
[Middle English, from Old French laxatif, from Medieval Latin laxātīvus, preventing constipation, from Late Latin, assuaging, from Latin laxātus, past participle of laxāre, to relax, from laxus, loose. See lax.]
For more information on laxative, visit Britannica.com.
Key Terms: Cathartic, Constipation, Diarrhea, Electrolyte levels, Encephalopathy, Peristalsis.
Definition
A laxative is a drug that promotes bowel movements.
Purpose
Laxatives are used to prevent or treat constipation. They are also used to prepare the bowel for an examination or surgical procedure.
Description
Laxatives work in different ways, by stimulating colon movement, adding bulk to the contents of the colon, or drawing fluid or fat into the intestine. Some laxatives work by combining these functions. Most primary care physicians recommend that patients try the bulk-producing laxatives first before taking saline or stimulant laxatives.
Bisacodyl
Bisacodyl is a non-prescription stimulant laxative. It reduces short-term constipation and is also used to prepare the colon or rectum for an examination or surgical procedure. The drug works by stimulating colon movement (peristalsis); constipation is usually relieved within 15 minutes to one hour after administration of a suppository form and in 6 to 12 hours after taking the drug orally.
Calcium Polycarbophil
Calcium polycarbophil is a non-prescription bulk-forming laxative that is used to reduce both constipation and diarrhea. It draws water to the intestine, enlarging the size of the colon and thereby stimulating movement. It reduces diarrhea by taking extra water away from the stool. This drug should relieve constipation in 12 to 24 hours and have maximum effect in three days. Colitis patients should see a reduction in diarrhea within one week.
Docusate Calcium/Docusate Sodium
Docusate, a non-prescription laxative, helps a patient avoid constipation by softening the stool. It works by increasing the penetration of fluids into the stool by emulsifying feces, water and fat. Docusate prevents constipation and softens bowel movements and fecal impactions. This laxative should relieve constipation within one to three days.
Lactulose
Lactulose, a prescription laxative, reduces constipation and lowers blood ammonia levels. It works by drawing fluid into the intestine, raising the amount of water in the stool, and preventing the colon from absorbing ammonia. It is used to help people who suffer from chronic constipation.
Psyllium
Psyllium is a non-prescription bulk-forming laxative that reduces both constipation and diarrhea. It mixes with water to form a gel-like mass that can be easily passed through the colon. Constipation is relieved in 12 to 24 hours and maximum relief is achieved after several days.
Senna/Senokot
Senna/senokot is a non-prescription laxative that reduces constipation by promoting colon movement. It is used to treat bouts of constipation and to prepare the colon for an examination or surgical procedure. This laxative reduces constipation in eight to 10 hours.
New and Investigational Treatments for Constipation
Some newer options for the treatment of chronic constipation are being developed by various groups of researchers. These include such alternative therapies as biofeedback; newer drugs like tegaserod (Zelnorm) and prucalopride, which stimulate peristalsis; a nerve growth factor known as neurotrophin-3; and electrical stimulation of the colon.
Recommended Dosage
Laxatives may be taken by mouth or rectally (suppository or enema).
Bisacodyl
Calcium Polycarbophil
Docusate
Lactulose
For Constipation:
For Encephalopathy:
Psyllium
Senna/Senokot
Precautions
The doctor should be informed of any prior allergic drug reaction, especially prior reactions to any laxatives. Pregnancy is also a concern. Animal studies have shown laxatives to have adverse effects on pregnancy, but no human studies regarding pregnancy are currently available. These drugs are only given in pregnancy after the risks to the fetus have been taken under consideration. Nursing mothers should use caution and consult their doctors before receiving these drugs.
Bisacodyl should not be administered to patients with rectal fissures, abdominal pain, nausea, vomiting, appendicitis, abdominal surgery, ulcerated hemorrhoids, acute hepatitis, fecal impaction, or blockage in the biliary tract. Calcium polycarbophil should not be given to anyone with a gastrointestinal blockage (obstruction).
Both psyllium and docusate calcium/docusate sodium should be avoided by patients with intestinal blockage, fecal impaction, or nausea and vomiting. Lactulose should be avoided by patients who are elderly, have diabetes mellitus, eat a low galactose diet, or whose general health is poor.
