Irritable bowel syndrome (IBS) is a group of symptoms including abdominal pain and changes in the pattern of bowel movements without any evidence of underlying damage. These symptoms occur over a long time, often years. It has been classified into four main types depending on whether diarrhea is common, constipation is common, both are common, or neither occurs very often (IBS-D, IBS-C, IBS-M, or IBS-U respectively). IBS negatively affects quality of life and may result in missed school or work. Disorders such as anxiety, major depression, and chronic fatigue syndrome are common among people with IBS.
Irritable bowel syndrome (IBS) is an often misunderstood and underdiagnosed condition that affects about 15.3 million people in the United States.
No one remedy works for all patients, so there’s a great medical need to develop new therapies for IBS, says Tara Altepeter, M.D., a gastroenterologist with the U.S. Food and Drug Administration (FDA). That’s why the FDA is working to bring more treatments to the market.
“There’s a lot of new research about the role of carbohydrates, and specifically a nutrient called polyols, in triggering irritable bowel syndrome in some patients,” Altepeter says. “In addition, researchers are more closely examining the role of dietary modification as a treatment for patients with IBS.”
IBS is a gastrointestinal disorder that affects the large intestine (colon) but doesn’t cause inflammation or permanent damage. Common symptoms of IBS include abdominal pain, bloating, cramping, excessive gas, mucous in the stool, and alterations in bowel habits (constipation and/or diarrhea).
The symptoms may come and go, and can change in the same patient. Sometimes the pain from IBS can be so severe that it’s disabling and patients can’t do routine things. Doctors don’t know what causes IBS, and there is no known cure.
Studies estimate that as many as 20% of Americans suffer from IBS. Many people may not know they have this gastrointestinal disorder. They might have occasional diarrhea and constipation and think it’s caused by something they ate or a virus, so they don’t see a doctor to get a proper diagnosis. When they do, doctors must first rule out that the symptoms aren’t caused by a disease or another condition.
“There are many conditions that have a female or male predominance, but we don’t understand why women have a higher prevalence of IBS,” Altepeter says.
IBS is most common among people younger than 45, and patients usually first experience symptoms when they’re in their late 20s. People who have a family history of IBS are also more likely to develop the condition.
Depression, anxiety and other psychological problems are common in people with IBS.
There are 3 main types of irritable bowel syndrome
1. IBS with constipation (IBS-C) – the patient experiences stomach pain, discomfort, bloating, infrequent or delayed bowel movements, or hard or lumpy stools.
2. IIBS with diarrhea (IBS-D) – the patient experiences stomach pain, discomfort, an urgent need to go to the toilet, very frequent bowel movements, or watery or loose stools.
IBS-D stands for irritable bowel syndrome with diarrhea. The most common symptoms of IBS-D include:
- Frequent stools
- Feeling as if you are unable to completely empty your bowels during bowel movements
People with IBS-D also may experience signs and symptoms of
- Abdominal pain or discomfort
- Sudden urges to have a bowel movement
- Loose stools
IBS-C stands for irritable bowel syndrome with constipation. The most common symptoms of IBS-C include
- Infrequent stools
- Straining during bowel movements
- Feeling as if you are unable to completely empty your bowels during bowel movements
- Feeling as if you need to have a bowel movement but are unable
- Abdominal pain
3. IIBS with alternating stool pattern (IBS-A) – the patient experiences both constipation and diarrhea.
These assessments can be used to identify the IBS subtype :[Rx]
IBS with predominant constipation (IBS-C) – Patient reports that abnormal bowel movements are usually constipation (BSFS type 1 or 2).
IBS with predominant diarrhoea (IBS-D) – Patient reports that abnormal bowel movements are usually diarrhoea (BSFS type 6 or 7).
IBS with mixed bowel habits (IBS-M) – Patient reports that abnormal bowel movements are usually both constipation and diarrhoea (more than one-quarter constipation and more than one-quarter diarrhoea).
Causes of Irritable Bowel Syndrome
The exact cause of IBS is unknown, but experts think that several factors may be involved. These include:
- Problems with digestion – the muscles of the intestines work to squeeze food through the digestive system. In people with IBS, this process may not be working properly, so that food moves through the digestive system too slowly or too quickly. If it moves too slowly it can lead to constipation; if it moves too quickly it may cause diarrhea.
- Overactivity of the nerves in the intestines – if the nerves in the digestive system are oversensitive, they may cause people to feel more pain. This oversensitivity may cause the crampy abdominal pain associated with IBS.
- Gastrointestinal infections – some people develop IBS after a gastrointestinal infection.
- Genetic and early life factors – close relatives of a person with IBS may be more likely to develop IBS themselves; some early childhood experiences (e.g. poor nutrition) may also be involved in the development of IBS.
IBS is not caused by blood or biochemical disorder.
