Irritable Bowel Syndrome
Irritable bowel syndrome affects millions of people worldwide, causing uncomfortable digestive symptoms that can disrupt daily life. While there is no cure, understanding the condition and learning to manage it effectively can help you live a full and normal life.
Table of contents
- What is Irritable Bowel Syndrome?
- Types of IBS
- How Common is IBS?
- Symptoms of IBS
- What Causes IBS?
- How IBS is Diagnosed
- Treatment and Management
- Living with IBS
- Long-term Outlook
What is Irritable Bowel Syndrome?
Irritable bowel syndrome (IBS) is a common condition that affects the stomach and intestines, also called the gastrointestinal tract (the digestive system)[1]. It is one of the most common disorders affecting the digestive system, with symptoms that include cramping, belly pain, bloating, gas, and diarrhea or constipation, or both[1].
IBS is an ongoing condition that needs long-term management[1]. It is sometimes referred to as spastic colon, spastic colitis, mucous colitis or nervous stomach, though these are outdated terms[7]. IBS should not be confused with Inflammatory Bowel Disease (commonly referred to as IBD) which is primarily made up of ulcerative colitis and Crohn’s disease[7].
An important fact about IBS is that it doesn’t cause changes in bowel tissue or increase your risk of colorectal cancer[1]. IBS doesn’t damage your digestive tract or raise your risk for colon cancer[2]. Instead, it’s a chronic (long-term) condition that most people can manage by changing their routines and what they eat, taking medications and receiving behavioral therapy[2].
Types of IBS
Researchers categorize IBS based on how your stools (poop) look on the days when you’re having symptom flare-ups[2]. Most people with IBS have normal bowel movements on some days and abnormal ones on others. The abnormal days define the kind of IBS you have[2].
The main types of IBS are:
- IBS with constipation (IBS-C): Most of your poop is hard and lumpy[2].
- IBS with diarrhea (IBS-D): Most of your poop is loose and watery[2].
- IBS with mixed bowel habits (IBS-M): You have both hard and lumpy bowel movements and loose and watery movements[2].
The differences between these types are important. Certain treatments only work for specific types of IBS[2].
How Common is IBS?
IBS is very common. Experts estimate that about 10% to 15% of adults in the United States have IBS[2]. However, only about 5% to 7% see a provider and receive a diagnosis[2]. It’s the most common disease that gastroenterologists (experts in gastrointestinal diseases) diagnose[2].
IBS affects over 15 percent of the population[7]. It happens nearly twice more often in women than men[7]. Twice as many women are diagnosed with IBS than men[8]. The most common age of diagnosis is between 20 and 40 years old[8].
Symptoms of IBS
Symptoms of IBS vary but are usually present for a long time[1]. Symptoms of IBS can appear frequently, or they may occur during flare-ups. In other words, you don’t always experience symptoms. Instead, symptoms may go away (and you’ll have normal bowel movements). At other times, symptoms return[2].
The most common symptoms include:
- Belly pain, cramping or bloating that is related to passing stool[1]
- Changes in appearance of stool[1]
- Changes in how often you are passing stool[1]
- Excess gas and bloating[2]
- Diarrhea, constipation or alternating between the two[2]
- Mucus in your poop (may look whitish)[2]
- Feeling like you’re unable to empty your bowels after pooping[2]
Other symptoms that are often related include sensation of incomplete evacuation and increased gas or mucus in the stool[1]. People with IBS may experience abdominal pain and changes in bowel habits, either diarrhea, constipation, or both at different times[7]. Symptoms may be mild or severe and vary from person to person. The symptoms may come and go and can change over time[7].
Abdominal pain is the most common symptom and often is described as a cramping sensation[14]. The absence of abdominal pain essentially excludes irritable bowel syndrome[14].
Important warning signs: Fever, anemia (low red blood cell levels), rectal bleeding and unexplained weight loss are not symptoms of IBS and must be promptly evaluated by your physician[7]. It is not normal to pass blood, have diarrhea waking you from sleep or have unintentional weight loss of more than 2kg (4 pounds) if you have IBS. If this does happen, it is important to consult your doctor[16].
What Causes IBS?
Researchers don’t know exactly what causes IBS, but they classify it as a neurogastrointestinal disorder (a condition that affects how the gut and brain communicate)[2]. These conditions, also called disorders of the gut-brain interaction, have to do with problems with how your gut and brain coordinate to help your digestive system work[2].
While there is no definite cause of this syndrome, the symptoms of IBS seem to occur as a result of abnormal functioning or communication between the nervous system and the muscles of the bowel[7]. This abnormal regulation may cause the bowel to be “irritated” or more sensitive[7].
