Evaluation and treatment of constipation

What is the approach to the evaluation and treatment of constipation?

There are several principles in approaching the evaluation and treatment of constipation.The first principle is todifferentiate between acute (recent onset) and chronic constipation.Thus, with acute constipation that is worsening, itis necessary to assess for the cause early so as not to overlook aserious illness that should be treated urgently.The second principle is to start treatmentearly and use the treatments that have the least potential for harm. This willprevent constipation from worsening, and it also will prevent potential damage tothe colon that can be caused by the frequent use of stimulantlaxatives. The third principle is to know when it is time to evaluate the causeof chronic constipation. Evaluation for the cause of chronic constipation needsto be done if there is no response to the simple treatments.The goal of treatment in constipation should not be a bowel movement everyday, but a bowel movement every two to three days without difficulty (withoutstraining). Start with the simple things. Don't suppress urges to defecate.When the urge comes, find a toilet. With the assistance of your physician andpharmacist, determine if there are drugs that you are taking that could becontributing to the constipation. See if the drugs can be discontinued orchanged. Increase the fiber in your diet by consuming more fruits, vegetables,and whole grains. (There are other health benefits from this recommendation aswell.) It may be difficult to get enough fiber in the diet to effectively treat constipation, so don't hesitate to take fiber supplements if necessary (wheatbran, psyllium, etc.). Use increasing amounts of fiber and/or change the type offiber consumed until there is a satisfactory result. Don't expect fiber towork overnight. Allow weeks for adequate trials.What if constipation does not respond to these simple, safe measures? Theseefforts should not be discontinued but other measures should be added. If the constipation is infrequent, that is, every few weeks (as it can be when due tothe menstrual cycle), it probably doesn't matter what other measures are added-emollient,saline, or hyper-osmolar laxatives, enemas, and suppositories. Even stimulantlaxatives every four to six weeks are unlikely to damage the colon. Unfortunately,the tendency when using stimulant laxatives is to unconsciously increase thefrequency of their use. Before you know it, you're taking them every week, ormore often, and permanent damage might result.If constipation is a continuous rather than an intermittent problem, probably thesafest laxatives to take on a regular basis are the hyper-osmolar laxatives. Their use should be supervised by a physician. Aswith fiber, increasing doses of different hyper-osmolar laxatives should be triedover several weeks until a satisfactory type and dose of laxative is found.Hyper-osmolar laxatives, however, can be expensive. Milk of magnesia is the mildestof the saline laxatives, is inexpensive, and provides a good alternative. Mostpatients can adjust the dose of milk of magnesia to soften the stool adequatelywithout developing diarrhea or leakage of stool.Prunes and prune juice have been used for many years to treat mild constipation. There is no evidence that the mild stimulant effects of prunes or prune juice damage the colon. Stronger stimulant laxatives usually are recommended only as a last resort after non-stimulant treatments have failed. Many people take herbs to treat their constipation because they feel more comfortable using a "natural" product.