Symptoms of irritable bowel syndrome
Manifestations of IBS are as follows
Altered bowel habits
Altered bowel habits in IBS may have the following characteristics
Constipation variably results in complaints of hard stools of narrow caliber, painful or infrequent defecation, and intractability to laxatives
Diarrhea usually is described as small volumes of loose stool, with evacuation preceded by urgency or frequent defecation
Postprandial urgency is common, as is an alternation between constipation and diarrhea
Characteristically, one feature generally predominates in a single patient, but significant variability exists among patients
Abdominal pain in IBS is protein but may have the following characteristics
Pain frequently is diffuse without radiation
Common sites of pain include the lower abdomen, specifically the left lower quadrant
Acute episodes of sharp pain are often superimposed on a more constant dull ache
Meals may precipitate pain
Defecation commonly improves pain but may not fully relieve it
Pain from presumed gas pockets in the splenic flexure may masquerade as anterior chest pain or left upper quadrant abdominal pain
Additional symptoms consistent with irritable bowel syndrome are as follows:
Clear or white mucorrhea of a noninflammatory etiology
Sexual dysfunction (including dyspareunia and poor libido)
Urinary frequency and urgency have been noted
Worsening of symptoms in the perimenstrual period
Symptoms not consistent with irritable bowel syndrome should alert the clinician to the possibility of organic pathology. Inconsistent symptoms include the following
Onset in middle age or older
Acute symptoms (irritable bowel syndrome is defined by chronicity)
Anorexia or weight loss
Other symptoms which sometimes occur – include
- Feeling sick (nausea).
- Poor appetite.
- A backache.
- Muscle pains.
- Feeling quickly full after eating.
- Bladder symptoms (an associated irritable bladder).
Many people fall somewhere in between, with flare-ups of symptoms from time to time. Some doctors group people with IBS into one of three categories:
- Those with abdominal pain or discomfort, and the other symptoms are mainly bloating and constipation.
- Those with abdominal pain or discomfort, and the other symptoms are mainly urgency to get to the toilet and diarrhea.
- Those who alternate between constipation and diarrhea.
Diagnosis of irritable bowel syndrome
If there are specific signs or symptoms that may suggest another condition, further testing may be required. The signs or symptoms may include:
- localized swelling in the rectum and abdomen
- weight loss (unexplained)
- abdominal pain at night
- progressively worsening symptoms
- significant blood in the stool
- a family history of inflammatory bowel disease, colorectal cancer, or celiac disease
- Full blood count (FBC) – to rule out lack of iron in the blood (anemia), which is associated with various gut disorders.
- Erythrocyte sedimentation rate (ESR) or C-reactive protein (CRP) – which can show if there is inflammation in the body (which does not occur with IBS).
- A blood test for coeliac disease.
- In women, a blood test to rule out the cancer of the ovary, called CA 125.
- A stool test to look for a protein called fecal calprotectin. This may be present if you have Crohn’s disease or ulcerative colitis, but is not present in IBS
|Diagnostic criteria||Symptoms, signs, and laboratory investigations included in criteria|
|Manning (1978)||IBS is defined as the symptoms given below with no duration of symptoms described. The number of symptoms that need to be present to diagnose IBS is not reported in the paper, but a threshold of three positive is the most commonly used:|
|Abdominal pain relieved by defecation|
|More frequent stools with the onset of pain|
|Looser stools with the onset of pain|
|Mucus per rectum|
|The feeling of incomplete emptying|
|Patient-reported visible abdominal distension|
|Kruis (1984)||IBS is defined by a logistic regression model that describes the probability of IBS. Symptoms need to be present for more than two years.|
|Abdominal pain, flatulence, or bowel irregularity|
|Description of character and severity of abdominal pain|
|Alternating constipation and diarrhea|
|Signs that exclude IBS (each determined by the physician):|
|Abnormal physical findings and/or history pathognomonic for any diagnosis other than IBS|
|Erythrocyte sedimentation rate > 20 mm/2 h|
|Leukocytosis > 10000/cc|
|Anemia (Hemoglobin < 12 for women or < 14 for men)|
|Impression by the physician that the patient has rectal bleeding|
|Rome I (1990)||Abdominal pain or discomfort relieved with defecation, or associated with a change in stool frequency or consistency,|
|PLUS two or more of the following on at least 25% of occasions or days for 3 mo:|
|Altered stool frequency|
|Altered stool form|
|Altered stool passage|
|Passage of mucus|
|Bloating or distension|
|Rome II (1999)||Abdominal discomfort or pain that has two of three features for 12 wk (need not to be consecutive) in the last one year:|
|Relieved with defecation|
|Onset associated with a change in frequency of stool|
|Onset associated with a change in form of stool|
|Rome III (2006)||Recurrent abdominal pain or discomfort three days per month in the last 3 mo associated with two or more of:|
|Improvement with defecation|
|Onset associated with a change in frequency of stool|
|Onset associated with a change in form of stool|
IBS: Irritable bowel syndrome; 5-HT: 5-hydroxytryptamine.
Pattern of study
- The study was an open-label, single group, and non-controlled clinical trial.
Washout/preparatory period (if required): 4 weeks
Treatment period: 12 weeks
- This clinical trial has been registered under CTRI (Ref-CTRI/2012/01/002348).
- Ethical clearance
- The study was approved by the Institutional Ethics Committee (Ref PGT/7-A/Ethics/210-11/1858).
Patients of either sex with age between 18 and 65 years
Known case of IBS as per Rome III criteria[Rx](Symptoms of recurrent abdominal pain or discomfort and a marked change in bowel habit for at least 6 months, with symptoms experienced on at least 3 days/month in the last 3 months associated with two or more of the following:
Pain is relieved by defecation
Onset associated with a change of frequency of stools
Onset associated with a change in form (appearance) of stools.
Willing and able to participate in the study.
Patients with bleeding per rectum.
Mixed infection with parasites such as round worms, hook worms etc.
Patients with evidence of malignancy.
Patients with diabetes mellitus (B.S. [F] >126 mg% and/or B.S. [2 h. PP] >200 mg% or hemoglobin A1c (HbA1c > 6.5%).
Patient with poorly controlled hypertension (>160/100 mm Hg).
