Constipation Predominant IBS

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Constipation-predominant irritable bowel syndrome (IBS-C) is a condition characterized by chronic constipation with associated abdominal pain. It is a subtype of irritable bowel syndrome (IBS), and approximately one-third of people who have IBS manifest the IBS-C type.

IBS-C is one if the functional gastrointestinal disorders (FGD), which are gastrointestinal (GI) disorders that produce signs and symptoms without an identifiable cause despite standard diagnostic testing. These disorders can cause significant distress. Lifestyle modifications and medication may reduce the symptoms.

Symptoms of IBS-C

The predominant symptoms of IBS-C are frequent constipation accompanied by pain when having a bowel movement.

Constipation

Constipation is defined based on the frequency of bowels movements, as well as the consistency of the stools. It is normal to have one or two bowels movements per day, but it is also normal to have less than one per day.

If you have fewer than three bowel movements in a week, that is considered constipation. And if your stool is hard, or if you have to strain during a bowel movement, that is also a component of constipation. Infrequent bowel movements and hard stools are symptoms that typically accompany each other.

Rome IV

The Rome IV criteria define FGD based on specific signs and symptoms. According to the Rome IV criteria, IBS-C is defined as a condition in which constipation and its associated pain must occur at least 3 days per month over the past three months, with at least 25 percent of stools described as hard, and less than 25 percent of stools described as soft.

Common Symptoms

In addition to the criteria for IBS-C, there are some other symptoms you may experience if you have constipation-predominant IBS.

Common symptoms of IBS-C include:

With IBS-C, loose stools are rarely experienced, unless using a laxative. Compared to the other IBS subtypes, people who have IBS-C are more likely to experience anxiety, depression and a lowered quality of life.

Risk Factors

There is no known cause of IBS-C. The symptoms occur because the digestive system does not function as it should, but there is no identifiable cause for this dysfunction. Dyssynergic defecation, which is dysfunction of the pelvic floor muscles, may play a role.

Older individuals and those who have a lower socioeconomic status are at higher risk for IBS-C. This could be due to dietary factors, changes in the function of the GI system with aging, or to a lack of physical activity.

Diagnosis of IBS-C

IBS-C is a diagnosis of exclusion, meaning that it is only diagnosed after other disorders that could cause your signs and symptoms have been ruled out.

If you are being evaluated for IBS-C, your doctor is likely to do a physical examination, run some blood work, and conduct a stool sample analysis. Other tests, including imaging tests and interventional tests such as colonoscopy, may be recommended depending on your symptoms and your medical history.

If your symptoms match the diagnostic criteria for IBS-C, and there is no evidence of any red-flag symptoms or other illness, IBS-C will be diagnosed.

IBS-C and Chronic Idiopathic Constipation (CIC)

IBS-C and chronic idiopathic constipation (also known as functional constipation) share many of the same symptoms. According to the Rome IV criteria for FGDs, the biggest difference is that IBS-C causes abdominal pain and discomfort alongside constipation, while idiopathic constipation is typically painless.

There has been a question among gastroenterologists that these are manifestations of the same disorder along a single disease spectrum, rather than two completely separate disorders. However, they two conditions tend to respond to different treatments, which suggests that they may be accurately considered two different conditions. At this point, the answer is not completely clear.

Treatment of IBS-C

Treatment for IBS-C includes dietary and lifestyle modifications, over-the-counter laxatives and prescription medications.

  • Diet and lifestyle: Your doctor may recommend that you slowly increase the amount of fiber in your diet to promote more regular bowel movements.
  • Laxatives: Over-the-counter laxatives such as Miralax or lactulose may help your constipation. Use only as directed and based on the advice of your doctor, as laxative overuse can cause serious side effects.
  • Amitiza (lubiprostone): A prescription medication that is FDA approved for treatment of IBS-C, lubiprostone increases fluid secretion in the intestines.
  • Medications used for IBS: Antidepressants may have an effect on the nerves of the GI system, and antispasmodics can relax the muscles of the GI system. These medications are not formally indicated for the treatment of IBS, but they are frequently prescribed to reduce the symptoms of IBS.
  • Behavioral interventions: Cognitive behavioral therapy may be recommended for treatment of IBS. If dyssynergic defecation is a contributing factor to your IBS-C symptoms, your doctor may recommend that you try biofeedback.
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