Senna/senokot is inadvisable for patients with congestive heart failure, gastrointestinal bleeding, intestinal blockage, abdominal pain, nausea and vomiting, appendicitis, or prior abdominal surgery.
The American College of Toxicology states that cathartics should not be used as a means of clearing poisons from the digestive tract of a poisoning victim. Although some physicians have administered these laxatives along with activated charcoal in order to reduce the body's absorption of the poison, this treatment is no longer recommended.
Side Effects
Laxatives may have side effects. Some, such as nausea and vomiting, are more common than others. Side effects related to specific laxatives are described in this section. With repeated use, people may become dependent on laxatives. All side effects should be reported to a doctor.
Bisacodyl
Common side effects:
Less common side effects:
Life-threatening:
Calcium Polycarbophil
Side effects may include:
Life-threatening:
Docusate Calcium/Docusate Sodium
Side effects include:
Lactulose
Common side effects include:
Psyllium
Common side effects include:
Less common side effects include:
Senna/Senokot
Common side effects include:
Less common side effects include:
Life-threatening:
Interactions
Laxatives may interact with other drugs. Sometimes, the laxative can interfere with proper absorption of another drug. A patient must notify their doctor or pharmacist if he or she is already taking any medications so that the proper laxative can be selected or prescribed. Specific drug interactions are:
Resources
Books
Beers, Mark H., MD, and Robert Berkow, MD, editors. "Diarrhea and Constipation." Section 3, Chapter 27 in The Merck Manual of Diagnosis and Therapy. Whitehouse Station, NJ: Merck Research Laboratories, 2004.
Karch, A. M. Lippincott's Nursing Drug Guide. Springhouse, PA: Lippincott Williams & Wilkins, 2003.
Periodicals
DiPalma, J. A. "Current Treatment Options for Chronic Constipation." Reviews in Gastroenterological Disorders 4, Supplement 2 (2004): S34–S42.
Newton, G. D., W. S. Pray, and N. G. Popovich. "New OTC Drugs and Devices 2003: A Selective Review." Journal of the American Pharmaceutical Association 44 (March-April 2004): 211–225.
"Position Paper: Cathartics." Journal of Toxicology: Clinical Toxicology 42 (March 2004): 243–253.
Schiller, L. R. "New and Emerging Treatment Options for Chronic Constipation." Reviews in Gastroenterological Disorders 4, Supplement 2 (2004): S43–S51.
Talley, N. J. "Management of Chronic Constipation." Reviews in Gastroenterological Disorders 4 (Winter 2004): 18–24.
Organizations
American Society of Health-System Pharmacists (ASHP). 7272 Wisconsin Avenue, Bethesda, MD 20814. (301) 657–3000.
National Digestive Diseases Information Clearinghouse. 2 Information Way, Bethesda, MD 20892-3570. nddic@aerie.com.
United States Food and Drug Administration (FDA). 5600 Fishers Lane, Rockville, MD 20857-0001. (888) INFO-FDA.
—Rhonda Cloos, R.N.; Rebecca J. Frey, Ph.D.
a substance that helps the expulsion of food residues from the body. If strongly laxative it is termed purgative or cathartic. Dietary fibre and cellulose function because they retain water and add bulk to the contents of the intestine; Epsom salts (magnesium sulphate) also retain water; castor oil and drugs such as aloes, senna, cascara, and phenolphthalein irritate the intestinal mucosa. Undigested carbohydrates such as lactulose and sugar alcohols are also laxatives.
A substance that increases the frequency of bowel movements. It may also be used to encourage the formation of a softer or bulkier stool. Common laxatives include castor oil, senna (and its derivatives), magnesium sulphate, and some bulking agents (e.g. bran and methyl cellulose). Some common laxatives, such as castor oil and senna, irritate the gut lining and can cause severe cramps. They are sometimes used by people trying to lose weight but they can result in dehydration and malabsorption of nutrients, leading to nutrient deficiencies. Most experts agree that taking such laxatives is a dangerous and ineffective way to lose weight.
| lauromacrogols, latanoprost, laronidase | |
| leflunomide, lenalidomide, lenograstim |
Definition
Laxatives are products that promote bowel movements.
Description
Laxatives may be grouped by mechanism of action.
