Constipation in Adults

In people with constipation, certain symptoms and characteristics are cause for concern. They include

• Distended, swollen abdomen

• Vomiting

• Blood in stool

• Weight loss

• New/worsening severe constipation in older adults

People who have warning signs should see a doctor right away, unless the only warning signs are weight loss and/or new constipation in older adults. In such cases, a delay of a few days to a week is not harmful.

People who have constipation but no warning signs should call their doctor, who can help decide how quickly they need to be seen. Depending on the person's other symptoms and known disorders, doctors may wish to see the person within a few days or may simply recommend trying changes in diet and/or a mild laxative.

Doctors first ask questions about the person's symptoms and medical history. Doctors then do a physical examination. What they find during the history and physical examination often suggests a cause of the constipation and the tests that may need to be done (see table Some Causes and Features of Constipation ).

During the history, doctors ask about the following:

• Stool frequency, consistency, and the need to strain or use maneuvers (such as pushing on the area between the scrotum or vagina and the anus [perineum] during defecation)

• Feeling of incomplete evacuation

• Satisfaction after defecation, including how often and how long people have used laxatives or enemas

• Diet and physical activity level, particularly any change in these factors

• Prescription and nonprescription medication use (particularly those known to cause constipation such as opioids)

Doctors also ask about symptoms of metabolic disorders (such as hypothyroidism and diabetes ) and neurologic disorders (such as spinal cord injury ).

During the physical examination, doctors look at the following:

• Signs of bodywide (systemic) disease, including weight loss, fever, and severe wasting away of muscle and fat tissue (cachexia)

• The abdomen for distention and masses

• The rectum for fissures, hemorrhoids, blood, or masses (including fecal impaction) and also anal muscle tone and sensation

The need for tests depends on what doctors find during the history and physical examination, particularly whether warning signs are present. When the cause of the constipation is clear (such as medications, injury, or bed rest), doctors often treat the person’s symptoms and do no testing.

People with symptoms of intestinal obstruction undergo abdominal x-rays and possibly a computed tomography (CT) scan . Most people with no clear cause or whose symptoms have not been relieved with treatment should have tests. Typically, doctors do a colonoscopy (to detect cancer) and blood tests to check for an underactive thyroid gland (hypothyroidism ) or high calcium levels in the blood (hypercalcemia ).

People whose initial test results are normal but whose symptoms are not relieved with treatment usually require further testing. If the main symptom is difficulty with defecation, doctors measure the pressure inside the anus and rectum (called anorectal manometry). If the main symptom is infrequent defecation, doctors measure how long it takes stool to leave the intestines by having people swallow small, slightly radioactive objects that can be tracked using a scanner (a type of radionuclide scanning ) or swallow a wireless motility capsule that is tracked over several days.

People need to ingest enough fiber in their diet (typically 15 to 20 grams per day) to ensure adequate stool bulk. Vegetables, fruits, and bran are excellent sources of fiber. Many people find it convenient to sprinkle 2 or 3 teaspoons of unrefined miller’s bran on high-fiber cereal or fruit 2 or 3 times a day. To work well, fiber must be consumed with plenty of fluids.

People should try to make changes to their behavior. For example, people should try to move their bowels at the same time every day, preferably 15 to 45 minutes after breakfast, because eating food stimulates movement in the colon. Glycerin suppositories may also help people have regular, unhurried bowel movements.People should try to make changes to their behavior. For example, people should try to move their bowels at the same time every day, preferably 15 to 45 minutes after breakfast, because eating food stimulates movement in the colon. Glycerin suppositories may also help people have regular, unhurried bowel movements.

Doctors explain to people why diet and behavior modification are important in treating constipation. Doctors also explain that daily bowel movements are not necessary, that the bowel must be given a chance to function, and that frequent use of laxatives or enemas (more than once every 3 days) denies the bowel that chance. People who have obsessive-compulsive disorder (OCD) are treated for that disorder.

