Laxative 168526 225214255 2008-07-12T14:27:13Z 168.7.238.63 /* Vegetables and foods */ {{Cleanup|date=July 2007}} {{redirect|Purgation|the Trigger The Bloodshed album|Purgation (album)}} '''Laxatives''' (or '''purgatives''') are foods, compounds, or drugs taken to induce bowel movements or to loosen the stool, most often taken to treat [[constipation]]. Certain stimulant, lubricant, and saline laxatives are used to evacuate the [[Colon (anatomy)|colon]] for [[rectum|rectal]] and bowel examinations, and may be supplemented by [[enema]]s in that circumstance. Sufficiently high doses of laxatives will cause [[diarrhea]]. Laxatives only work to hasten the elimination of undigested remains of food in the [[large intestine]] and [[colon]].{{Fact|date=January 2008}} There are several types of laxatives, listed below. Some laxatives combine more than one type of active ingredient to produce a combination of the effects mentioned. Laxatives may be [[oral route|oral]] or in [[suppository]] form. Constipation with no known organic cause, i.e. no medical [[explanation]], exhibits [[gender]] differences in [[prevalence]]: females are more often affected than males.<ref name=chang>{{cite journal |author=Chang L, Toner B, Fukudo S, Guthrie E, Locke G, Norton N, Sperber A |title=Gender, age, society, culture, and the patient's perspective in the functional gastrointestinal disorders |journal=Gastroenterology |volume=130 |issue=5 |pages=1435–46 |year=2006 |pmid=16678557 |doi=10.1053/j.gastro.2005.09.071}}</ref> Not surprisingly, some advertisers promote their brands as being more feminine and thereby tailor their message to the market. The way laxatives function in males and females, however, does not exhibit significant differences. ==Vegetables and foods== Some vegetables and foods can be eaten to cure constipation and act as laxatives, although the effectiveness may vary. These include: *[[Almond]]s *[[Aloe Vera]] *[[Apple Juice]] *[[Banana]]s *[[Beet]]s *Chicken [[Broth]] *[[Chicory]] *[[Chocolate]] *[[Coconut]] *[[Coffee]] *[[Dandelion]] *[[Date]]s *Dried [[apricot]]s *[[Eclipse (mints)]] *[[Endive]] *[[Fig]]s *[[Flaxseed]] *[[Grape]]s *Hot [[Tea]] w/ Lemon *[[Liquorice]] *[[Mangos]] *[[Molasses]] *[[Olive]]s *[[Papaya]]s *[[Parsley]] *[[Peach]]es/[[Apricot]]s *[[Pear]]s *[[Persimmon]]s *[[Pineapple]] *[[Plum]]s *[[Prune]]s/Prune Juice *[[Rhubarb]] *[[Soybean]]s *Spicy Foods *[[Turnip]]s *[[Walnut]]s *[[Watercress]] ==Bulk-producing agents== *Site of Action: Small and large intestine *Onset of Action: 12 - 72 hours *Examples: [[psyllium]] husk ([[Metamucil]]), methylcellulose (Citrucel), [[polycarbophil]], [[dietary fiber]], [[Apple (fruit)|apple]]s Also known as bulking agents or roughage, these include [[dietary fiber]]. 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 [[Peristalsis|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. ==Stool softeners / Surfactants== *Site of Action: Small and large intestine *Onset of Action: 12 - 72 hours *Examples: [[docusate]] (Colace, Diocto) These cause water and fats to penetrate the stool, making it easier to move along. Many of these quickly produce a tolerance effect and so become ineffective with prolonged use. Their strength is between that of the bulk producers and the stimulants, and they can be used for patients with occasional [[constipation]] or those with anorectal conditions for whom passage of a firm stool is painful. ==Lubricants / Emollient== *Site of Action: Colon *Onset of Action: 6 - 8 hours 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 minerals. ==Hydrating agents (osmotics)==<!