Communication challenges between your brain and gut can cause:
- Dysmotility: You may have problems with how your gastrointestinal muscles contract and move food through your gastrointestinal tract. The colon (large intestine) muscle tends to contract more in people with IBS. These contractions cause cramps and pain[2].
- Visceral hypersensitivity: You may have extra-sensitive nerves in your gastrointestinal tract. People with IBS tend to have a lower pain tolerance than people without it. Your digestive tract may be super sensitive to abdominal pain or discomfort[2].
Other potential causes of IBS include:
- Gut bacteria: Research has shown that people with IBS may have altered bacteria in their gastrointestinal tract, contributing to symptoms. Studies have shown that the types and amounts of gut bacteria are different in people with IBS than in people without it[2].
- Severe infections: Some people get diagnosed with IBS after an intestinal infection—known as post-infectious IBS[7].
- Genetic factors: There is a tendency for IBS to run in families, but no gene for IBS has been found[8].
Environmental factors, bacterial fermentation in the gut, bacterial overgrowth, food intolerance, altered bowel motility, intestinal hypersensitivity, altered nervous system processing, and alterations in hormonal regulation have all been considered as possible causes of IBS[7].
The role of stress: IBS is not caused by stress. It is not a psychological or psychiatric disorder; however, emotional stress may contribute to IBS symptoms[7]. Many people may experience increased symptoms of IBS when nervous or anxious[7]. There is an association between IBS and psychological disorders (e.g., anxiety, depression, posttraumatic stress disorder), with up to two-thirds of patients with IBS in tertiary care centers having a concurrent psychological disorder[14].
How IBS is Diagnosed
There’s no test to definitively diagnose IBS[9]. A healthcare professional is likely to start with a complete medical history, physical exam and tests to rule out other conditions, such as celiac disease and inflammatory bowel disease[9].
No test can confirm the diagnosis of IBS. Instead, it is often considered a “diagnosis of exclusion”, meaning other diseases must be ruled out before calling the problem IBS in a given patient[7]. However, there are specific features that are needed to make the diagnosis of IBS[7].
After other conditions have been ruled out, a care professional is likely to use one of these sets of diagnostic criteria for IBS:
- Rome criteria: These criteria include belly pain and discomfort averaging at least one day a week in the last three months. This also usually occurs with at least two of the following: pain and discomfort related to defecation, a change in the frequency of defecation, or a change in stool consistency[9].
Doctors use guidelines to help them to diagnose IBS. The pain happens for an average of one day per week or more for at least three months and is associated with a change in bowel habit[8].
The following blood tests might be used to rule out other problems:
- A check for anaemia. This is a low haemoglobin level in the blood, which can be caused by low iron levels. Anaemia is not a symptom of IBS. It could show other diseases[8].
- A check for how well the liver and kidneys are working[8].
- A check to see if there is inflammation in the gut. Doctors use a stool test called faecal calprotectin. If results are normal this can help show that the symptoms are not caused by Crohn’s disease or ulcerative colitis[8].
Tests may include blood tests, stool tests, flexible sigmoidoscopy or colonoscopy, and x-ray studies[7]. A healthcare professional may recommend several tests to help with diagnosis. Diagnostic procedures can include colonoscopy and CT scan[9].
Treatment and Management
The goals of treatment are symptom relief and improved quality of life[14]. Only a small number of people with IBS have severe symptoms. Some people can control their symptoms by managing diet, lifestyle and stress. More-severe symptoms can be treated with medicine and counseling[1].
Diet Changes
One of the most effective ways to manage IBS symptoms is through diet[1]. Changes in what you eat may help treat your symptoms[10]. Your doctor may recommend trying one of the following changes:
Common trigger foods include dairy, gluten, fatty foods, and certain fruits and vegetables[7]. FODMAP stands for Fermentable Oligosaccharides, Disaccharides, Monosaccharides, and Polyols. This diet focuses on lowering the intake of foods rich in specific fermentable sugars. These foods may include wheat, onions, and garlic[21].
General dietary recommendations include:
- Try to eat a healthy, balanced diet[12]
- Keep a diary of what you eat and any symptoms you get – try to avoid things that trigger your IBS[12]
- Try to drink at least 8 to 10 drinks of fluid (around 1.5 litres) a day, such as water or non-caffeinated drinks such as herbal tea[12]
- Do not delay or skip meals[12]
- Do not eat too quickly[12]
- Do not eat lots of fatty, spicy or processed foods[12]
- Do not eat more than 3 portions of fresh fruit a day (a portion is 80g)[12]
- Do not drink more than 3 cups of tea, coffee or any other caffeinated drink a day[12]
- Do not drink lots of alcohol or fizzy drinks[12]
Lifestyle Changes
Research suggests that other lifestyle changes may help IBS symptoms, including:
- Increasing your physical activity[10]
- Reducing stressful life situations as much as possible[10]
- Getting enough sleep[10]
Try to find ways to relax[12]. Get plenty of exercise[12]. Regular physical activity releases endorphins, which can help manage stress levels[21]. Regular exercise helps by reducing bloating and improving how well your bowels function. It also helps reduce stress, which in turn keeps you from having as many IBS symptoms[19].