People who have dyssynergic defecation may need to see specialized therapists for biofeedback training.

Some laxatives are safe for long-term use. Other laxatives should be used only occasionally. Some laxatives are good for preventing constipation, others for treating it. There are several classes of laxatives, including the following (see also table Agents Used to Prevent or Treat Constipation ):

• Bulking agents

• Stool softeners

• Osmotic agents

• Stimulants

• Mu-opioid receptors

Bulking agents, such as bran and psyllium (also available in the fiber of many vegetables), add bulk to the stool and absorb water. The increased bulk stimulates the natural contractions of the intestine, and bulkier stools that contain more water are softer and easier to pass. Bulking agents act slowly and gently and are among the safest ways to promote regular bowel movements. These agents generally are taken in small amounts at first. The dose is increased gradually until regularity is achieved. People who use bulking agents should always drink plenty of fluids. These agents may cause problems with increased gas (flatulence) and bloating.such as bran and psyllium (also available in the fiber of many vegetables), add bulk to the stool and absorb water. The increased bulk stimulates the natural contractions of the intestine, and bulkier stools that contain more water are softer and easier to pass. Bulking agents act slowly and gently and are among the safest ways to promote regular bowel movements. These agents generally are taken in small amounts at first. The dose is increased gradually until regularity is achieved. People who use bulking agents should always drink plenty of fluids. These agents may cause problems with increased gas (flatulence) and bloating.

Stool softeners, such as docusate or mineral oil, act slowly to soften stools, making them easier to pass. In addition, the slightly increased bulk that results from these laxatives stimulates the natural contractions of the large intestine and thus promotes easier elimination. Some people, however, find the softened nature of the stool unpleasant. Stool softeners are best reserved for people who must avoid straining, such as people who have hemorrhoids or have recently had abdominal surgery.such as docusate or mineral oil, act slowly to soften stools, making them easier to pass. In addition, the slightly increased bulk that results from these laxatives stimulates the natural contractions of the large intestine and thus promotes easier elimination. Some people, however, find the softened nature of the stool unpleasant. Stool softeners are best reserved for people who must avoid straining, such as people who have hemorrhoids or have recently had abdominal surgery.

Osmotic agents pull large amounts of water into the large intestine, making the stool soft and loose. The excess fluid also stretches the walls of the large intestine, stimulating contractions. These laxatives consist of salts or sugars that are poorly absorbed. They may cause fluid retention in people who have kidney disease or heart failure, especially when given in large or frequent doses.

In general, osmotic agents are reasonably safe even when used regularly. However, osmotic agents that contain magnesium and phosphate are partially absorbed into the bloodstream and can be harmful to older adults, people who have kidney failure or kidney disease, and people who take medications that affect kidney function (such as diuretics, angiotensin-converting enzyme [ACE] inhibitors, and angiotensin II receptor blockers). Although a rare occurrence, some people have developed kidney failure from taking sodium phosphate laxatives by mouth to clear stool from the intestine before x-rays of the digestive tract are taken or before a colonoscopy is done.

Stimulant laxatives (such as phenolphthalein, bisacodyl, and anthraquinones) contain irritating substances, such as senna and cascara. These substances stimulate the walls of the large intestine, causing them to contract and move the stool. They are useful for preventing constipation in people who are taking medications that will almost certainly cause constipation, such as opioids. Stimulant laxatives are also often used to empty the large intestine before diagnostic tests are done.(such as phenolphthalein, bisacodyl, and anthraquinones) contain irritating substances, such as senna and cascara. These substances stimulate the walls of the large intestine, causing them to contract and move the stool. They are useful for preventing constipation in people who are taking medications that will almost certainly cause constipation, such as opioids. Stimulant laxatives are also often used to empty the large intestine before diagnostic tests are done.