Patients on prolonged (>6 weeks) medication with corticosteroids, anti-depressants, anti-cholinergics, etc., or any other drugs that may have an influence on the outcome of the study.
Patients suffering from major systemic illness necessitating long term drug treatment Rheumatoid arthritis, tuberculosis, psycho-neuro-endocrinal disorders, etc.
Patients who have a past history of atrial fibrillation, acute coronary syndrome, myocardial infarction, stroke or severe arrhythmia in the last 6 months.
A symptomatic patient with clinical evidence of heart failure.
Patients with concurrent serious hepatic disorder (defined as aspartate amino transferase (AST) and/or alanine amino transferase (ALT), total bilirubin, alkaline phosphatase (ALP) >2 times upper normal limit) or renal disorders (defined as serum creatinine >1.2 mg/dL), severe pulmonary dysfunction (uncontrolled bronchial asthma and/or chronic obstructive pulmonary disease), or any other condition that may jeopardize the study.
Alcoholics and/or drug abusers.
History of hypersensitivity to the trial drug or any of its ingredients.
Patients who have completed participation in any other clinical trial during the past 6 months.
Any other condition which the principal investigator thinks may jeopardize the study.
- Routine investigations were done, before (to rule out any other pathology) and after treatment (to assess any untoward effect of trial drug during the regimen).
- Hemoglobin, total leucocyte count, differential leucocyte count (neutrophil, eosinophil, basophil, lymphocytes, monocytes), erythrocyte sedimentation rate.
- Blood sugar (fasting, PP), HbA1c, blood urea, serum uric acid, mg/dl, serum creatinine, serum glutamic oxaloacetic transaminase (AST), serum glutamic-pyruvic transaminase. (ALT), total protein, serum albumin, serum globulin, A/G ratio, serum bilirubin, conjugated bilirubin, unconjugated bilirubin, serum ALP.
Stool examination (Microscopic)
- Parasites (ova/cyst), mucous, vegetative cells, occult blood.
- This disease is a functional disorder, rest of the biochemical and stool examination were conducted to rule out the exclusion criteria and after treatment the safety profile of the drug.
- Bilvadileha has been administered to the patients at the dose of 10 g twice a day orally after food with luke warm water for the duration of 12 weeks.
Methods of assessment
- The assessment of IBS was done at the interval of 14 days on the basis of relief in chief complaints of IBS, disease specific Ayurvedic parameters and IBS severity score.
Response at 12 weeks
The positive response to treatment-decrease in IBS severity score by >50%.
Partial response to treatment-decrease in IBS severity score by 30-50%.
No response to treatment-decrease in IBS severity score by <30%.
Treatments of Irritable Bowel Syndrome
Treatments for IBS vary from patient to patient and include changes in diet, nutrition, and exercise. Some patients require medications to manage their symptoms. Currently, there are no medications that cure IBS.
Pharmacologic agents used for the management of symptoms in IBS include the following:
Anticholinergics (eg, dicyclomine, hyoscyamine)
Antidiarrheals (eg, diphenoxylate, loperamide)
Tricyclic antidepressants (eg, imipramine, amitriptyline)
Serotonin receptor antagonists (eg, alosetron)
Chloride channel activators (eg, lubiprostone)
Guanylate cyclase C (GC-C) agonists (eg, linaclotide)
Antispasmodics (eg, peppermint oil, pinaverium, trimebutine, cimetropium/dicyclomine)
Potentially, rifaxamin (this is still investigational and not FDA approved)
“IBS is not like other chronic conditions, such as hypertension, which is constant. IBS is a variable condition. Even without treatment, the problem might go away in some patients. But the symptoms might return after a few months,” Altepeter says.
What medications treat diarrhea (IBS-D) and constipation (IBS-D) in irritable bowel syndrome?
- Antidiarrheal medications – such as loperamide (Imodium), attapulgite (Kaopectate), and diphenoxylate and atropine (Lomotil) can be helpful if loose stools are one of the main signs. Eluxadoline (Viberzi) is a prescription for the treatment of irritable bowel syndrome with diarrhea (IBS-D).
- For females with IBS who experience severe diarrhea, alosetron has been used.
- Rifaximin – is an antibiotic for the treatment of irritable bowel syndrome with diarrhea (IBS-D) and IBS-related bloating.
- Bile acid binders – including cholestyramine colestipol or colesevelam can help some patients with IBS-D, but can also cause bloating.
Medicine for constipation medication
- Over-the-counter laxatives such as polyethylene glycol 3350 ( (MiraLax), bisacodyl (Dulcolax), and psyllium seed husks (Metamucil) can help relieve constipation and keep bowel movements regular. Senna laxatives (Senokot, Ex-Lax Gentle Nature) may be taken short-term. Prescription laxatives such as lactulose (Constulose) may also be prescribed.
- Two drugs specifically used to treat IBS are lubiprostone, a laxative, and linaclotide, a constipation medication.
- SSRI antidepressants fluoxetine, citalopram, sertraline, paroxetine, and escitalopram may be helpful for those with constipation (IBS-C), but they can trigger IBS attacks in patients with diarrhea (IBS-D)
Medications treat pain and cramping in irritable bowel syndrome (IBS)
- Antispasmodics, such as metoclopramide (Reglan), dicyclomine (Bentyl), and hyoscyamine(Levsin), decrease symptoms of pain and cramping.
- Antidepressants such as amitriptyline (Elavil, Paregoric), doxepin ( (Silenor), desipramine(Norpramin), nortriptyline (Pamelor), and imipramine (Tofranil) may help with abdominal pain but due to side effects are usually reserved for severe cases.
