can help If you have IBS with diarrhea, you likely you learn to modify or change your will be tested for gluten intolerance responses to stress. Studies have (celiac disease). shown that psychotherapy can After other conditions have been ruled provide significant and long-lasting out, your doctor is likely to use one of reduction of symptoms. these sets of diagnostic criteria for IBS:  Biofeedback. Electrical sensors help  Rome criteria. These criteria include you receive information (feedback) abdominal pain and discomfort on your body's functions. The lasting on average at least one day a feedback helps you focus on making week in the last three months, subtle changes, such as relaxing associated with at least two of these certain muscles, to ease symptoms. factors: Pain and discomfort are  Progressive relaxation related to defecation, the frequency exercises. These exercises help you of defecation is altered, or stool relax muscles in your body, one by consistency is altered. one. Start by tightening the muscles

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www.idosr.org Bethany  Manning criteria. These criteria your symptoms, especially if you focus on pain relieved by passing have abdominal pain. Your doctor stool and on having incomplete might fill your large intestine with a bowel movements, mucus in the liquid (barium) to make any stool and changes in stool problems more visible on X-ray. This consistency. The more symptoms barium test is sometimes called a you have, the greater the likelihood lower GI series. of IBS. Laboratory tests can include:  Type of IBS. For the purpose of  Lactose intolerance tests. Lactase is treatment, IBS can be divided into an enzyme you need to digest the three types, based on your sugar found in dairy products. If you symptoms: constipation- don't produce lactase, you may have predominant, diarrhea-predominant problems similar to those caused by or mixed. IBS, including abdominal pain, gas Your doctor will also likely assess and diarrhea. Your doctor may order whether you have other signs or a breath test or ask you to remove symptoms that might suggest another, milk and milk products from your more serious, condition. These signs and diet for several weeks. symptoms include:  Breath test for bacterial  Onset of signs and symptoms after overgrowth. A breath test also can age 50 determine if you have bacterial  Weight loss overgrowth in your small intestine.  Rectal bleeding Bacterial overgrowth is more  Fever common among people who have  Nausea or recurrent vomiting had bowel surgery or who have  Abdominal pain, especially if it's not diabetes or some other disease that completely relieved by a bowel slows down digestion. movement, or occurs at night  Upper endoscopy. A long, flexible  Diarrhea that is persistent or tube is inserted down your throat awakens you from sleep and into the tube connecting your  Anemia related to low iron mouth and stomach (esophagus). A If you have these signs or symptoms, or if camera on the end of the tube allows an initial treatment for IBS doesn't work, the doctor to inspect your upper you'll likely need additional tests. digestive tract and obtain a tissue Additional tests sample (biopsy) from your small Your doctor may recommend several intestine and fluid to look for tests, including stool studies to check for overgrowth of bacteria. Your doctor infection or problems with your might recommend endoscopy if intestine's ability to take in the nutrients celiac disease is suspected [16]. from food (malabsorption). You may also  Stool tests. Your stool might be have a number of other tests to rule out examined for bacteria or parasites, other causes for your symptoms. or a digestive liquid produced in Imaging tests can include: your liver (bile acid), if you have  Flexible sigmoidoscopy. Your chronic diarrhea. doctor examines the lower part of Treatment of Irritable bowel syndrome the colon (sigmoid) with a flexible, Treatment of IBS focuses on relieving lighted tube (sigmoidoscope). symptoms so that you can live as  Colonoscopy. Your doctor uses a normally as possible. Mild signs and small, flexible tube to examine the symptoms can often be controlled by entire length of the colon. managing stress and by making changes  X-ray or CT scan. These tests in your diet and lifestyle. Try to: produce images of your abdomen  Avoid foods that trigger your and pelvis that might allow your symptoms doctor to rule out other causes of  Eat high-fiber foods

