digestive disorders
Constipation in Adults
Treatment of Constipation
Any underlying disorder causing constipation must be treated. When possible, drugs that cause constipation are stopped or changed. Constipation is best prevented with a combination of exercise, a high-fiber diet, and an adequate intake of fluids. When a potentially constipating drug is prescribed and/or people are placed on bed rest, doctors often give a laxative and recommend increased intake of dietary fiber and fluids rather than waiting for constipation to develop. There are three approaches to treating people with constipation: Diet and behavior Laxatives Enemas Doctors are cautious with use of laxatives, suppositories, and enemas because they can cause diarrhea, dehydration, cramps, and/or dependence on laxatives. People with sudden abdominal pain of unknown cause, inflammatory bowel disorders, intestinal obstruction, gastrointestinal bleeding, or fecal impaction should not use laxatives or enemas. 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.Glycerinsuppositories 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 Treatment 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: Bulking agents Stool softeners Osmotic agents Stimulants Mu-opioid receptors Bulking agents,such as bran andpsyllium(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 asdocusateormineral oil, act slowly to soften stools, making them easier to pass. In addition, the slightly increased bulk that results from these drugs 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 agentspull 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 laxatives 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 people, people who have kidney failure or kidney disease, and people who take drugs that affect kidney function (such as diuretics, angiotensin-converting enzyme [ACE] inhibitors, andangiotensin IIreceptor 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 assennaand 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 drugs 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. Bisacodylis an effective drug for chronic constipation. Anthraquinones are found insenna, cascara sagrada, aloe, and rhubarb and are common components of herbal and over-the-counter laxatives.Lubiprostoneworks by making the large intestine secrete extra fluid, which makes stool easier to pass. Unlike other stimulant laxatives,lubiprostoneis safe for prolonged use. Mu-opioid receptor antagonists(such asmethylnaltrexone,naloxegol,naldemedine, andalvimopan) are drugs that are used to treat opioid-induced constipation that is not relieved by other measures. These drugs 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 people, 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. About 5 to 10 fluid ounces (150 to 300 milliliters) 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, ormineral 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 aslidocaine5% ointment) is often applied. Some people need to be sedated. Typically, an enema is given after the hard stool is removed. 