Irritable bowel syndrome (IBS) is one of the most common gastrointestinal diseases. It affects an estimated 10 to 25% of the US population and accounts for over 3.5 million physician visits per year. IBS is more common among women than men, often diagnosed during adolescence or the second decade of life. Recognizing the IBS warning signs and symptoms can help you seek medical advice and get proper treatment without delays.
IBS warning signs and symptoms
Cramping, abdominal pain, bloating, and changes in bowel movement, such as diarrhea and/or constipation, are IBS symptoms. If these symptoms occur together for three months or more, you may have IBS, a disease that causes flare-ups that come and go. These acute episodes are experienced during the day, rarely making a person wake up at night.
Abdominal pain and cramps in IBS are related to or improve after having a bowel movement. Some individuals experience mostly diarrhea (diarrhea-predominant IBS or IBS-D), some have constipation-predominant IBS (IBS-C), while others have both diarrhea and constipation, or mixed IBS (IBS-M). Women are more likely to experience IBS-C and have more abdominal pain, while men are more likely to have IBS-D.
The stool consistency may vary, from very loose to lumpy or hard, and may contain mucus. A person with IBS often has the sensation of incomplete emptying after a bowel movement. Other symptoms may include nausea, headaches, low energy, depressed mood, muscle aches and pains, and brain fog. It is hard to predict how IBS may progress over time. Symptoms may aggravate or improve in severity over the years.
IBS causes and triggers
Unfortunately, the cause of IBS hasn’t been determined yet. While research on the causes of IBS is ongoing, researchers have identified several factors that play a role in causing it.
- Muscle contractions in the gut: IBS is associated with abnormal muscle contractions in the large intestine. In individuals with IBS-D, these contractions last longer and are stronger than normal ones, leading to diarrhea, excess gas, and bloating. With IBS-C, the contractions are weaker, causing slow intestinal transit and hard stools.
- Nerve impairments: IBS affects the nerves of the digestive tract and the signals between the gut and brain. As a result, IBS causes abdominal discomfort, increased sensitivity to pain, and changes in bowel movement.
- Post-infectious IBS: Gut infections such as stomach flu or bacterial overgrowth in the small intestine may trigger IBS development.
- Altered gut flora: Changes in the gut microbiota known as gut dysbiosis are emerging as a key player in IBS. According to this theory, altered gut flora leads to activation of the immune system in the gut and low-grade inflammation. These changes are responsible for increased sensitivity to pain and other IBS symptoms.
- Early life stress: Excessive stress during childhood may increase the risk of IBS later on in life.
In addition, certain things can trigger an IBS flare-up, including:
- Stress: Stressful events and other psychological factors can trigger a flare-up, worsen symptoms, and influence the outcome of IBS.
- Foods: Many people experience an aggravation of symptoms after eating foods. The most common culprits are wheat, dairy products, lemons and other citrus fruits, beans, cabbage, coffee, artificial sweeteners, and carbonated beverages.
- Certain medications, such as antibiotics, antidepressants, and those made with sorbitol.
- Lack of exercise.
- Eating too quickly.
Flare-ups can also develop without an identified trigger.
IBS diagnosis is based on the Rome criteria, guidelines used to help researchers and practitioners, and includes abdominal discomfort or pain lasting at least one day per week for three months or more. In addition, at least two of the following must be present:
- Pain and discomfort are related to bowel movements (defecation).
- The frequency of bowel movements changes, often diarrhea and/or constipation.
- The stool consistency or appearance is changed and can be loose, lumpy, or dry.
The type of IBS someone can be diagnosed with is based on the primary symptoms and can be constipation-predominant IBS, diarrhea-predominant IBS, or mixed IBS. Doctors may order additional tests like blood tests, stool tests, ultrasound, X-rays, or colonoscopy to rule out other digestive conditions such as celiac disease, infections, lactose intolerance, or inflammatory bowel disease.
Managing IBS symptoms is essential to prevent complications like hemorrhoids, decreased quality of life, depression, and anxiety. Mild cases require lifestyle modifications, while doctors often recommend medication for moderate and severe cases of IBS.
- Mild symptoms are treated with diet and other lifestyle changes like regular exercise, improving sleep, and stress management.
- Diet improves gut flora and reduces inflammation in the digestive tract. Eliminating food triggers such as gluten, dairy, artificial sweeteners, and high-gas foods like broccoli, cauliflower, and beans can reduce symptoms. A low FODMAP diet can help improve IBS in those who are sensitive to specific carbohydrates like fructose, fructans, and lactose. FODMAP is sugar carbohydrates, standing for fermentable oligosaccharides, disaccharides, monosaccharides, and polyols. These are foods that the small intestine has a hard time absorbing, and doctors may recommend a low FODMAP diet short-term to see if it helps with symptoms. A dietician can customize a diet based on an individual's needs.
- Eating frequent, smaller meals, like 5 to 6 meals rather than 2 to 3 large meals, could be beneficial to managing IBS. Staying well-hydrated is also important.
- Fiber supplements and laxatives help manage constipation. Doctors may recommend muscle relaxants, antidepressants, and pain medication in moderate to severe cases of IBS.
- Probiotic-rich foods like fermented vegetables and kefir and probiotic supplements are great additions to an IBS treatment plan. Probiotics promote the growth of friendly bacteria and help alleviate IBS symptoms, especially bloating. Not all probiotic formulas are created equally, and not everyone will respond the same way to a product, so it’s important to do your research.
- Enteric-coated peppermint capsules can effectively relieve abdominal pain, discomfort, bloating, and heartburn. Like probiotics, they are available over the counter.
- Doctors may recommend drugs to treat IBS. Options for IBS-D include alosetron, eluxadoline, or rifaximin, and lubiprostone or linaclotide are available for IBS-C.
- Behavior modification techniques, such as cognitive-behavioral therapy and hypnotherapy, are often effective for managing the symptoms.
- Fecal microbiota transplantation (FMT) is a therapy under investigation, showing promising results.
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