A streatment of constipation prescription drug

Tegaserod was approved in 2002 by the FDA specifically for the treatment of constipation in women withirritable bowel syndrome. In March of 2007, the FDA asked Novartis, the company manufacturing tegaserod, to suspend sales of tegaserod in the U.S. because a retrospective analysis of data by Novartis from more than 18,000 patients showed a slight difference in the incidence of cardiovascular events (heart attacks, strokes and angina) among patients taking tegaserod compared to placebo. The data showed that cardiovascular events occurred in 13 out of 11,614 patients treated with tegaserod (.11%), compared to one cardiovascular event in 7,031 (.01%) placebo-treated patients. However, it is unclear whether tegaserod actually causes heart attacks and strokes. Doctors and scientists will be scrutinizing the data to determine the long-term safety of tegaserod.The mechanism whereby tegaserod relieves constipation is interesting and is related to its effects on the intestinal serotonin, a chemical that controls contractions of intestinal muscles. The contractions of the intestinal muscles control transit of digesting food through the intestine. More contractions speed transit, fewer contractions slow transit. In constipated patients, contractions are fewer. Serotonin is a chemical manufactured by nerves in the intestine that is released and then binds to muscle cells. Depending on which receptor it binds to on the muscle, serotonin can either promote or prevent contractions. The serotonin 5-HT4 receptor is a receptor that prevents contractions when serotonin binds to it. Tegaserod blocks the 5-HT4 receptor, prevents serotonin from binding to it, and thereby increases contractions of the intestinal muscles. The increased contractions speed the transit of digesting food and reduces constipation. In addition, tegaserod reduces the sensitivity of the intestinal pain-sensing nerves and can thereby reduce abdominal pain. In large placebo controlled trials involving men and women with chronic constipation, tegaserod was more effective than placebo in increasing the number of spontaneous bowel movements and reducing straining, abdominal bloating, abdominal pain, and abdominal discomfort. The most common side effect of tegaserod was diarrhea, which was usually mild or moderate and generally resolved within a few days while continuing treatment. Lubiprostone (Amitiza)Lubiprostone (Amitiza) is a selective chloride channel activator that increases secretion of chloride ions from the cells of the intestinal lining into the intestinal lumen. Sodium ions and water then follow the chloride ions into the lumen, and the water softens the stool. The FDA approved lubiprostone for the treatment of chronic constipation in both men and women in February 2006. At a dose of 24 micrograms twice a day, lubiprostone significantly and promptly increased bowel movements, improved stool consistency, and decreased straining. The most common side effect of initial clinical studies was mild to moderate nausea in 32% of patients treated with lubiprostone, compared to 3% of the controls. More long term studies of efficacy and side effects are needed to determine the place of lubiprostone in the treatment of constipation.Linaclotide (Linzess) Linaclotide (Linzess) is an oral drug that is not absorbed from the intestine. It stimulates the cells lining the small intestine to secrete fluid into the intestine. The increase in fluid secretion leads to an increased number of bowel movements. In addition, when constipation is associated with the abdominal pain of IBS, the pain also is reduced. Although the improvement in pain may be due to the improvement in constipation, linaclotide has been shown also to reduce the sensitivity of intestinal pain nerves, and this mechanism of action also may account for the decrease in pain.Linaclotide is moderately effective, and it's effectiveness depends on how a favorable response is defined. In the studies leading up to its approval, linaclotide was associated with a predefined response of an increase in bowel movements and a decrease in pain in approximately one-third (33%) of patients as compared with 17% of patients who received placebo. The response was better when pain and constipation were considered separately, with responses of approximately 50% for either.The only common side effect of linaclotide is diarrhea. It should not be used in children below the age of six because of serious toxicity (death) to very young mice in animal studies, and should be avoided in children ages six through 17.Miscellaneous drugsSeveral prescribed drugs that are used to treat medical diseases consistently cause (asa side effect) loose stools, even diarrhea. There actually areseveral small studies that have examined these drugs for the treatment ofconstipation.ColchicineColchicine is a drug that has been used for decades to treat gout. Mostpatients who take colchicine note a loosening of their stools. Colchicine hasalso been demonstrated to relieve constipation effectively in patients withoutgout.Misoprostol (Cytotec)Misoprostol (Cytotec) is a drug used primarily for preventing stomach ulcerscaused by nonsteroidal antiinflammatory drugs such as ibuprofen. Diarrhea isone of its consistent side-effects. Several studies have shown that misoprostolis effective in the short term treatment of constipation. Misoprostol isexpensive, and it is not clear if it will remain effective and safe with long-term use. Therefore, its role in the treatment of constipation remains to bedetermined.Orlistat (Xenical)Orlistat (Xenical) is a drug that is used primarily for reducing weight. It works by blocking the enzymes within the intestine thatdigest fat. The undigested fat is not absorbed, which accounts for the weight loss. Undigested fat is digested by bacteria within the intestine andthe products of this bacterial digestion promote the secretion of water. Theproducts of digestion also may affect the intestine in other ways, for example,by stimulating the intestinal muscles. In fact, in studies, orlistat hasbeen shown to be effective in treating constipation. Orlistat has fewimportant side effects, which is consistent with the fact that only very smallamounts of the drug are absorbed from the intestine.It is unclear if these prescribed drugs should be used for the treatment of constipation.Although it is difficult to recommend them specifically just for thetreatment of constipation, they might be considered for constipated individualswho are overweight, have gout, or need protection from non steroidalanti in flammatory drugs.