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Definition: Laxatives are products that promote bowel movements.
Purpose: Laxatives are used to treat constipation -- the passage of small amounts of hard, dry stools, usually fewer than three times a week. People who are constipated may find it difficult and even painful to have bowel movements. They may also feel bloated, sluggish, and generally uncomfortable and may have other symptoms such as a dull headache and low back pain. But these symptoms do not always mean that laxatives are necessary. A great deal of misunderstanding exists about their use. Many people believe that they are constipated and should take a laxative if they do not have a bowel movement every day or if their stools are sometimes hard. However, a wide range in normal bowel habits exists, depending on the individual and his or her diet. Some people have bowel movements as often as three times a day, some only three times a week. Anything within this range is considered normal. In addition, some people's stools are naturally firmer than others.
Occasional constipation can often be treated without laxatives. Increasing the amount of fiber in the diet, drinking enough water and other liquids, such as fruit and vegetable juices, exercising regularly, and setting aside time every day to have a bowel movement are the first steps. These measures will also help prevent constipation from occurring again. If these methods do not relieve the problem, a physician may suggest using a laxative for a limited time. A physician should always be the one to decide when a laxative is needed and which type of laxative should be used.
Description
Laxatives come in various forms -- liquids, tablets, suppositories, powders, granules, capsules, chewing gum, chocolate-flavored wafers, and caramels. The basic types of laxatives are bulk-forming laxatives, lubricant laxatives, stool softeners (also called emollient laxatives), and stimulant laxatives.
Bulk-forming laxatives
Bulk-forming laxatives contain materials, such as cellulose and psyllium, that pass through the digestive tract without being digested. In the intestines, these materials absorb liquid and swell, making the stool soft, bulky, and easier to pass. The bulky stool then stimulates the bowel to move. Laxatives in this group include such brands as FiberCon, Fiberall, and Metamucil.
Lubricant laxatives
Mineral oil is the mostly widely used lubricant laxative. Taken by mouth, the oil coats the stool. This keeps the stool moist and soft and makes it easier to pass. Lubricant laxatives are often used for patients who need to avoid straining -- after abdominal surgery, for example.
Stool softeners (emollient laxatives)
As their name suggests, stool softeners make stools softer and easier to pass by increasing their moisture content. This type of laxative does not really stimulate bowel movements, but it makes it possible to have bowel movements without straining. Stool softeners are best used to prevent constipation in people who need to avoid straining -- because of recent surgery, for example. However, they are not very effective at treating existing constipation. Docusate (Colace, Sof-Lax) is an example of a stool softener.
Stimulant laxatives
Ingredients in these laxatives stimulate muscles and nerves in the intestines. This helps move the stool along. Although these laxatives are popular and effective, they should be used with care, as they are more likely than other types to cause side effects. They may also work more quickly and powerfully than other laxatives. Examples of stimulant laxatives are bisacodyl (Correctol) and senna (Senokot).
Precautions
Laxatives are among the most widely misused over-the-counter medicines. The overuse of laxatives can lead the body to depend on them. When used regularly over a long time, laxatives can damage nerve cells in the colon, and the colon can lose its natural ability to contract. This makes constipation worse. Overuse of certain laxatives can weaken the bones and cause other serious problems. Because of these possible problems, do not use laxatives unless told to do so by a physician. If a physician has recommended a laxative, use it only as directed. Do not take it more often or for a longer period than recommended.
Occasional, temporary constipation usually results from an improper diet, too little exercise, changes in daily routines, or the use of certain medicines, such as pain relievers, antidepressant drugs, diuretics (water pills), and some antacids. However, constipation can also be caused by a number of diseases. See a physician for any of the following symptoms:
• Persistent constipation in a person who has always had regular bowel movements
• Constipation that does not get better with the proper use of laxatives
• Rectal bleeding or blood in the stool
• Pain when having a bowel movement
• Loss of appetite or unexplained weight loss
• Bloating that continues or gets worse
• Nausea
• Vomiting
• Continuing abdominal pain or cramps
• Sores or irritation in the anal area.
Do not use stool softeners, such as docusate (Colace) and lubricant laxatives, such as mineral oil, at the same time. This may cause unwanted side effects, such as watery diarrhea.
People whose gag reflexes do not work properly (such as people who have had strokes) should not use mineral oil laxatives. They may inhale small amounts of mineral oil, which could lead to inflammation of the lungs and possible pneumonia.
Some types of laxatives contain large amounts of sugar. People who have diabetes or who must limit their intake of sugar or other carbohydrates should read package labels carefully or check with a pharmacist before using laxatives.
People with phenylketonuria should be aware that sugar-free laxatives may contain aspartame.
When using a stimulant laxative, such as bisacodyl (Correctol), take the smallest recommended amount. Do not use this type of laxative on a daily basis.
Some stimulant laxatives can turn stools or urine pinkish or red. This is a harmless, temporary effect that should go away when the person stops taking the medicine.
Bulk-forming laxatives must be taken with at least 8 oz. of water or other liquid. If the laxative is taken without enough fluid, it may form a mass that can block the throat, esophagus, or bowel.
Anyone who develops a skin rash while taking a laxative should stop taking it immediately and call a physician.