-- This section is linked from [[Glycerol]] --> These cause the intestines to hold more water within, softening the stool. There are two principal types, saline and hyperosmotic. ===Saline=== *Site of Action: Small and large intestine *Onset of Action: 0.5 - 6 hours * Examples: Dibasic [[sodium phosphate]], [[magnesium citrate]], [[magnesium hydroxide]] ([[Milk of magnesia]]), [[magnesium sulfate]] (which is [[Epsom salt]]) , monobasic sodium phosphate, [[sodium biphosphate]]. Saline laxatives attract and retain water in the intestinal lumen, increasing intraluminal pressure and thus softening the stool. They will 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. Sulfate salts are considered the most potent.{{Fact|date=September 2007}} ===Hyperosmotic agents=== *Site of Action: Colon *Onset of Action: 0.5 - 3 hours *Examples: [[Glycerin]] [[suppositories]], [[Sorbitol]], [[Lactulose]], and [[Polyethylene glycol]] (PEG). Lactulose works by the osmotic effect, which retains water in the colon, lowering the [[pH]] and increasing colonic peristalsis. Lactulose is also indicated in [[Hepatic encephalopathy|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, NuLytely, and others. ====Effectiveness==== For adults, a [[randomized controlled trial]] found [[polyethylene glycol|PEG]] [MiraLax or GlycoLax] 17 grams once per day better than [[tegaserod]] 6 mg twice per day.<ref name="pmid17573794">{{cite journal |author=Di Palma JA, Cleveland MV, McGowan J, Herrera JL |title=A randomized, multicenter comparison of polyethylene glycol laxative and tegaserod in treatment of patients with chronic constipation |journal=Am. J. Gastroenterol. |volume=102 |issue=9 |pages=1964–71 |year=2007 |pmid=17573794 |doi=10.1111/j.1572-0241.2007.01365.x}}</ref> A [[randomized controlled trial]] found greater improvement from 2 sachets (26 grams) of [[polyethylene glycol|PEG]] versus or 2 sachets (20 grams) of [[lactulose]] <ref name=pmid9895382>{{cite journal | author = Attar A, Lémann M, Ferguson A, Halphen M, Boutron M, Flourié B, Alix E, Salmeron M, Guillemot F, Chaussade S, Ménard A, Moreau J, Naudin G, Barthet M | title = Comparison of a low dose polyethylene glycol electrolyte solution with lactulose for treatment of chronic constipation. | journal = Gut | volume = 44 | issue = 2 | pages = 226–30 | year = 1999 | pmid = 9895382}}</ref>. 17 grams/day of [[polyethylene glycol|PEG]] has been effective and safe in a [[randomized controlled trial]] for six months.<ref name="pmid17403074">{{cite journal |author=Dipalma JA, Cleveland MV, McGowan J, Herrera JL |title=A randomized, multicenter, placebo-controlled trial of polyethylene glycol laxative for chronic treatment of chronic constipation |journal=Am. J. Gastroenterol. |volume=102 |issue=7 |pages=1436–41 |year=2007 |pmid=17403074 |doi=10.1111/j.1572-0241.2007.01199.x}}</ref> Another [[randomized controlled trial]] found no difference between [[sorbitol]] and [[lactulose]] <ref name=pmid2122724>{{cite journal | author = Lederle F, Busch D, Mattox K, West M, Aske D | title = Cost-effective treatment of constipation in the elderly: a randomized double-blind comparison of sorbitol and lactulose. | journal = Am J Med | volume = 89 | issue = 5 | pages = 597–601 | year = 1990 | pmid = 2122724 | doi = 10.1016/0002-9343(90)90177-F}}</ref>. For children, [[Polyethylene glycol|PEG]] was found to be more effective than [[lactulose]].<ref>{{cite web |url=http://www.bestbets.org/cgi-bin/bets.pl?record=00901 |title=BestBETs: Is polyethylene glycol safe and effective for chro... |accessdate=2007-09-06 |format= |work=}}</ref> ==Stimulant / Irritant== *Site of Action : Colon <center> {|- border="1" cellpadding="3" cellspacing="0" align="center" width="350" style="border-collapse: collapse; margin: 0 0 0 0.5em" |+ bgcolor="#ddeeff" |Examples | '''Onset of Action''' | '''Laxative Name''' |- | | 6 - 8 hours | | *[[buckthorn|Cascara]] *[[Phenolphthalein]] (Formerly in Ex-lax but phased out because of [[carcinogenicity]] concerns) |- | | 6 - 10 hours | | *[[Bisacodyl]] tablets (Dulcolax) *Casanthranol *[[senna (herb)|Senna]] (Ex-lax) *[[Aloin]], from [[Aloe Vera]] |- | | 2 - 6 hours | | *[[Castor oil]] |- | | 15 min - 1 hour | | *[[Bisacodyl]] [[suppository]] *Microlax |- |}</center> These stimulate [[Peristalsis|peristaltic action]] and can be dangerous under certain circumstances. Long term use can lead to 'cathartic colon'.