Irritable Bowel Syndrome

IBS or irritable bowel syndrome, also called spastic colon, is a disorder that affects the large intestine or colon. Specifically, it causes constipation, diarrhea, abdominal fullness or bloating, and lower abdominal pain. This disease affects at least 20% of all Americans in some capacity, occurs more often in women than men, and can be seen at any age.

Symptoms
The symptoms from IBS usually begin in one’s 20s or 30s. Symptoms mimicking IBS beginning in a patient over 50 years old usually point to a different diagnosis.
Symptoms in most individuals are mild, and may cause a tiny annoyance. Some patients experience disabling symptoms, which severely affect one’s quality of life. Either way, IBS is not life threatening and it does not permanently injure the large intestine. This syndrome does not lead to death of the intestines, bleeding from the intestines, or cancer from the intestines. Most people with IBS can get their symptoms under control and will lead long, healthy, normal lives. Symptoms are often controlled with a simple change in diet, exercise, stress reduction, and occasionally a medical regimen.

What causes IBS?
In short, that is unknown. Many theories exist. Many researchers believe that patients with IBS have a colon that is more sensitive than usual. This over-sensitivity to normal colonic peristalsis (movement of the colon to push the stool towards the anus) causes spasms and pain in the large intestine the patient feels as abdominal bloating and abdominal pain. These spasms, which are strong muscular contractions, can cause unbearable symptoms resulting in missed work, inability to get out of bed, insomnia, and even depression.  Someone with IBS may have a colon that responds abnormally to certain foods or stress. This abnormal response may lead to rushing of fluid into the colon, causing diarrhea, or rushing of fluid out of the colon causing constipation.  It is known that increased stress can cause IBS symptoms to worsen. Many patients with IBS will describe a worsening of symptoms during periods of stress such as exam time for students or after the death of a loved one. The exact cause of this stress response in the colon has not been elicited. These are just theories and not all the details of the etiology of IBS have been discovered.

Many symptoms of IBS exist but the most common are as follows:

1) Crampy abdominal pain and bloating. This pain is usually described in the lower abdomen. Pain usually dissipates after a bowel movement, after the pressure in the colon is reduced. As the stool is released the stretch of the colon is decreased and the pain is relieved.

2) Stool changes. Some patients with IBS have diarrhea, while others have constipation. Others alternate between periods of constipation (infrequent production of hard lumpy stool) and diarrhea (production of too much liquid stool). Usually one stool type predominates, and patients are categorized as “constipation predominant” or “diarrhea predominant” IBS. It is important to differentiate whether a patient is constipation predominant or diarrhea predominant, because treatment can be different. Many patients also suffer from mucous stools with this syndrome. The passing of mucous around the stool is a hallmark of IBS.

3) Alarm symptoms
Alarm symptoms should prompt a physician to look for other causes of bloating, abdominal pain, constipation, or diarrhea other than IBS. Alarm symptoms include weight loss, fevers, blood or black stools per rectum, and symptom initiation in a patient over 50 years of age. If alarm symptoms exist, a patient should undergo extensive diagnostic testing to rule out a more serious disorder.

4) Chronic symptoms
Chronic abdominal pain, bloating, diarrhea, or constipation should prompt a person to visit a physician. A complete history, physical exam including rectal exam will be performed. 

Diagnostic testing
If no alarm symptoms exist, no diagnostic testing except blood work may be performed.  If the history or physical exam points to a possible alternate diagnoses, diagnostic testing will be done. This may include additional blood work to rule out anemia (low blood counts) or thyroid abnormalities and stool tests to rule out bowel infection. Radiological or XRAY tests may be performed.  Colonoscopy may be performed,  depending on symptoms present and severity of symptoms. No specific diagnostic test exists for IBS, but if pertinent testing is done and no other cause for the symptoms is discovered, IBS will be diagnosed and treatment options will be discussed.

Treatment options
Change in diet, increased exercise, and stress reduction. These are the hallmark treatments for patients with IBS and work in some capacity in 75% of all patients.

Diet and exercise
A diet consisting of plenty of fruits and vegetables will be prescribed. It is important to avoid foods that cause intestinal gas, therefore fatty foods should be avoided. One should drink 8-10 glasses of water per day and avoid alcohol and tobacco, which will cause increased intestinal gas and bloating. Also avoid soda or carbonated beverages; and avoid chewing gum, which canlead to increased intestinal gas formation. A good exercise regimen can also help relieve the symptoms of irritable bowel syndrome.

High fiber diet or fiber supplement
If constipation exists, a high fiber diet or fiber supplement will be added. Whole grain breads and cereals, fruits, and vegetables are good sources of fiber. Initiation of a fiber regimen may cause abdominal bloating, but the body will quickly get used to the fiber and these unpleasant feelings will pass. The fiber will increase the bulk of stool, thus increasing the frequency of bowel movements.

Control with medications
Stress needs to be controlled. Medications that control depression and anxiety may be prescribed. As the brain becomes less tense the colon tends to follow suit.
Medications to control diarrhea, anti-diarrheals like Imodium and Pepto or medications to control constipation, like fiber and laxatives, may be prescribed. These medications do not offer a cure, but they offer relief of symptoms.
Alosetron or Lotronex was removed from the market and now has been approved again for the treatment of diarrhea predominant IBS. It was removed from the market due to the risk of ischemic colon (Bowel death requiring major abdominal surgery). It has been re-approved but should be used only after other medications have failed in patients with diarrhea predominant IBS.

Amitiza has been approved for patients with IBS with constipation features.  This medication increases the flow of fluids and electrolytes in the colon thus allowing easier stool passage. It’s exact mechanism for reducing pain in IBS patients has not been fully understood.