Not to be confused with inflammatory bowel disease, irritable bowel syndrome is a chronic condition that affects the large intestine. IBS is characterized by a group of symptoms that occur at the same time, such as abdominal pain and cramping, bloating and changes in bowel movements.
IBS can affect anyone, but the condition is twice as likely to occur in women as in men, and most often begins in people younger than 45 years old.
Types of IBS
Irritable bowel syndrome can be classified, based on stool consistency, into one of four types. This classification helps health care providers accurately treat symptoms.
Irritable bowel syndrome with constipation is characterized by hard or lumpy stool at least 25 percent of the time and loose or watery stool less than 25 percent of the time.
Irritable bowel syndrome with diarrhea is characterized by loose or watery stool at least 25 percent of the time and hard or lumpy stool less than 25 percent of the time.
Mixed irritable bowel syndrome is characterized by hard or lumpy stool at least 25 percent of the time and loose or watery stool at least 25 percent of the time.
Unsubtyped irritable bowel syndrome is characterized by hard or lumpy stool less than 25 percent of the time and loose or watery stool less than 25 percent of the time. It’s also common for people to switch between types.
Causes of IBS
The causes of irritable bowel syndrome are unclear, and triggers vary between people. While there is no single cause of IBS, experts believe a combination of problems, such as stress, intestinal infections, bacterial overgrowth in the small intestine, sensitivity to pain, genetics and food sensitivities, may lead to the condition.
Symptoms of IBS
IBS doesn’t lead to other health problems or damage the GI tract, but it does have some uncomfortable symptoms. People with IBS often experience abdominal pain or discomfort, gas, bloating, constipation, diarrhea or both. Discomfort often starts shortly after eating and dissipates after making a bowel movement. Changes in frequency of movements are also common.
As with other chronic conditions, symptoms of irritable bowel syndrome persist for long periods of time – often years. If symptoms have occurred at least three times per month for the last three months, and symptoms began at least six month ago, you may have IBS.
Diagnosis of IBS
There is no single test for diagnosing IBS; your healthcare provider will likely assess your symptoms to diagnose the condition. Your provider will review your medical history and symptoms, and administer a physical exam.
Your provider may also order tests to rule out other conditions. A blood test may be performed to check for celiac disease; a stool culture test for infection; and a colonoscopy to check for cancer, especially if a patient is over age 50, experiences sudden and unexplained weight loss, bloody stool or has an abnormal blood test.
Treatments for IBS
The goal in treating IBS is eliminating the symptoms, but treatments aren’t one-size-fits-all, and individuals may need to manage symptoms with a combination of methods. Often, lifestyle changes to reduce stress, such as exercise and getting more sleep, can help manage symptoms. Dietary changes may also be helpful. Fiber-rich diets can help alleviate diarrhea and constipation, but may increase bloating. Your provider may also recommend avoiding foods that stimulate the intestines, like caffeine and alcohol, eating small meals and taking fiber supplements or laxatives.
If lifestyle changes don’t reduce symptoms, your health care provider may prescribe medications to manage symptoms.
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