<ref name=pmid9649012>{{cite journal | author = Joo J, Ehrenpreis E, Gonzalez L, Kaye M, Breno S, Wexner S, Zaitman D, Secrest K | title = Alterations in colonic anatomy induced by chronic stimulant laxatives: the cathartic colon revisited. | journal = J Clin Gastroenterol | volume = 26 | issue = 4 | pages = 283–6 | year = 1998 | pmid = 9649012 | doi = 10.1097/00004836-199806000-00014}}</ref> Stimulant laxatives act on the intestinal [[mucosa]], or nerve plexus; they also alter water and [[electrolyte]] secretion. They are the most severe among laxatives and should be used only in extreme conditions. [[Castor oil]] may be preferred when more complete evacuation is required. ===Castor oil=== *Site of Action : Small intestine [[Castor oil]] acts directly on intestinal mucosa or nerve plexus and alters water and electrolyte secretion. It is converted into ricinoleic acid (the active component) in the gut. ==Serotonin agonist== [[Tegaserod]] is a motility stimulant that works through activation of [[serotonin|5-HT<sub>4</sub>]] receptors of the [[enteric nervous system]] in the [[gastrointestinal tract]]. However caution must be taken due to potentially harmful cardiovascular side-effects. ==Uses== Bowel Prep. Chronic constipation. Chronic immobility. ==Problems with use== ===Laxative Abuse=== Laxative abuse is potentially serious since it can lead to [[intestinal paralysis]],{{Fact|date=February 2007}} [[Irritable Bowel Syndrome]] (IBS),{{Fact|date=February 2007}} [[pancreatitis]],{{Fact|date=February 2007}} [[renal failure]],<ref name-copeland>{{cite journal |author=Copeland P |title=Renal failure associated with laxative abuse |journal=Psychother Psychosom |volume=62 |issue=3-4 |pages=200–2 |year=1994 |pmid=7531354 |doi=10.1159/000098619}}</ref><ref name=wright>{{cite journal |author=Wright L, DuVal J |title=Renal injury associated with laxative abuse |journal=South Med J |volume=80 |issue=10 |pages=1304–6 |year=1987 |pmid=3660046 |doi=10.1097/00007611-198710000-00024}}</ref> and other problems. ===Laxative gut=== Physicians generally 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. The evidence for this was never too strong, and it was always unclear whether the elongated and poorly moving colon of a patient with chronic constipation was a result of or was just a cause for patients' use of stimulant laxatives. A common finding in patients who have used stimulant laxatives is a brown pigment deposited in the intestinal tissue, known as [[Melanosis coli]]. ===Eating disorders=== Laxatives are often used by people with an eating disorder. In many cases of [[bulimia nervosa]] the patient will abuse laxatives in an attempt to purge themselves of food in the intestines before it becomes digested. Frequently, patients with eating disorders had chronic digestive problems in childhood and found laxatives an effective treatment. The laxative use later may substitute of more appropriate treatment such as a better diet. Treatment of patients with eating disorders and gastrointestinal illnesses can be challenging. {{fact | date= May 2008}} ==References== <references/> ==See also== * [[ATC code A06]] ==External links== *[http://www.nlm.nih.gov/medlineplus/druginfo/uspdi/202319.html Oral laxatives] - [[MedlinePlus]]. *[http://www.nlm.nih.gov/medlineplus/ency/article/002586.htm Laxative overdose] - [[MedlinePlus]]. {{Major Drug Groups}} {{Laxatives}} [[Category:Gastroenterology]] [[Category:Laxatives| ]] [[ca:Laxant]] [[cs:Laxativum]] [[de:Abführmittel]] [[es:Laxante]] [[fr:Laxatif]] [[hr:Laksativi]] [[id:Laksatif]] [[nl:Laxeermiddel]] [[ja:瀉下薬]] [[no:Avføringsmiddel]] [[pl:Środki przeczyszczające]] [[pt:Laxante]] [[ru:Слабительное]] [[simple:Laxative]] [[sk:Preháňadlo]] [[fi:Laksatiivi]] [[sv:Laxermedel]] [[th:ยาระบาย]] [[zh:泻药]]