Taken by mouth, stimulant laxatives usually cause a semisolid bowel movement in 6 to 8 hours, but they often cause cramping as well. As suppositories, stimulant laxatives often work in 15 to 60 minutes. Prolonged use of stimulant laxatives can create abnormal deposits of a dark pigment in the lining of the large intestine (a condition called melanosis coli). Other side effects include allergic reactions and loss of electrolytes from the blood. Also, the large intestine can become dependent on stimulant laxatives, leading to lazy bowel syndrome. Therefore, stimulant laxatives should be used only for brief periods.

Bisacodyl is an effective medication for chronic constipation. Anthraquinones are found in senna, cascara sagrada, aloe, and rhubarb and are common components of herbal and over-the-counter laxatives. Lubiprostone works by making the large intestine secrete extra fluid, which makes stool easier to pass. Unlike other stimulant laxatives, lubiprostone is safe for prolonged use. Bisacodyl is an effective medication for chronic constipation. Anthraquinones are found in senna, cascara sagrada, aloe, and rhubarb and are common components of herbal and over-the-counter laxatives. Lubiprostone works by making the large intestine secrete extra fluid, which makes stool easier to pass. Unlike other stimulant laxatives, lubiprostone is safe for prolonged use.

Mu-opioid receptor antagonists (such as methylnaltrexone, naloxegol, naldemedine, and alvimopan) are medications that are used to treat opioid-induced constipation that is not relieved by other measures. These medications are designed to block the effects of opioids on the bowel without interfering with the pain relief opioids deliver. The most common side effects include stomach pain, diarrhea, nausea, vomiting, and headache.(such as methylnaltrexone, naloxegol, naldemedine, and alvimopan) are medications that are used to treat opioid-induced constipation that is not relieved by other measures. These medications are designed to block the effects of opioids on the bowel without interfering with the pain relief opioids deliver. The most common side effects include stomach pain, diarrhea, nausea, vomiting, and headache.

Enemas mechanically flush stool from the rectum and lower part of the large intestine. Small-volume enemas can be purchased in squeeze bottles at a pharmacy. They can also be given with a reusable squeeze-ball device. However, small-volume enemas are often inadequate, especially for older adults, whose rectal capacity increases with age, thus making the rectum more easily stretched. Larger-volume enemas are given with an enema bag.

Plain water is often the best fluid to be used as an enema. The water should be room temperature to slightly warm, not hot or cold, and is gently directed into the rectum. (CAUTION: Too much force is dangerous.) People then expel the water, washing stool out with it.

Various ingredients are sometimes added to enemas. Prepackaged enemas often contain small amounts of salts, often phosphates. Other enemas contain small amounts of soap (soapsuds enema), which has a stimulant laxative effect, or mineral oil. These enemas offer little advantage, however, to plain water.Various ingredients are sometimes added to enemas. Prepackaged enemas often contain small amounts of salts, often phosphates. Other enemas contain small amounts of soap (soapsuds enema), which has a stimulant laxative effect, or mineral oil. These enemas offer little advantage, however, to plain water.

Very large-volume enemas, called colonic enemas, are rarely used in medical practice. Doctors use colonic enemas in people with very severe constipation (obstipation). Some practitioners of alternative medicine use colonic enemas in the belief that cleansing the large intestine is beneficial. Tea, coffee, and other substances are often added to colonic enemas but have no proven health value and may be dangerous.

Fecal impaction cannot be treated by modifying the diet or taking laxatives.

Fecal impaction is first treated with enemas of tap water followed by small enemas of commercially prepared solutions.

If these enemas do not work, the hard stool must be removed by a doctor or nurse using a gloved finger. This procedure is painful, so an anesthetic (such as lidocaine 5% ointment) is often applied. Some people need to be sedated.If these enemas do not work, the hard stool must be removed by a doctor or nurse using a gloved finger. This procedure is painful, so an anesthetic (such as lidocaine 5% ointment) is often applied. Some people need to be sedated.