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www.idosr.org Bethany  Drink plenty of fluids (Welchol). Bile acid binders can  Exercise regularly cause bloating.  Get enough sleep  Your doctor might suggest that you medications. Medications such as eliminate from your diet: dicyclomine (Bentyl) can help relieve  High-gas foods. If you experience painful bowel spasms. They are bloating or gas, you might avoid sometimes prescribed for people items such as carbonated and who have bouts of diarrhea. These alcoholic beverages, caffeine, raw medications are generally safe but fruit, and certain vegetables, such as can cause constipation, dry mouth cabbage, broccoli and cauliflower. and blurred vision.  Gluten. Research shows that some  Tricyclic antidepressants. This type people with IBS report improvement of medication can help relieve in diarrhea symptoms if they stop depression as well as inhibit the eating gluten (wheat, barley and rye) activity of neurons that control the even if they don't have celiac intestines to help reduce pain. If you disease. have diarrhea and abdominal pain  FODMAPs. Some people are without depression, your doctor may sensitive to certain carbohydrates suggest a lower than normal dose of such as fructose, fructans, lactose (Tofranil), and others, known as FODMAPs — (Norpramine) or fermentable oligo-, di-, and (Pamelor). Side effects — which monosaccharides and polyols. might be reduced if you take the FODMAPs are found in certain medication at bedtime — can include grains, vegetables, fruits and dairy drowsiness, blurred vision, products. Your IBS symptoms might dizziness and dry mouth. ease if you follow a strict low-  SSRI antidepressants. Selective FODMAP diet and then reintroduce serotonin reuptake inhibitor (SSRI) foods one at a time. antidepressants, such as fluoxetine A dietitian can help you with these diet (Prozac, Sarafem) or paroxetine changes. (Paxil), may help if you're depressed If your problems are moderate or severe, and have pain and constipation. your doctor might suggest counseling —  Pain medications. Pregabalin especially if you have depression or if (Lyrica) or gabapentin (Neurontin) stress tends to worsen your symptoms. might ease severe pain or bloating. In addition, based on your symptoms Medications specifically for IBS your doctor might suggest medications Medications approved for certain people such as: with IBS include:  Fiber supplements. Taking a  (Lotronex). Alosetron is supplement such as psyllium designed to relax the colon and slow (Metamucil) with fluids may help the movement of waste through the control constipation. lower bowel. Alosetron can be  Laxatives. If fiber doesn't help prescribed only by doctors enrolled symptoms, your doctor may in a special program, is intended for prescribe magnesium hydroxide oral severe cases of diarrhea- (Phillips' Milk of Magnesia) or predominant IBS in women who polyethylene glycol (Miralax). haven't responded to other  Anti-diarrheal medications. Over- treatments, and isn't approved for the-counter medications, such as use by men [5]. It has been linked to loperamide (Imodium), can help rare but important side effects, so it control diarrhea. Your doctor might should only be considered when also prescribe a bile acid binder, other treatments aren't successful. such as cholestyramine (Prevalite),  (Viberzi). Eluxadoline colestipol (Colestid) or colesevelam can ease diarrhea by reducing

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www.idosr.org Bethany muscle contractions and fluid fluid secretion in your small secretion in the intestine, and intestine to help with the passage of increasing muscle tone in the stool. It's approved for women who rectum. Side effects can include have IBS with constipation, and is nausea, abdominal pain and mild generally prescribed only for women constipation. Eluxadoline has also with severe symptoms that haven't been associated with , responded to other treatments. which can be serious and more  Linaclotide (Linzess). Linaclotide common in certain individuals. also can increase fluid secretion in  (Xifaxan). This your small intestine to help you pass can decrease bacterial overgrowth stool. Linaclotide can cause diarrhea, and diarrhea. but taking the medication 30 to 60  Lubiprostone minutes before eating might help. (Amitiza). Lubiprostone can increase CONCLUSION IBS is a chronic functional disorder of the patients do not find complete gastrointestinal tract with symptoms of symptomatic relief, even when physicians abdominal pain and altered bowel habits explore off-label options [8] [9]. that include diarrhea, constipation, or Well-designed studies are needed to both. Patients who suffer from IBS often support the use and optimize the dosing have an impaired quality of life. IBS for older medications that are used off- affects 10% to 20% of the general label. Additionally, comparative population, but these percentages are effectiveness studies, which would help likely underestimated, since only a small guide treatment selection, are lacking for portion of patients with IBS symptoms IBS medications. Emerging treatment seek medical attention. Patients who options for IBS, such as , suffer from IBS often do not respond to eluxadoline, and rifaximin, show promise, lifestyle and diet modifications. Although but better understanding of the disease a few medications are available to treat pathophysiology is needed to facilitate IBS symptoms, several of these drug development. have strict limitations on use. Many REFERENCES 1. Alexandros Hadjivasilis, Journal of Gastroenterology. 20 Constantinos Tsioutis, Adamantios (14): 3976–85. Michalinos, Dimitrios Ntourakis, 4. Chang L (2011). "The role of stress Dimitrios K. Christodoulou, and on physiologic responses and Aris P. Agouridis (2019). "New clinical symptoms in irritable insights into irritable bowel bowel syndrome". syndrome: from pathophysiology Gastroenterology. 140 (3): 761–5. to treatment". Ann Gastroenterol. 5. Fukudo S, Nomura T, Muranaka M, 32 (6): 554–564. Taguchi F (1993). "Brain-gut 2. Barreau F, Ferrier L, Fioramonti J, response to stress and cholinergic Bueno L (2007). "New insights in stimulation in irritable bowel the etiology and pathophysiology syndrome. A preliminary study". of irritable bowel syndrome: Journal of Clinical contribution of neonatal stress Gastroenterology. 17 (2): 133–41. models". Pediatric Research. 62 (3): 6. Hulisz D (2004). "The burden of 240–5. illness of irritable bowel 3. Beatty JK, Bhargava A, Buret AG syndrome: current challenges and (2014). "Post-infectious irritable hope for the future". Journal of bowel syndrome: mechanistic Managed Care Pharmacy. 10 (4): insights into chronic disturbances 299–309. following enteric infection". World 7. Li J, Zhu W, Liu W, Wu Y, Wu B (2016). "Rifaximin for Irritable

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