Symptoms of irritable bowel syndrome
- Antidepressants in low doses, such as tricyclic antidepressants (TCAs) and selective serotonin reuptake inhibitors (SSRIs), may help relieve symptoms associated with IBS.
- Bismuth subsalicylate (Pepto-Bismol) and magnesium hydroxide (Milk of Magnesia).
- Antibiotics may be used when small intestinal bacterial overgrowth (SIBO) is suspected.
- Antianxiety medications such as diazepam (Valium), lorazepam (Ativan), and clonazepam (Klonopin) are occasionally prescribed short-term for people whose anxiety worsens their irritable bowel syndrome symptoms.
No one medication works for all people suffering from IBS.
IBS and Diet
Diagnosis of Irritable Bowel Syndrome
- No specific laboratory or imaging test can be performed to diagnose irritable bowel syndrome. Diagnosis involves excluding conditions that produce IBS-like symptoms and then following a procedure to categorize the patient’s symptoms.
- Ruling out parasitic infections, lactose intolerance, small intestinal bacterial overgrowth, and celiac disease is recommended for all patients before a diagnosis of irritable bowel syndrome is made. In patients over 50 years old, they are recommended to undergo a screening colonoscopy.
- IBS sufferers are at increased risk of being given inappropriate surgeries such as appendectomy, cholecystectomy, and a hysterectomy due to their IBS symptoms being misdiagnosed as other medical conditions.
Differential diagnosis of Irritable Bowel Syndrome
- Colon cancer, inflammatory bowel disease, thyroid disorders, and giardiasis can all feature abnormal defecation and abdominal pain. Less common causes of this symptom profile are carcinoid syndrome, microscopic colitis, bacterial overgrowth, and eosinophilic gastroenteritis; IBS is, however, a common presentation, and testing for these conditions would yield low numbers of positive results, so it is considered difficult to justify the expense.
- Some people, managed for years for IBS, may have non-celiac gluten sensitivity (NCGS). Gastrointestinal symptoms of IBS are clinically indistinguishable from those of NCGS, but the presence of any of the following non-intestinal manifestations suggest a possible NCGS: headache or migraine, “foggy mind”, chronic fatigue, fibromyalgia, joint and muscle pain, leg or arm numbness,tingling of the extremities, dermatitis (eczema or skin rash),atopic disorders allergy to one or more inhalants, foods or metals (such as mites, graminaceae, parietaria, cat or dog hair, shellfish, or nickel), depression, anxiety, anemia,iron-deficiency anemia, folate deficiency, asthma, rhinitis, eating disorders,neuropsychiatric disorders (such as schizophrenia, autism, peripheral neuropathy, ataxia, attention deficit hyperactivity disorder) or autoimmune diseases. Improvement with a gluten-free diet of immune-mediated symptoms, including autoimmune diseases, once having reasonably ruled out coeliac disease and wheat allergy, is another way to realize a differential diagnosis.
- Because many causes of diarrhea give IBS-like symptoms, the American Gastroenterological Association published a set of guidelines for tests to be performed to rule out other causes of these symptoms. These include gastrointestinal infections, lactose intolerance, and coeliac disease.
- Research has suggested these guidelines are not always followed. Once other causes have been excluded, the diagnosis of IBS is performed using a diagnostic algorithm. Algorithms include the Manning criteria, the obsolete Rome I and II criteria, and the Kruis criteria, and studies have compared their reliability. The more recent Rome III process was published in 2006 and the Rome IV criteria were published in 2016.
The Rome IV criteria include recurrent abdominal pain, on average, at least 1 day/week in the last 3 months, associated with two or more of the following criteria
- Related to defecation
- Associated with a change in frequency of stool
- Associated with a change in form (appearance) of stool.
- Physicians may choose to use one of these guidelines or may simply choose to rely on their own anecdotal experience with past patients.
- The algorithm may include additional tests to guard against misdiagnosis of other diseases as IBS. Such “red flag” symptoms may include weight loss, gastrointestinal bleeding, anemia, or nocturnal symptoms. However, red flag conditions may not always contribute to accuracy in diagnosis; for instance, as many as 31% of IBS patients have blood in their stool, many possibly from hemorrhoidal bleeding.
- The diagnostic algorithm identifies a name that can be applied to the patient’s condition based on the combination of the patient’s symptoms of diarrhea, abdominal pain, and constipation. For example, the statement “50% of returning travelers had developed functional diarrhea while 25% had developed IBS” would mean half the travelers had diarrhea while a quarter had diarrhea with abdominal pain.
- While some researchers believe this categorization system will help physicians understand IBS, others have questioned the value of the system and suggested all IBS patients have the same underlying disease but with different symptoms.
Investigations of Irritable Bowel Syndrome
Investigations are performed to exclude other conditions:
- Stool microscopy and culture (to exclude infectious conditions)
- Blood tests: Full blood examination, liver function tests, erythrocyte sedimentation rate, and serological testing for coeliac disease
- Abdominal ultrasound (to exclude gallstones and other biliary tract diseases)
- Endoscopy and biopsies (to exclude peptic ulcer disease, coeliac disease, inflammatory bowel disease, and malignancies)
- Hydrogen breath testing (to exclude fructose and lactose malabsorption)
Misdiagnosis of Irritable Bowel Syndrome
- Some common examples of misdiagnosis include infectious diseases, coeliac disease, Helicobacter pylori, parasites (non-protozoal).
