What Is IBS?
Irritable bowel syndrome (IBS) — also known as irritable bowel disease (IBD), spastic colitis and nervous colon — is a chronic condition that affects the large intestine. It is characterized by abdominal pain, bloating, irregular bowel habits, and alternating diarrhea and constipation.
Though symptoms can be debilitating, IBS does not typically cause long-term consequences, such as colorectal cancer.
IBS is a group of gastrointestinal (GI) symptoms that occur together. Typically, these symptoms last for at least three days each month, for at least three months. These symptoms do not cause damage to the digestive tract.
IBS is considered a functional GI disorder. A functional GI disorder is related to the gut-brain interaction, meaning that there may be problems with how the brain and the gut interact. Because of these changes, the gut can become more sensitive and change how the musculature in the gut contracts. This can lead to constipation or diarrhea — or both.
There are three types of IBS:
- IBS with constipation (IBS-C): This type is characterized by stools that are hard and lumpy
- IBS with diarrhea (IBS-D): This type is characterized by stools that are loose or watery
- IBS with mixed bowel habits (IBS-M): This type is characterized by bowel habits that are a combination of both constipation and diarrhea
Symptoms of IBS
Symptoms of IBS vary depending on the type of IBS that is experienced. The most common symptoms associated with IBS include:
- Abdominal pain and bloating that is relieved or partially removed by passing a stool
- Excess gas
- Diarrhea or constipation — or alternating bouts of diarrhea and constipation
- Mucus in the stool
Symptoms of IBS can wax and wane over time. Symptoms can go away for a period, then return. Some people, unfortunately, have continuous symptoms.
Causes of IBS
The cause of IBS is not known. There are several possible factors that may play a part in the development of IBS:
- Abnormal contractions of the intestines. The muscles that line the intestines contract to push food through the digestive tract. When these contractions are too strong or last longer than normal, gas, bloating and diarrhea may develop. When these contractions are too weak, hard stools develop, causing diarrhea.
- The nervous system may play a part. If there are abnormalities with the nerves in the GI tract, increased discomfort may be experienced when the abdomen stretches from stool and gas. If the signals between the brain and the GI system are poorly coordinated, pain, constipation and diarrhea can develop.
- Inflammation of the intestines can lead to IBS.
- IBS may develop after a severe infection, such as gastroenteritis. In addition, IBS may be associated with bacterial overgrowth in the intestines.
- It is theorized that people with IBS may have differences in their microflora than people without IBS.
Research also indicates that those who have experienced an emotional trauma have a higher likelihood of developing IBS.
Hormonal changes can worsen IBS. This can be problematic for women, as symptoms can worsen during menstruation or pregnancy.
Treatment of IBS
There is no single treatment that will treat IBS — treatment is aimed at symptom improvement and management of symptoms. IBS is incurable but can be managed.
Dietary changes can prove helpful:
- Avoid sorbitol. Sorbitol is a sugar alcohol found in various foods such as gum, diet foods and sugar-free candy. Sorbitol is known to cause diarrhea.
- Eat oatmeal, which may reduce gas and bloating.
- Eat at consistent mealtimes and eat slowly.
- Avoid sugary beverages and limit alcohol.
- Limit caffeinated tea and coffee to 3 cups per day.
- Drink adequate water each day — for example, 8 cups per day.
- Eat high-fiber foods.
In addition, your health care provider may recommend that you eliminate certain foods from your diet. Foods that are known to cause gas, such as broccoli, cabbage and cauliflower, may all worsen symptoms.
Gluten may be problematic for those who are intolerant. A low FODMAP — fermentable oligo-, di-, and monosaccharides and polyols — diet may be helpful for individuals who are sensitive to certain carbohydrates.
Stress reduction techniques can also be helpful:
- Regular exercise
- Yoga and tai chi
- Therapy, such as cognitive behavioral therapy (CBT)
Medications may also be prescribed:
- Fiber supplements, such as psyllium (Metamucil)
- Laxatives, such as polyethylene glycol (Miralax), may be prescribed for those with IBS-C
- Anti-diarrheal medications, such as loperamide (Imodium), can reduce diarrhea. These are purchased over the counter. Bile acid binders can also reduce diarrhea; examples include cholestyramine (Prevalite), colestipol (Colestid) and colesevelam (Welchol).
- Anticholinergic medications, such as dicyclomine (Bentyl), improve bowel spasms. Though considered safe, they can cause constipation, dry mouth and blurry vision.
- Antidepressants can improve depression symptoms — especially helpful if depression is worsening GI symptoms. SSRI antidepressants include fluoxetine (Prozac, Sarafem) and paroxetine (Paxil). Tricyclic antidepressants may also reduce pain associated with IBS; examples include (Tofranil), desipramine (Norpramine) or nortriptyline (Pamelor).