My friend has been taking a laxative for more than two years. I don't think this is healthy and have told him so. He feels that since the laxatives he's using are "natural," it's okay. Do you think this practice is safe?

M.

Constipation is one of the most common reasons people go to gastroenterologists. Often, people try taking over-the-counter medications, herbs or "home remedies" before consulting a doctor. Generally, these are very safe medications if taken responsibly and for short periods of time. Some of the alternative herbal and natural remedies contain the same safe compounds found in traditional over-the-counter drugs. However, some contain other active ingredients that may produce unpredictable side effects. So, people must exercise caution when taking such compounds.

There are many cases of patients who develop chronic constipation because of long-term, inappropriate use of certain laxatives. This condition, called "cathartic colon," is likely a result of long-term damage to the colon muscle because of the years of constant stimulation by laxatives. The laxatives that have been incriminated in the above condition include the anthranoid class (including the senna, aloe and cascara compounds), and the polyphenolic class (including phenolphthalein and bisacodyl). Both of these classes increase the propulsive function of the colon and cause more frequent bowel movements. While they are effective and widely available, such preparations should be used mainly for temporary bouts of constipation, and are not generally recommended for long-term use.

Other classes of laxatives have more favorable profiles for long-term use. These include the bulk type (fiber, psyllium), the unabsorbed sugars (lactulose, sorbitol), magnesium salts (milk of magnesia), and the detergent class (docusate sodium). All of these laxatives increase the amount of water in the stool, resulting in a softer stool that is easier to pass. Many people will not get relief from one type of laxative, but will do well with another. Thus, patients may need to try several laxatives before finding one that works for them.

Finally, it must be stressed that medications are not always necessary to treat constipation. A careful review of a patient's diet and lifestyle often reveals reasons for the constipation and ways to solve it. For example, some people may need to increase their fluid intake, while others may need to increase their fiber intake and/or reduce their fat intake. Still others may find that a cup or two of coffee helps to maintain their normal bowel movements. Other causes of constipation include certain prescription drugs, stressful events or frequent travel. In general, if someone develops constipation that lasts for more than a month, he or she should seek medical attention for further evaluation.