- Coeliac disease, in particular, is often misdiagnosed as IBS. The American College of Gastroenterology recommends all patients with symptoms of IBS be tested for coeliac disease.
Bile acid malabsorption is also sometimes missed in patients with diarrhea-predominant IBS. SeHCAT tests suggest around 30% of D-IBS patients have this condition, and most respond to bile acid sequestrants.
Chronic use of certain sedative-hypnotic drugs, especially the benzodiazepines, may cause irritable bowel-like symptoms that can lead to a misdiagnosis of irritable bowel syndrome.
Several medical conditions, or comorbidities, appear with greater frequency in patients diagnosed with IBS.
- Neurological/psychiatric – A study of 97,593 individuals with IBS identified comorbidities such as a headache, fibromyalgia, and depression. IBS occurs in 51% of chronic fatigue syndrome patients and 49% of fibromyalgia patients, and psychiatric disorders occur in 94% of IBS patients.
- Inflammatory bowel disease – IBS may be a type of low-grade inflammatory bowel disease. Researchers have suggested IBS and IBD are interrelated diseases, noting that patients with IBD experience IBS-like symptoms when their IBD is in remission. A three-year study found that patients diagnosed with IBS were 16.3 times more likely to be diagnosed with IBD during the study period. Serum markers associated with inflammation have also been found in patients with IBS.
- Abdominal surgery – IBS patients were at increased risk of having unnecessary gall bladder removal surgery not due to an increased risk of gallstones, but rather to abdominal pain, awareness of having gallstones, and inappropriate surgical indications. These patients also are 87% more likely to undergo abdominal and pelvic surgery and three times more likely to undergo gallbladder surgery. Also, IBS patients were twice as likely to undergo a hysterectomy.
- Endometriosis – One study reported a statistically significant link between migraine headaches, IBS, and endometriosis.
- Other chronic disorders – Interstitial cystitis may be associated with other chronic pain syndromes, such as irritable bowel syndrome and fibromyalgia. The connection between these syndromes is unknown.
“Drugs are a last option. Patients should try dietary modifications, relaxation techniques, and other lifestyle changes, such as exercise, before resorting to medication,” Altepeter says.
Certain foods and drinks can trigger IBS symptoms in some patients. The most common are foods rich in carbohydrates, spicy or fatty foods, milk products, coffee, alcohol, and caffeine.
IBS and Children
It’s difficult to diagnose IBS in children because its symptoms are so common, and may be seen in a variety of conditions. Young children may not verbalize their symptoms in the same way that teenagers or adults can. The National Digestive Diseases Information Clearinghouse (NDDIC) reports that one study of children in North America found that girls and boys are equally prone to having IBS. The study also found that as many as 14% of high school students and 6% of middle school students have IBS.
Diagnosing IBS in young children remains a challenge, as does its treatment. FDA has not approved any drugs for treating IBS symptoms in children.
General dietary advice for IBS
Current national guidelines about IBS include the following points about diet, which may help to minimize symptoms:
- Have regular meals and take time to eat at a leisurely pace.
- Avoid missing meals or leaving long gaps between eating.
- Drink at least eight cups of fluid per day, especially water or other non-caffeinated drinks. This helps to keep the stools (feces) soft and easy to pass along the gut.
- Restrict tea and coffee to three cups per day (as caffeine may be a factor in some people).
- Restrict the number of fizzy drinks that you have to a minimum.
- Don’t drink too much alcohol. (Some people report an improvement in symptoms when they cut down from drinking a lot of alcohol.)
- Consider limiting intake of high-fiber food (but see the section above where an increase may help in some cases).
- Limit fresh fruit to three portions (of 80 g each) per day.
- If you have diarrhea, avoid sorbitol, an artificial sweetener found in sugar-free sweets (including chewing gum) and in drinks, and in some diabetic and slimming products.
- If you have a lot of wind and bloating, consider increasing your intake of oats (for example, oat-based breakfast cereal or porridge) and linseeds (up to one tablespoon per day). You can buy linseeds from health food shops.
The advice about fiber in treating IBS has changed somewhat over the years. Fiber (roughage – and other bulking agents) is the part of the food which is not absorbed into the body. It remains in your gut and is a main part of stools. There is a lot of fiber in fruit, vegetables, cereals, wholemeal bread, etc. Some research studies have shown that a high-fiber diet helps symptoms in IBS; others have shown the opposite. In some people, perhaps particularly those with constipation, a high-fiber diet definitely helps. In others, often those with diarrhea, a high-fiber diet makes symptoms worse. If you keep a symptom diary, you can work out which is true for you. Then you can adjust your fiber intake accordingly.
- Dietary sources of soluble fiber include oats, ispaghula (psyllium), nuts and seeds, some fruit and vegetables and pectins. A fiber supplement called ispaghula powder is also available from pharmacies and health food shops. This seems to be the most beneficial type of supplement.
