Constipation: Diagnosis and Treatment

Diagnosis

• History and physical examination, including rectal exam, can establish the diagnosis.
  
• A detailed bowel diary, submitted by a patient or parent, may be helpful. Many people misjudge normal bowel function as abnormal.
  
• Blood testing is necessary if hypothyroidism, anorexia, hypercalcemia, or diabetes is suspected. These conditions may also apply in children, as may celiac disease, lead poisoning, cystic fibrosis, and urinary tract infection.
  
• X–ray of the abdomen can detect certain disorders and is also useful in monitoring hospitalized patients.
  
• Rarely, colonoscopy may be necessary to rule out obstruction or colon cancer.

Treatment

• The first step is to identify and treat a possible underlying cause, such as discontinuing or changing causative medications.
  
• Often, the most effective treatment is to increase fiber and fluid intake, and consume foods that reduce transit time of the stool through the intestine, such as fruit juices with sorbitol.
  
• Biofeedback and behavioral changes may be helpful in some cases, especially in children. Biofeedback is a psychological technique in which patients are trained to recognize and respond to signals from their own bodies.
  
• Severe constipation may require a multidimensional approach that includes manual disimpaction.
  
• Drug therapy may include:
  
• Bulk–forming agents (e.g., oral fiber supplements, such as psyllium)
  
• Hyperosmolar agents (e.g., lactulose, sorbitol, and glycerin)
  
• Emollients (e.g., docusate or mineral oil), which soften stools, but are less effective than other drugs.
  
• Stimulants (e.g., senna, bisacodyl, and castor oil), which increase movement of the intestines. These are not suitable for long–term use.
  
• Prokinetic agents (misoprostol, colchicine, and tegaserod)

Many of these drugs can be used in children, but doses must be adjusted accordingly. Enemas and stimulant laxatives should not be used in infants.

Laxatives are not generally recommended, because they prevent the bowel from recovering normal function and often need to be continued. Although they are generally well tolerated, laxatives may cause abdominal distention, nausea, anorexia, cramps, gas, and (rarely) malabsorption or dangerous chemical imbalances.

• Biofeedback training to exercise the anal musculature and sphincter may be useful in some patients, especially those with pelvic floor muscle dysfunction.
  
• Rarely, surgery may be an option for patients with severe symptoms.
  

Physical activity has been shown to be effective to improve symptoms. Individuals who report daily physical activity have roughly half the risk for constipation, compared with those who are least active. When higher levels of both activity and fiber intake are paired, the risk for constipation drops roughly 70 percent, compared with individuals who are least active and eat the least fiber.