Saline cathartics include dibasic sodium phosphate (Phospo-Soda), magnesium citrate, magnesium hydroxide (milk of magnesia), magnesium sulfate (Epsom salts), sodium biphosphate, and others. They act by attracting and holding water in the intestinal lumen, and may produce a watery stool. Magnesium sulfate is the most potent of the laxatives in this group.
Stimulant and irritant laxatives increase the peristaltic movement of the intestine. Examples include cascara and bisadocyl (Dulcolax). Castor oil works in a similar fashion.
Bulk producing laxatives increase the volume of the stool, and will both soften the stool and stimulate intestinal motility. Psyillium (Metamucil, Konsil) and methylcellulose (Citrucel) are examples of this type. The overall effect is similar to that of eating high-fiber foods, and this class of laxative is most suitable for regular use.
Docusate (Colace) is the only representative example of the stool softener class. It holds water within the fecal mass, providing a larger, softer stool. Docusate has no effect on acute constipation, since it must be present before the fecal mass forms to have any effect, but may be useful for prevention of constipation in patients with recurrent problems, or those who are about to take a constipating drug, such as narcotic analgesics.
Mineral oil is an emollient laxative. It acts by retarding intestinal absorption of fecal water, thereby softening the stool.
The hyperosmotic laxatives are glycerin and lactulose (Chronulac, Duphalac), both of which act by holding water within the intestine. Lactulose may also increase peristaltic action of the intestine.
General Use
Laxatives are used to treat constipation—the passage of small amounts of hard, dry stools, usually fewer than three times a week. Constipation may be caused by several conditions, some of which are potentially serious, and require medical attention:
Chronic constipation occurs in 1–4% of children between the ages of four and 10. If constipation continues, it should be treated by a physician.
A reasonable first step is to assure that there is enough fiber in the diet. This may be done by switching to a high fiber breakfast cereal. If this doesn't lead to improvement, then medical attention is necessary.
Precautions
Short term use of laxatives is generally safe except in appendicitis, fecal impaction, or intestinal obstruction. Lactulose is composed of two sugar molecules; galactose and fructose, and should not be administered to patients who require a low galactose diet.
Chronic use of laxatives may result in fluid and electrolyte imbalances, steatorrhea, osteomalacia, diarrhea, cathartic colon, and liver disease. Excessive intake of mineral oil may cause impaired absorption of oil soluble vitamins, particularly A and D. Excessive use of magnesium salts may cause hypermanesemia.
Side Effects
Excessive use of laxatives may result in dependency on these products. This may cause a condition known as cathartic colon.
Excessive use of laxatives that contain sodium or magnesium may result in dangerously high blood levels of these elements.
Interactions
Mineral oil and docusate should not be used in combination. Docusate is an emulsifying agent which will increase the absorption of mineral oil.
Bisacodyl tablets are enteric coated, and so should not be used in combination with antacids. The antacids will cause premature rupture of the enteric coating.
Preventing Side Effects
Used properly, laxatives are very safe. Do not overuse or give in doses larger than those labeled. If constipation persists, obtain medical help.
Parental Concerns
Laxatives should not be used too frequently. Bulk laxatives such as psyllium should be the normal first choice.
Mineral oil should not be given to infants or other children while laying down. This may result in the oil going into the lungs.
Resources
Books
Beers, Mark H. and Robert Berkow, eds. The Merck Manual of Diagnosis and Therapy, 17th ed. Whitehouse Station, NJ: Merck and Company, Inc., 1999.
McAvoy, G., Miller J., Litvak K. AHFS Drug Information 2004. Amer. Soc Healthsys. Pharm, Bethesda 2004.
Siberry G.K., Iannone R. The Harriet Lane Handbook 15th ed. Mosby Publishing, Philadelphia, 2000.
Periodicals
Bell, EA, Wall, GC. "Pediatric constipation therapy using guidelines and polyethylene glycol 3350." Ann Pharmacother. 2004 Apr;38(4):686-93.
"Constipation, Laxatives and Dietary Fiber." HealthTips (April 1993): 9.
Griffin, GC, Roberts, SD, Graham, G. "How to resolve stool retention in a child. Underwear soiling is not a behavior problem." Postgrad Med 1999 Jan;105(1):159-61, 165-6, 172-3.