- Insoluble fiber is chiefly found in corn (maize) bran, wheat bran, and some fruit and vegetables. In particular, avoid bran as a fiber supplement.
|Which patients may benefit?||Time to achieve efficacy on key symptoms||Common adverse effects and management|
|Advanced dietary strategies|
|Low-FODMAP diet||• After conservative dietary management strategies have failed
||• Reduction in severity of overall GI symptoms within seven days[Rx] • May take up to eight weeks for symptom response to appear if dietary-mediated changes to gut microbiota are the cause of the improvement[Rx]||• Further research needed to determine if there are potential adverse effects on the gut microbiota associated with long-term use[Rx] • Potential for inadequate nutrient intake with stringent dietary restriction[Rx]|
|Therapies targeting constipation|
|Linaclotidea,[Rx]||• Constipation, pain or bloating as the predominant symptom||• Improvement in bowel frequency seen as early as week 1 • Maximal effect on abdominal pain and bloating may take longer (8–10 weeks)||• Diarrhoea – usually resolves within seven days or with temporary cessation of treatment|
|Lubiprostone[Rx]||• Constipation as the predominant symptom||• Improvements in bowel movement frequency, straining, constipation severity and stool consistency seen at month 1 • Improvements in abdominal pain and bloating seen at month 2||• Diarrhoea and nausea • To limit dose-dependent nausea, should be taken with meals|
|Therapies targeting diarrhoea|
|Loperamideb||• Diarrhoea as the dominant symptom (for acute episodes)||• Can be used on an as-needed basis, but patients may take a fixed dose to avoid diarrhoea episodes||• Constipation (treatment should be stopped in severe cases)|
|Eluxadolinec,[Rx]||• Diarrhoea, abdominal pain or bloating as the predominant symptom||• Significant improvement in abdominal pain and stool symptoms from week 1 onwards • Maximum effect on pain may take four to six weeks||• Constipation – can be minimised by avoiding concomitant use with other medicines that may cause constipation|
|Cholestyramine||• IBS-D with increased colonic bile acid • After other pharmacological therapies targeting diarrhoea have been tried||• Within one to three weeks • Stop after one to three months if the therapeutic effect is not adequate||• Should be started at a low dose and gradually increased to reduce the incidence and intensity of adverse effects such as nausea and upper GI symptoms[Rx] • Can reduce the bioavailability of other drugs so should be taken at a different time of day|
|Ondansetron[Rx]||• Mild to moderate symptoms of diarrhoea (not severe cases)||• Onset of effect within one week in most cases • Improves loose stools, frequency, and urgency||• Constipation (can be managed with dose reduction)|
|Rifaximin[Rx],[Rx]||• Bloating as the predominant symptom||• Significant relief of IBS symptoms, bloating, abdominal pain, and loose or watery stools after two weeks||• Antibiotic resistance of GI flora a concern if use widespread[Rx] • Long-term efficacy uncertain – effect gradually disappears and re-treatment is necessary in a large proportion of patients to retain symptom improvement[Rx]|
|Therapies targeting pain|
|Antispasmodics||• Pain as the predominant symptom (to provide symptomatic short-term relief)||• Effect on pain is usually immediate (within an hour)||• Use may be limited by anticholinergic adverse events[Rx]|
|TCAs||• Patients with IBS-D • Patients with insomnia, anorexia, or weight loss||• Patients usually started at low doses to minimise the potential for side effects • If an effect is not seen within a month, the dose may be increased||• Constipation • Drowsiness, dry mouth • Side effects frequently develop as the dose is increased|
|SSRIs||• Patients with IBS-C • Patients with anxiety or depression||• Onset of therapeutic benefit seems to occur within the first three to four weeks (but may take up to eight weeks)||• Diarrhoea • Sleep disturbances • Nervousness|
All other treatments included in the table are not currently approved by the EMA for the management of IBS.
EMA: European Medicines Agency; FODMAP: fermentable oligosaccharides, disaccharides, monosaccharides and polyols; GI: gastrointestinal; IBS-C: irritable bowel syndrome with constipation predominance; IBS-D: irritable bowel syndrome with diarrhoea predominance; SSRIs: selective serotonin re-uptake inhibitors; TCAs: tricyclic antidepressants.
The low-FODMAP diet
Recently, it has been discovered that a low-FODMAP diet may help some people with IBS.
FODMAP stands for Fermentable Oligosaccharides, Disaccharides, Monosaccharides, and Polyols. These are a group of carbohydrates found within foods, which may make IBS symptoms worse. Examples of foods to avoid in a low-FODMAP diet include:
- Certain fruits, such as apples, cherries, peaches, and nectarines.
- Some green vegetables, such as peas, cabbage, broccoli, and Brussels sprouts.
- Artificial sweeteners.
- Foods high in lactose, such as milk, ice cream, cream cheeses, chocolate, and sour cream.
If you wish to try a low-FODMAP diet, you should discuss this with a dietician. It is difficult to cut down on so many foods and keep eating a healthy diet without specialist advice. Your GP can arrange a referral to a dietician, and they can help you eat the right things.
Individual food intolerance
- Some people with IBS find that one or more individual foods can trigger symptoms, or make symptoms worse (food intolerance or sensitivity). If you are not sure if a food is causing symptoms, it may be worth discussing this with a doctor who may refer you to a dietician.
- A dietician may be able to advise on an exclusion diet. For example, one meat, one fruit, and one vegetable. Then, advise on adding in different foods gradually to your diet to see if any cause the symptoms. It may be possible to identify one or more foods that cause symptoms.
- This can be a tedious process, and often no problem food is found. However, some people say that they have identified one or more foods that cause symptoms, and then can control symptoms by not eating them.
The foods that are most commonly reported to cause IBS symptoms in the UK are:
- Wheat (in bread and cereals).
- Dairy products.
- Coffee (and other caffeine-rich drinks such as tea and cola).
- Probiotics are nutritional supplements that contain good germs (bacteria). That is bacteria that normally live in the gut and seem to be beneficial. Taking probiotics may increase the good bacteria in the gut which may help to ward off bad bacteria that may have some effect on causing IBS symptoms.