Medications
Your doctor may recommend medicine to relieve your IBS symptoms[10]. To treat IBS with diarrhea, your doctor may recommend loperamide, rifaximin, eluxadoline or alosetron[10]. To treat IBS with constipation, your doctor may recommend fiber supplements, laxatives, lubiprostone, linaclotide or plecanatide[10].
Other medicines may help treat pain in your abdomen, including antispasmodics, antidepressants (such as low doses of tricyclic antidepressants and selective serotonin reuptake inhibitors), and coated peppermint oil capsules[10].
Medicines that can help include Buscopan, peppermint oil, loperamide (Imodium) for diarrhoea, and laxatives like Fybogel for constipation[12].
Probiotics
Your doctor may also recommend probiotics[10]. Probiotics are live microorganisms, most often bacteria, that are similar to microorganisms you normally have in your digestive tract[10]. Try probiotics for a month – they may help any symptoms caused by gut bacteria changes[12].
Live/bio yoghurts and fermented milk drinks contain cultures (bacteria). These bacteria may help further digestion of food in the lower part of the gut. This may reduce symptoms of wind and bloating. You will need to take these every day for at least 4 weeks for them to work[16].
Mental Health Therapies
Your doctor may recommend mental health therapies to help improve your IBS symptoms[10]. Therapies used to treat IBS include cognitive behavioral therapy, which focuses on helping you change thought patterns[10]. Treatment with antidepressants and psychological therapies are also effective for improving symptoms compared with usual care[14].
Implementing stress-reducing techniques can make a big difference. Practices like mindfulness meditation can help reduce stress and improve your overall well-being. Therapy, such as cognitive behavioral therapy, can also be helpful[21].
Living with IBS
Living with IBS can be unpredictable. One day you might feel fine, and the next, you’re dealing with severe abdominal pain and bloating. This unpredictability can make planning and participating in daily activities difficult. Social events, work meetings, and travel can become sources of anxiety[19].
Patients often have symptoms that tend to be more diarrhea-predominant or constipation-predominant. Symptoms may be mild or severe and vary from person to person. The symptoms may come and go and can change over time[7].
Practical Tips for Daily Life
Here are helpful strategies to manage IBS in daily life:
Take Your Comfort with You: Packing necessary items and having them on hand will encourage you to step out boldly. Keeping a backpack full and ready in your vehicle, under your desk, or waiting by the door will allow spontaneous participation in life’s surprises. It might include a change of clothes, baby wipes, needed medications or remedies, healthy snacks, and drinking water[17].
Plan Around the Pitfalls: Plan ahead and know where restrooms will be available along your route and at your destination. If you are traveling, book or choose an aisle seat near the facilities[17].
Prioritize Your Goals: Schedule your most important commitments for those times of day you are most likely to feel your best. Have important meetings before lunch, avoid meetings centered around eating if possible, and have your safe snacks and comfort kit along for the ride. A break between appointments allows you to rest, refresh, or even change if necessary[17].
Have Strong Allies Beside You: Having a supportive friend, family member, or co-worker who understands your condition and your symptom management strategies is a huge help[17].
Keep a Food Journal: This will help to identify potential IBS instigators[22]. Keeping a food journal is a great tool to help you learn which foods trigger or relieve IBS symptoms[23].
Long-term Outlook
Although IBS can cause a great deal of discomfort, it does not harm the intestines[6]. IBS doesn’t cause tissue damage in your gastrointestinal tract or increase your risk of more serious conditions, like colon cancer[2].
One prospective study of 112 patients diagnosed with IBS in the 1960s with long-term follow-up concluded that the presence of IBS did not increase the risk of mortality or the risk of developing other gastrointestinal diseases, such as chronic pancreatitis, gastrointestinal cancers, small bowel obstruction, and gastric ulcers[14].
If those living with IBS get timely and effective treatment, they can go about their regular activities without worry. However, the disease does require long-term management[19]. Can those living with IBS lead a long and normal life? Absolutely[21].
Most people diagnosed with IBS can control their symptoms with diet, stress management, probiotics, and medicine[6]. It’s usually a lifelong condition but lifestyle changes and medicine can help[4]. While there is no cure for IBS, certain approaches can reduce your symptoms[19].
- Stomach
- Intestines
- Gastrointestinal tract
- Large intestine (colon)
Spastic colon, Spastic colitis, Mucous colitis, Nervous stomach