"Overuse Hazardous: Laxatives Rarely Needed." (Includes related article on types of laxatives.) FDA Consumer (April 1991): 33.
Patel, H, Law, A, Gouin, S. "Predictive factors for short-term symptom persistence in children after emergency department evaluation for constipation." Arch Pediatr Adolesc Med. 2000 Dec;154(12):1204-8.
Organizations
American Academy of Family Physicians 11400 Tomahawk Creek Parkway Leawood, KS 66211-2672.
Web Sites
Constipation in Infants and Children: Evaluation and Treatment. American Academy of Pediatrics.
Section on Gastroenterology and Nutrition (SOGN). American Academy of Pediatrics.
[Article by: Samuel Uretsky, PharmD]
A medicine that loosens the bowel contents and encourages evacuation. A laxative with a mild or gentle effect on the bowels is also known as an aperient; one with a strong effect is referred to as a cathartic or a purgative.

Laxatives (purgatives, aperients) are foods, compounds, or drugs taken to loosen the stool, most often taken to treat constipation. Certain stimulant, lubricant, and saline laxatives are used to evacuate the colon for rectal and/or bowel examinations, and may be supplemented by enemas under certain circumstances. Sufficiently high doses of laxatives may cause explosive diarrhea. Laxatives work to increase the movement of feces along the colon.[1]
Some laxatives combine more than one active ingredient. Laxatives may be oral or in suppository form.
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Some foods can be eaten to cure constipation and act as laxatives, although the effectiveness may vary. These include:
Also known as bulking agents or roughage, these include dietary fibre. Bulk-producing agents cause the stool to be bulkier and to retain more water, as well as forming an emollient gel, making it easier for peristaltic action to move it along. They should be taken with plenty of water. Bulk-producing agents have the gentlest of effects among laxatives and can be taken just for maintaining regular bowel movements.
These enable additional water and fats to be incorporated in the stool, making it easier to move.
These simply make the stool slippery, so that it slides through the intestine more easily. An example is mineral oil, which also retards colonic absorption of water, softening the stool. Mineral oil may decrease the absorption of fat-soluble vitamins and some minerals.
These cause the intestines to hold more water within, softening the stool. There are two principal types, saline and hyperosmotic.
Saline laxatives attract and retain water in the intestinal lumen, increasing intraluminal pressure and thus softening the stool. They also cause the release of cholecystokinin, which stimulates the digestion of fat and protein. Saline laxatives may alter a patient's fluid and electrolyte balance.
Lactulose works by the osmotic effect, which retains water in the colon, lowering the pH through bacterial fermentation to lactic, formic and acetic acid, and increasing colonic peristalsis. Lactulose is also indicated in Portal-systemic encephalopathy. Glycerin suppositories work mostly by hyperosmotic action, but also the sodium stearate in the preparation causes local irritation to the colon.
Solutions of polyethylene glycol and electrolytes (sodium chloride, sodium bicarbonate, potassium chloride, and sometimes sodium sulfate) are used for whole bowel irrigation, a process designed to prepare the bowel for surgery or colonoscopy and to treat certain types of poisoning. Brand names for these solutions include GoLytely, GlycoLax, CoLyte, Miralax, NuLytely, SUPREP, Fortrans and others.
For adults, a randomized controlled trial found PEG [MiraLax or GlycoLax] 17 grams once per day to be superior to tegaserod at 6 mg twice per day.[4] A randomized controlled trial found greater improvement from 2 sachets (26 grams) of PEG versus 2 sachets (20 grams) of lactulose.[5] 17 grams/day of PEG has been effective and safe in a randomized controlled trial for six months.[6] Another randomized controlled trial found no difference between sorbitol and lactulose.[7]
For children, PEG was found to be more effective than lactulose.[8]
Stimulant laxatives act on the intestinal mucosa or nerve plexus, altering water and electrolyte secretion. They also stimulate peristaltic action and can be dangerous under certain circumstances.[9] They are the most severe among laxatives and should be used with care.