- You can buy probiotic capsules (various brands) from pharmacies. The dose is on the product label. You can also buy foods that contain probiotic bacteria. These include certain milk drinks, yogurts, cheeses, frozen yogurts, and ice creams. They may be labeled as ‘probiotic’, ‘containing bacterial cultures’ or ‘containing live bacteria’.
Antispasmodic medicines for tummy (abdominal) pain
- These are medicines that relax the muscles in the wall of the gut. Your doctor may advise one if you have spasm-type pains. There are several types of antispasmodics. For example, mebeverine, hyoscine and peppermint oil. They work in slightly different ways.
- Therefore, if one does not work well, it is worth trying a different one. If one is found to help then you can take it as required when pain symptoms flare up. Many people take an antispasmodic medicine for a week or so at a time to control pain when bouts of pain flare up. Some people take a dose before meals if pains tend to develop after eating.
Constipation is sometimes a main symptom of irritable bowel syndrome (IBS). If so, it may help if you increase your fibre as discussed earlier (that is, with soluble fiber such as ispaghula). Sometimes laxatives are advised for short periods if the increasing fiber is not enough to ease a troublesome bout of constipation. It is best to avoid lactulose if you suffer from IBS.
A new medicine called linaclotide has been approved for people who have constipation as a main symptom of IBS. It works in a completely different way to other medicines for treating constipation. It is taken once a day and has been shown to reduce pain, bloating and constipation symptoms.
- An antidiarrhoeal medicine may be useful if diarrhea is the main symptom. Loperamide is the most commonly used antidiarrhoeal medicine for IBS. You can buy this at pharmacies as an over-the-counter medicine. You can also get it on prescription which may be more cost-effective if you need to take it regularly.
- Peppermint oil may help with bloating and wind. It is available over-the-counter or on prescription. For some people, peppermint oil also helps with tummy pains and spasms.
- Lubiprostone – is a locally acting chloride channel activator that enhances chloride chloride-rich intestinal fluid secretion[Rx]. In a first step it was approved by the Food and Administration (FDA) for use in chronic idiopathic constipation and for women with IBS-C. However, its use is currently only suitable for women with IBS and severe constipation that has been refractory to other forms of treatment. Serious adverse events were similar to placebo. However, the long-term security remains to be established. been refractory to other treatments[Rx].
- Tegaserod – a first of the agonists of the 5-hydroxytryptamine (5-HT4) receptor class of drugs that stimulate the release of neurotransmitters and increase colonic motility, was approved for IBS and constipation but removed from the market in 2007 because of cardiovascular side effects[Rx]. It’s a 5-HT4 receptor agonist that in clinical trials has been reported to reduce the general symptoms of IBS patients in comparison to attested placebo[Rx]. The Linaclotide, a guanylate cyclase agonist stimulates intestinal fluid secretion and transit, has been approved by the United States FDA for treatment of IBS with constipation in 2012.
- A tricyclic antidepressant is sometimes used to treat IBS. In particular, it tends to work best if pain and diarrhoea are the main symptoms. An example is amitriptyline. (Tricyclic antidepressants have other actions separate to their action on depression.
- They are used in a variety of painful conditions, including IBS.) Other types of antidepressants, called selective serotonin reuptake inhibitors (SSRIs) are also occasionally used for IBS. For example, a tablet called fluoxetine. They may work by affecting the way you feel pain.
- Unlike antispasmodics, you need to take an antidepressant regularly rather than as required. Therefore, an antidepressant is usually only advised if you have persistent symptoms, or frequent bad flare-ups that have not been helped by other treatments.
Possible new treatments
Various other treatments show promise. For example:
- Rifaximin is an antibiotic but mainly stays in the gut and very little is absorbed into the body. The theory is that it may kill some germs (bacteria) in the gut that may have some role in IBS. It is taken for two weeks. Further research is needed to clarify its role in IBS.
- A medicine called tegaserod seems to be useful for people with constipation.
- Studies have shown that certain Chinese herbal medicines may help to ease symptoms in some cases. However, results vary. So more research is needed to clarify their safety and usefulness.
- Newer medicines that affect certain functions of the gut are also being developed and may become useful treatments in the future.
|FOODMAP||High FODMAP foods||Low FODMAP foods|
|Oligosaccharides: fructans and/or galacto-oligosaccharides||Vegetables: artichokes, asparagus, beetroot, Brussels sprouts, broccoli, cabbage, fennel, garlic, leeks, shallots, okra, onions, peas||Vegetables: carrot, cucumber, potato, bell pepper, eggplant, green beans, lettuce, spinach, chives, parsnip, pumpkin, silverbeet, spring onion (green only), tomato, zucchini, bamboo shoots, bok choy, choko, choy sum|
|Cereals: wheat & rye when eaten in large amounts (e.g., bread, pasta, crackers)||Cereals: wheat-free grains or wheat-free flours and products made with these (e.g., bread, pasta, crackers), spelt and spelt products, oats, corn, rice, quinoa|
|Legumes: chickpeas, lentils, red kidney beans, baked beans||Legumes: canned chickpeas|
|Fruits: watermelon, custard apple, white peaches, rambutan, kaki|
|Disaccharides: Lactose||Milk (cow, goat, sheep), yoghurt, soft & fresh cheeses (e.g., Ricotta, Cottage), ice cream||Lactose-free milk, rice milk, almond milk, lactose-free yoghurt, hard cheeses (e.g., Cheddar, Parmesan, Swiss, Brie, Camembert), butter, ice-cream substitutes (e.g., dairy-free gelato, sorbet)|
|Monosaccharides: Fructose||Fruits: apples, pears, nashi pears, clingstone peaches, mango, sugar snap peas, watermelon, tinned fruit in natural juice, dried fruits||Fruits: banana, blueberry, grapefruit, grape, honeydew melon, kiwifruit, lemon, lime, mandarin, orange, tangelo, raspberry, strawberry, pawpaw, star fruit, passion fruit, rockmelon, carambola, durian|
|Honey||Honey substitutes: maple syrup|
|Sweeteners: fructose, high fructose corn syrup||Sweeteners: sugar, glucose, artificial sweeteners not ending in “-ol”|
|Polyols||Fruits: apples, apricots, cherries, longon, lychee, nashi pears, nectarines, pears, peaches, plums, prunes, watermelon||Fruits: banana, blueberry, grapefruit, grape, honeydew melon, kiwifruit, lemon, lime, mandarin, orange, raspberry, pawpaw, star fruit, passion fruit, rockmelon, carambola, durian|
|Vegetables: avocado, cauliflower, mushrooms, snow peas|
|Sweeteners: sorbitol, mannitol, xylitol & others ending in “-ol”, isomalt||Sweeteners: sugar, glucose, artificial sweeteners not ending in “-ol” (e.g., sucralose, aspartame)|
Emerging therapies for irritable bowel syndrome
|Agent||Mechanism of action||Targeted disorder||Clinical status|
|Peripheral acting agents|
|Crofelemer||CFTR inhibitor||IBS-D||Phase 2b complete|
|Linaclotide (MD-1100)||Guanylatecyclase-c agonist||IBS-C||Approved by US FDA in 2012, 30th August|
|Arverapamil (AGI-003)||Calcium channel blocker||IBS-D||Phase 3|
|Verapamil||Kappa opioid agonist||IBS||Phase 2b complete|
|Mitemcinal||Motilin receptor agonist||IBS-C||Phase 2|
|Peripheral and central acting agents|
|Ramosetron||5-HT 3 antagonist||IBS-D||Phase 3|
|TD-5108||5-HT 4 agonist||IBS-C||Phase 2|
|DDP-773||5-HT 3 agonist||IBS-C||Phase 2|
|BMS-562086||Corticotropin-releasing hormone antagonist||IBS-D||Phase 2|
|GW876008||(319) Corticotropin-releasing hormone antagonist||IBS||Phase 2|
|DDP-225||5-HT 3 antagonist and NE reuptake inhibition||IBS-D||Phase 2|
|GTP-010||Glucagon-like peptide||IBS pain||Phase 2|
|AGN-203818||Alpha receptor agonist||IBS pain||Phase 2|
|Solabegron||Beta-3 receptor agonist||IBS||Phase 2|
|Espindolol (AGI-011)||Beta receptor antagonist||IBS (all subtypes)||Phase 2|
|Dextofisopam||2,3 benzodiazepine receptors||IBS-D and IBS-M||Phase 3|
Other types of treatment
Psychological treatments (talking treatments)
Situations such as family problems, work stress, examinations, recurring thoughts of previous abuse, etc, may trigger symptoms of irritable bowel syndrome (IBS) in some people. People with anxious personalities may find symptoms difficult to control.
The relationship between the mind, brain, nervous impulses, and overactivity of internal organs such as the gut is complex. Psychological treatments are mainly considered in people with moderate-to-severe IBS:
- When other treatments have failed; or
- When it seems that stress or psychological factors are contributing to causing symptoms.
The National Institute of Health and Care Excellence (NICE) recommends that cognitive behavioural therapy (CBT), hypnotherapy or psychological therapy should be considered when your symptoms have not improved with medication after one year. However, some of these treatments may not be available on the NHS in your area, or there may be long waiting lists. There is also not so much evidence about how well they work as there is for some other treatment options.
Foods Should You Avoid If You Have Irritable Bowel Syndrome
Whether you have IBS-D or IBS-C, there are foods to avoid that may trigger symptoms.
Certain foods may worsen bloating and gassiness. Foods to avoid include cruciferous vegetables and legumes, such as:
- Brussels sprouts
- Bok choy
- Chinese cabbage
- Collard greens
Legumes also may worsen gassiness and bloating, for example:
- Black beans
- lack-eyed peas
- Chickpeas (garbanzo beans)
- Fava beans
- Lima beans
- Red kidney beans
- Soy nuts
Some foods may trigger symptoms of abdominal cramps and diarrhea, including:
- Fatty foods
- Fried foods
- Sorbitol (a sweetener found in many diet foods, candies, and gums)
- Fructose (found naturally in honey and some fruits, and also used as a sweetener)
Eating large meals may also trigger abdominal cramping and diarrhea.
What Other Lifestyle Changes Help Relieve Irritable Bowel Syndrome IBS
In addition to dietary changes, there are some healthy habits that may also help reduce IBS symptoms.
- Maintain good physical fitness to improve bowel function and help reduce stress.
- Exercise regularly.
- Stop smoking for overall good health.
- Avoid coffee/caffeine and chewing gum.
- Reducing or eliminating alcohol consumption may help.
- Stress management can help prevent or ease IBS symptoms.
- Use relaxation techniques: deep breathing, visualization, Yoga
- Do things you find enjoyable: talk to friends, read, listen to music
- Gut-directed hypnosis can reduce stress and anxiety
- Biofeedback teaches you to recognize your body’s responses to stress and you can learn to slow your heart rate and relax.
- Pain management techniques can improve tolerance to pain
- Cognitive behavioral therapy or psychotherapy with trained counselors