| Preparation(s) | Type | Site of Action | Onset of |
|---|---|---|---|
| Cascara (casanthranol) | Anthraquinone | colon | 6–8 hours |
| Buckthorn | Anthraquinone | colon | 6–8 hours |
| Senna extract (senokot) | Anthraquinone | colon | 6–8 hours |
| Aloe vera (aloin) | Anthraquinone | colon | 8–10 hours |
| Phenolphthalein | Triphenylmethane | colon | 8 hours |
| Dulcolax (bisacodyl) (PO) | Triphenylmethane | colon | 6–12 hours |
| Dulcolax (bisacodyl) (suppository) | Triphenylmethane | colon | 60 minutes |
| Microlax | enema | rectum and colon | 15–60 minutes |
| Castor Oil | ricinoleic acid | small intestine | 2–6 hours |
Tegaserod is a motility stimulant that works through activation of 5-HT4 receptors of the enteric nervous system in the gastrointestinal tract. However caution must be taken due to potentially harmful cardiovascular side-effects.
Zelnorm (market name for Tegaserod) was discontinued from marketing in the United States on March 30, 2007[12] but is still available for prescription under tight controls.
Laxative abuse is potentially serious since it can lead to intestinal paralysis,[citation needed] irritable bowel syndrome (IBS),[13] pancreatitis,[citation needed] renal failure,[14][15] and other problems, even though recovery is possible with proper treatment.
Physicians warn against the chronic use of stimulant laxatives due to concern that chronic use causes the colonic tissues to get worn out over time and not be able to expel feces due to long term overstimulation. A common finding in patients who have used stimulant laxatives is a brown pigment deposited in the intestinal tissue, known as melanosis coli.
Laxatives are often used by people with an eating disorder. In cases of bulimia nervosa the patient abuses laxatives to get rid of calories, to purge food in the intestines before it becomes digested and absorbed by the body. This will not work, because laxatives hasten the elimination of undigested remains of food in the large intestine and colon. The large intestine and colon do not digest food. They just collect the undigested remains and hold it and absorb water until it is defaecated. Weight loss may be felt, but this is only temporary due to the fact that the person has expelled much of the fluids from their body. The common question of whether or not chronic diarrhea associated with laxative use can promote some degree of true weight loss remains unknown. In any case, this type of laxative misuse causes water to be lost more rapidly than is healthy, potentially leading to dehydration and electrolyte imbalance. Prolonged usage of laxatives will actually cause constipation. The sensation of bloating can be significant due to excessive water retention, leading to people with eating disorders to increase the dosage of the laxatives, resulting in dependency and further complicating the constipation.[original research?] Abusing stimulant-type laxatives can lead to permanent impairment of the bowels, and the constipation problem becomes irreversible. In addition, blood can develop in stools, and excessive blood loss can result in anemia. Patients recovering from laxative abuse often have several months of problematic water retention, resulting in temporary weight gain (not noticeable on the exterior), and sometimes "pitting" edema (in which pressing on the skin leaves an indentation).[citation needed]
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Dansk (Danish)
adj. - afførende
n. - afførende middel, laksativ
Nederlands (Dutch)
laxatief, laxerend, laxeermiddel
Français (French)
adj. - laxatif
n. - laxatif
Deutsch (German)
n. - Abführmittel
adj. - abführend
Ελληνική (Greek)
n. - καθαρτικό, υπακτικό, καθάρσιο
adj. - υπακτικός, καθαρτικός
Português (Portuguese)
n. - laxante (m)
adj. - laxativo
Русский (Russian)
слабительное средство, слабительный
Español (Spanish)
adj. - laxante, purgante
n. - laxante, purgante
Svenska (Swedish)
n. - laxermedel
adj. - (läk.) lösande, avförande, laxer-
中文(简体)(Chinese (Simplified))
通便的, 不简洁的, 泻药, 缓泻药
中文(繁體)(Chinese (Traditional))
adj. - 通便的, 不簡潔的
n. - 瀉藥, 緩瀉藥
한국어 (Korean)
adj. - 완화제의, 대변을 나오게 하는
n. - 완화제 , 하제
日本語 (Japanese)
n. - 下剤, 通じ薬
adj. - 通じを付ける
العربيه (Arabic)
(الاسم) مسهل, ملين, فالت, جامح بمعنى غير مكبوح للألسنه (صفه) مسهل, ملين
עברית (Hebrew)
adj. - גורם לשלשול
n. - (חומר) משלשל
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